Cognition, Vol. 2, No. 3

1

A note on the abstract

readings

DAVID McGill

of verbs of perception

CAPLAN Medical

School

Abstract A description is given of the linguistic contexts in which certain verbs of perception assume an abstract rather than a concrete meaning. The class of verbs which permit such a reading is defined. This class can be related to neuro-anatomical facts, which are themselves reIated to the human capacity for language. It is well known that certain verbs of perception can have either an abstract or a concrete meaning when followed by sentential complements. For instance, the verbs in the (a) versions of the following sentences have abstract meanings which might be rendered by the paraphrases ‘know’, ‘realize’ or ‘come to know’. This contrasts with the usual meaning of the verb, which is more concrete, relating to the particular sense to which the verb refers. The more concrete meanings are exemplified in the (b) versions of the sentences (l)-(3). (1)

(2) (3)

a. John felt that further American involvement in Vietnam would lead to catastrophe. b. John felt Mary trembling beneath her coat. a. John sees that the problem is very difficult. b. John saw the bus move down the street. a. John will hear by letter that his mother has been nominated. b. John will hear Van Cliburn’s playing of the concerto.

This paper attempts to describe the conditions under which verbs of perception can receive an abstract reading and to define the class of verbs for which this type of interpretation is possible. In (4), the set of complements and sequence of tenses for several verbs of perception is presented: Cognition

2(3),

269-277

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David Caplan

that Mary i

(4)

b.

John

is sick is shouting shouts will shout shouted

,

.

hears ’

/:;;earj[:;,j;;;;$

Examining the (a) versions of the sentences in (4), we can see that the verb in the principal clause has an abstract meaning when the subordinate verb is tensed. In the (a) version, we can interpret the main verb in a concrete way only when two conditions hold: The verb in the embedded sentence is in the progressive aspect, and the tense of the embedded verb is the same as that of the principal verb. That is, sentence (5) may have a concrete as well as an abstract meaning: (5)

John hears that Mary is sh0uting.l

It is possible that the second, concrete meaning of hears in (5) is due to ‘analogical’ processes which relate the interpretation of (5) to that of similar sentences which have either an embedded tenseless participle or an embedded gerund, (6): (6)

a. b.

John hears Mary shouting. John hears Mary’s shouting.

This approach to the ambiguity of (5) is made more plausible by the fact that the abstract meaning of hears is the preferred reading. Examining (4b), we may conclude that the concrete reading is assigned to a matrix verb of perception when the complement verb is tenseless (whether it be a participle, a gerund, or an infinitive without to). The insertion of most modal verbs into the principal clauses of sentences does not alter the interpretation of the verb as abstract or concrete. Consider the sentences in (7): hear that Mary

is sick is shouting cshouts will shout shouted

1. This is only possible, of course, when the embedded S creates an appropriate physical sensation; i.e., the complement S of the verb

.

hear must ‘make noise’ for the concrete interpretation to be possible.

A note on the abstract readings of verbs of perception

b.

John

might hear that Mary would I 1

271

‘is shouting’. is sick qshouts shouted will shout

The auxiliary may is permissible in these sentences in both of its senses, permission and possibility. In the (a) and (b) versions of the sentences in (7), the verb hear has an abstract sense. In the (c) version of the sentences, it has a concrete sense. This is in perfect accord with the principle of semantic determination we have suggested. The medals can (permission), must (obligation), could (permission), might, should (probability) and wozdd also behave regularly with resepct to the rules of interpretation. Consider, as examples, the following sentences: (8)

a.

b. c. d.

. is sick is singing sang i will sing I John could hear (was permitted to hear) that Mary would sing. hear that Mary is shouting. John might should (probability) { I John

can (is allowed to) hear that Mary i must (is obliged to) i

John would hear that Mary was shouting

if he took out his earplugs . secret 1), if her doctor didn’t keep it ({ Sentence (8a) has an abstract reading for the principal verb when the permission sense of can or the obligation sense of must is present. Sentence (8b) has an abstract meaning when the permission sense of could is present. Sentence (8~) is ambiguous with respect to the abstract or concrete interpretation of the principal verb, when should has the reading of probability. Sentence (8d) is ambiguous in the relevant respect. Both these ambiguities (8c, d) are predictable from the rules given above. The medals can and could (in the sense of ability) and must (in the sense of necessity; that is, in its meaning ‘it must be the case that . . . ‘) do affect the interpretation of the verbs we are discussing. Verbs of perception never have an abstract sense when one of these modals is present as the sole auxiliary in the principal clause.2 Consider the examples in (9): 2. When the modal can (ability) is present in the principal clause along with other auxiliary

verbs - for example, have - the main verb can have an abstract sense:

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The sentences in (9) cannot be interpreted to mean that John is able to understand or that it must be the case that he knows that Mary is in the state or is performing the action specified by the verb phrase of the subordinate sentence. It may be possible to interpret the sentences in (9) to mean that John deduces something about Mary from evidence presented to him via his sense of hearing. This is an interesting combination of the abstract and concrete meanings of the verb hear, which can only be used under special circumstances (such as, for instance, the situation in which John is a doctor, and Mary is breathing irregularly, in which we might say that John can hear that Mary is sick). It is closely connected to the normal concrete meaning of the verb. For instance, we cannot say: (10)

*John can hear by mail that Mary is sick

with the meaning: (11) John is able to learn by mail that Mary is sick. The concrete sense of the verb hear, on the other hand, can appear with the modals can and could (ability) and must (necessity). We have, for example: (12)

John

/zzf)/ can (is able to)

(necessit y

hear

Mary

sing

{Mary’!~~~~~}

Moreover, when the verb of the embedded sentential complement is in the progressive aspect, and the tenses of the embedded and principal verbs are the same, the principal verb has only a concrete interpretation: hear that Mary is singing.

The modal should (moral obligation - ‘ought to’) is also idiosyncratic. When it appears without other auxiliaries, the principal verb can have a concrete meaning only if the embedded verb is tenseless. In (14a) hear must be concrete, and in (14b) it must be abstract. There is no alternative concrete meaning in (14b).

John can hear that Mary is sick can mean John is able to have learned that Mary is sick. Similarly, for must, we have: John must have heard that the Albanians have invaded Greece

which can mean It must be the case that John has learned Greece.

that

the Albanians

have invaded

A note on the abstract readings of verbs of perception

(14)

273

a. John should (ought to) hear Mary’s singing. b. John should (ought to) hear that Mary is singing.3

The rule of semantic interpretation which covers sentences without modals - if the embedded verb is tensed, the matrix verb is abstract; if the embedded verb is tenseless, the matrix verb is concrete - is thus also applicable to most sentences with medals, though can and could (ability), must (necessity) and should (moral obligation) require some special statements. We now turn to the second question posed: What is the class of verbs of perception to which these rules apply? The verbs which admit both an abstract and a concrete interpretation include hear, feeI and see, but exclude look, watch, listen, touch, smell and taste. If we arrange these verbs with respect to the senses to which they refer and to their stativity or non-stativity, we have the following classification (verbs permitting an abstract reading are marked with *):

(15) SENSE :

VISION

HEARING

TOUCH

TASTE

SMELL

STATIVE

see*

hear*

feel*

taste

smell

NON-STATIVE

watch

listen to

feel, touch

taste

smell

I--- ADJ

look

sound

feel

taste

smell

Table (15) shows, first, that only stative verbs of perception permit an abstract as well as a concrete interpretation and, second, that verbs of taste and smell never have abstract meanings. We might try to relate these two statements by deriving the stative verbs taste and smell4 in some way from their non-stative homophonous counterparts and saying that verbs so derived do not permit abstract readings. However, this attempt at classification would fail, even if the stative verbs taste and smell could be related to their non-stative counterparts in a particular derivational way that did not also relate hear to listen to, because this approach would predict that the verb feel (stative) does not have an abstract meaning - which is false. It would appear that these two statements are separate: Only verbs which are both stative and refer to the senses of vision, hearing and touch permit an abstract reading. 3. Sentence (14b) John should (ought that Mary is singing can receive a interpretation if should is rendered to be able or will but with the meaning

to) hear

concrete as ought of should as moral obligation this reading is impossible. 4. The verb smell has a stative meaning in the sentence John smelled the gas as he came into the room in the sense in which John sensed

that gas was in the air as soon as he came into the room. In this sense, we cannot say either (*> Smell the gas as you come into the room or (*) What John did was to smell the gas as he came into the room. Of course, with a non-

stative meaning, both perfectly grammatical.

these

sentences

are

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David Caplan

Stativity has many syntactic consequences, and the fact that only stative verbs permit abstract interpretations must be listed as another distinguishing mark of these verbs. But is the separation of senses into vision, hearing and touch on the one hand and smell and taste on the other equally significant syntactically? In fact, there are other phenomena in English which indicate that there is a difference between verbs referring to the senses of vision, hearing and touch, and those referring to the senses of smell and taste. One syntactic phenomenon common only to verbs of vision, hearing and touch is that these verbs allow the deletion of a that complementizer. For example: (16)

John

(17)

John

saw that Mary would run to the store. heard i felt 1

saw Mary would run to the store. heard I felt i However, verbs referring to the senses of smell and taste do not allow deletion that complementizers (18) (19) (20) (21)

of

John smelled that the dinner was already cooked. John tasted that the pudding was already sweet. *?John smelled the dinner was already cooked. *?John tasted the pudding was already sweeL5

A second syntactic phenomenon which is common only to one of these two groups of verbs - in this case, to those verbs referring to the senses of taste and smell - is the ability of a verb to take complements of the form [__ of N], where the Noun in the of-phrase relates to the subject of the verb. We have, for instance, sentences like (22) and (23), but none of the form (24)-(26): (22)

After she finished preparing

(23)

John kissed Mary, and she tasted of cigarettes.

(24)

*John

(25)

*John

(26)

dinner,

Mary smelled of fish.

felt 1 Mary, and she felt of silk. 1touched j

watched Mary, and she saw of shoes. looked at { 1 *John listened to Mary, and she (sounded1 of giggles.6 \heard J

5. These facts were pointed out to me by Steve Anderson.

6. In Middle English, verbs like feel, hear, see, as well as smell and taste allowed partitive

A note on the abstract readings of verbs of perception

275

A third phenomenon which distinguishes these two classes of verbs is the ability of verbs of taste and smell to be used metaphorically when followed by an abstract noun : (27) (28)

John smelled danger in the air. John tasted defeat.

In this construction, these verbs take on almost an abstract meaning which, I suggest, is possible by analogy to the abstract reading of the verbs of vision, hearing and touch in other contexts. The metaphorical nature of (27) and (28) serves to highlight the usual inability of verbs of taste and smell to have an abstract meaning. Verbs of vision, hearing and touch do not have this type of metaphorical usage. (29) is a perfectly acceptable sentence but is not metaphorical as are (27) and (28). (29)

John saw danger all around.

These examples indicate that the division of verbs of perception into a group referring to the senses of smell and taste on the one hand, and a group referring to the senses of vision, touch and hearing on the other, is not unique to one syntactic or semantic phenomenon. It appears that this grouping plays a role in the grammar of English. Let us hazard a thought as to why this might be the case. The senses of vision, hearing and touch permit the construction of complex semiotic systems - systems which allow for reference to past and future events and in which abstracts notions are possible. Human language is, of course, one such system, and it is transmitted through the senses of hearing, touch and vision - by means of spoken and written language and braille - but not through the senses of taste and smell. Abstraction and tense being important properties of complex semiotic systems, it is probably not by chance that abstract readings are assigned to matrix verbs when embedded verbs are tensed, and that the verbs capable of assuming abstract readings are those referring to senses capable of transmitting information relating to abstraction and tense.’ We can take this analysis one step farther by asking why the senses of vision, touch and hearing are capable of transmitting human language while those of smell objects.

There were sentences

such as John

felt of cloth meaning John felt some cloth.

Modern English has only kept the [of Nl complements for the verbs smell and taste and the meaning of such phrases has changed from the partitive to the genetive sense. 7. This observation is rendered more persuasive by the fact that abstract readings are possible for verbs of exactly these senses in other Indo-European languages and at least some non-Indo-European languages (e.g.,

Chinese). Hebrew constitutes an exception, for in Hebrew the verb zo feel (emotionally) is not homonymous with the verb fo feel (tactilely). Notably, tactile transmission of language by braille is a recent development, and one might suppose that verbs of touch will occasionally be grouped with those of taste and smell on these grounds. Vision and audition would seem to form a group, as do olfaction and gustation, with touch falling in an intermediate position.

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David Caplan

and taste are not. One possible reason is that the number and range of percepts is greater in the former than in the latter senses. The import of this observation is weakened, however, by the fact that taste and smell apparently never subserve human language - even in communities where these senses are socially important and highly developed; verbs of these senses in languages in such cultures, such as Walbiri, have no abstract readings (Ken Hale, personal communication). Moreover, at least in relation to the senses of touch and hearing, very few elementary sensory units (the dots of braille and the distinctive features of phonology) seem to be needed to erect the structure of language. The essential attributes of language as a complex semiotic system would seem to be a function of the computation effected on the sensory elements, rather than a function of the number of sensory primes. A second line of investigation appears more fruitful. There are different neuroanatomical pathways underlying the senses of smell and taste on the one hand, and vision, touch and hearing on the other. The former have primary cortical projection areas (cortical areas which first receive incoming sensory data) in the limbic areas of the brain : Smell sensations pass initially to the molecular layer of the hippocampus; taste sensations pass via the nucleus of the tractus solitarius to the reticular formation and thalamus with major projections to limbic structures, as well as diffuse neo-cortical projections. The latter senses on the other hand have primary sensory projections areas in the neo-cortex: Vision in the occiptal lobe, hearing in the temporal lobe and touch in the parietal lobe. Now, the neo-cortex is phylogenetically the youngest part of the cerebrum and occupies a proportionally greater part of the total brain in man than in animals. It is generally agreed that the human neo-cortex is the site of most of the intellectual functions which are specifically human; in particular, it has been argued that the neurological basis of language resides in the pattern of cortico-cortical connections (subserving cross-modal associations) between the senses of touch, vision and hearing (Geschwind, 1965). Perhaps this pattern of primary projections and cortical connections explains (at least partly) the dependence of human language upon the senses of touch, vision and hearing, and this, in turn, relates to the abstract readings of verbs of these senses. What more might be concluded from these relationships between neural pathways, the ability of humans to form complex semiotic systems and a set of semantic regularities in English? Without considerable further study, I suggest that very little else follows. The pattern of localization of senses in man surely does not have predictable consequences in grammar, nor is it plausible to suggest that the pattern of abstract interpretations of verbs of perception is ‘located’ in some neural area (any more than it is reasonable to look at this stage of our knowledge for the brain areas subserving aspects of language such as the A-over-A principle, the transformational cycle, the conventions of conjunctive and disjunctive ordering of phonological rules, etc.). Nor

A note on the abstract readings of verbs of perception

217

would it be justified to introduce a feature such as [ flimbic] or [-f neo-cortical] into the grammar of English. The relationships cited are not in themselves explanations; rather, they require explanatory mechanisms of a psycho-linguistic and neuro-linguistic nature to be understood.

REFERENCES Geschwind, N. (1963, Dyscoonexion syndromes in animals and man. Brain 88,237-294

Dans cet article l’auteur dkrit les divers contextes linguistiques dans lesquels certains verbes de perception prennent une signification abstraite plutat que concrkte et definit les genres de verbes pour lesquels ce processus

s’avke vrai. Cette classification peut dtre consid&ecomme ayant un rapport avec des faits neuro-anatomiques qui eux-ml?mes sont lids avec les capacith linguistiques des &es humains.

2

Alterations

of the phonetic coding of speech sounds during repetition*

LOUIS M. GOLDSTEIN”” JAMES R. LACKNER”“” Brandeis University

Abstract One aspect of the comprehension of speech is the assignment of a phonetic representation to the sounds being heard. However, if a person Iistens to a meaningless syllable that is continually repeated, over time he will hear the syllable undergo a variety of changes. These changes are very systematic in character and represent alterations in the phonetic coding assigned to an unchanging sound stimulus. When the restricted nature of the changes that occur is analyzed phonetically, these changes are found to involve a reorganization of the phones constituting the syIlables and changes in a small number of distinctive features,

Introduction

When listening to someone speak, in addition to understanding from moment to moment what is being said, we also retain some information about the structure of the sound pattern that the speaker employed to convey his intent. For example, when sentence (1) is read quickly to a listener, (1) This guy, when the moon is full and bright, turns into the wolfman, he is likely to misinterpret the first two words of the sentence as ‘the sky’ when he first hears them. This interpretation is consistent with the context of the sentence * This research was supported in part by a Rosenstiel Biomedical Sciences grant, Brandeis University, and in part by NIMH Grant HD 05168-02. We wish to thank Victoria A. Fromkin for her helpful comments on an earlier draft of this paper.

** L.G. is now at the Department of Linguistics, University of California, Los Angeles. *** J.L. is also at the Department of Psychology, Massachusetts Institute of Technology. Reprint requests should be addressed to J. Lackner, Department of Psychology, Brandeis University, Waltham, Mass., 02154. Cognition 2( 3))

pp. 279-297

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until the end, when he hears ‘wolfman’, at which point he will have to change his interpretation of the first two words in order to arrive at a coherent meaning for the sentence. Since there is no single ambiguous lexical item in (l), whose alternative meanings will permit a coherent reading for the sentence, the listener must be able to substitute ‘the sky’ for ‘this guy’ on the basis of their sound patterns, a few seconds after the relevant sound stretch of the sentence was heard. Speech also can be phonetically coded in the absence of the higher-level linguistic representations that are important in the perception of sentences. Since a listener can repeat a string of (non-syntactically structured) nonsense syllables that he hears, he must be able to represent the acoustic input in a way that permits him to ‘translate’ it into a series of motor gestures. It is reasonable to assume, therefore, that people assign some representation to the sounds of speech and that this representation plays a role in speech perception. We will refer to this representation as the phonetic coding of speech and examine some evidence about how this coding is organized. Since speech is clearly a temporal process, it is possible to view the phonetic coding of speech as a sequence of units, each of which represents some perceived stretch of the sound heard. The syllable is the shortest stretch of speech that can be perceived or produced in isolation, and it is a logical candidate as minimal unit of the phonetic coding; stretches of speech larger than the syllable might be coded phonetically as a sequence of syllabic units. However, linguists have traditionally argued that syllables can be divided into smaller, abstract units along a time dimension (phones), on the basis of speakers’ intuitions about the ways in which syllables differ one from another and on the basis of the types of changes that are observed in the sound pattern of languages during the course of their histories. These abstract units are found to differ from each other in a limited number of dimensions that are referred to as distinctive features (see Chomsky and Halle, 1968; Ladefoged, 1971; for discussions of feature systems). Each phone in a language has a specified value on each of the various feature dimensions. Thus, the phonetic representation linguists assign to an utterance is a matrix in which the columns correspond to successive time segments (phones) and the rows correspond to the distinctive features. Although phones cannot always be isolated physically, abstract units of this size have traditionally been hypothesized to discover the phonetic regularities present in a language. Thus, there are at least two units which might serve as basic units of the phonetic coding - the phone (the successive segments of phonetic feature matrices) and the syllable. The experiment to be described investigates the possible role of such units in the phonetic coding of speech. Our experimental technique derives from some observations made by Warren and Gregory (1958) concerning the perceptual changes that occur when a person listens to a word that is repeated over and over. They found that after a few repetitions of

Alterations of the phonetic coding of speech sounds during repetition

281

a word listeners reported hearing different words. This phenomenon has been referred to as the verbal transformation effect. Although Warren (1968) states that many of the words reported are quite different, phonetically, from the stimulus word, some of the transforms reported by this subjects seem, in fact, to be phonetic resegmentations of the stimulus word (e.g., Warren and Warren, 1970, write that the sequence ‘tresstress-tress . . .’ is reported by some listeners as ‘stress-stress-stress . ..‘). If the verbal transformation effect does involve (among other possible processes) a reorganization into new groupings of the various units of the phonetic coding of the utterance being repeated, then different hypotheses about the nature of the units of the phonetic coding make different predictions about what types of transforms are likely to occur. Specifically, if there are units in the phonetic coding that correspond to the successive phones of distinctive feature matrices, then some systematic relationship among the distinctive feature matrices of the transforms reported for a particular speech stimulus may emerge, a systematic relationship that could not be expressed in terms of a reordering of entire syllabic units only. Previous work using the verbal transformation effect, however, has shown little phonetic systematicity. Warren (1968) has summarized studies that found ‘radical phonetic discrepancy’ between stimulus and transforms. Such studies may not be appropriate for investigating the phonetic coding of speech, however, since they employ meaningful words as stimuli, and usually find meaningful words reported as transforms, As Warren (1968) has observed, transforms reported by adult listeners tend to be meaningful words, and these words tend to be semantically related to each other. However, if non-meaningful words were used as stimuli and non-meaningful responses were examined separately from those that were meaningful, then it might be possible to discover purely phonetic constraints on how a subject reports hearing the stimulus. There is evidence that, in fact, phonetic constraints on transforms do exist. Warren (1961) found that when young adults reported nonsense words, these tended to be phonetic sequences which are possible in English. If an analysis of the non-meaningful transforms of non-meaningful stimuli revealed systematic phonetic constraints that could be expressed in terms of units the size of phones, and in terms of distinctive features, then this systematicity would constitute evidence that the phonetic coding is organized into units that correspond to these matrices. The experiment to be described below attempts such an analysis.

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Method

Stimuli [p”], [t”], [kh], [b], [d], [g]l Six vowels [tl, [&I,[=I, [aI, [ol, [Q1 an d six consonants were chosen for study. Stop consonants were selected to permit evaluation of possible differences between the types and number of transforms for consonants and vowels, as a function of the ear receiving the syllable. Both kinds of stimuli were included since it has been claimed that stop consonants are processed very differently from vowels (Liberman, Cooper, Shankweiler and Studdert-Kennedy, 1967), e.g., that there is a hemispheric lateralization in the processing of stop consonants but not vowels (Studdert-Kennedy and Shankweiler, 1970). Stop consonants were chosen that varied systematically along two phonetic dimensions; the features, voicing - [&voice] - and place of articulation - bilabial, alveolar, velar.2 For each of the three places of articulation, one voiced and one unvoiced consonant was selected. Vowels were chosen that varied along the feature [&back], denoting the position of the tongue in relation to the back of the mouth during articulation, and the feature of vowel height - the high, mid or low height of the tongue in the mouth during articulation. Vowel height is described by two features, [&high] and [flow]. One [-back] and one [fback] vowel were selected for each of the three vowel heights. The back vowels were all rounded, and the front vowels unrounded. All vowels were [-tense].3 Each consonant was presented in two different succeeding vowel environments. The vowels [E] and [t] were selected because few meaningful English words are formed by the resulting CVs generated. All six vowels were presented in two succeeding consonant environments; [kh] and [p”] were chosen because the resulting VCs do not form English words. Each vowel was also presented in isolation. The entire stimulus set included 30 syllables: 12 CV, 12 VC, and 6 V syllables.

1. Phonetic symbols used throughout are those of the International Phonetic Association. Those used as stimuli correspond to the consonants and vowels of English as follows: [tl-‘pit’; [&I-‘pet’; [el-‘pat’; [al-‘pot’; [o] does not occur in English, it is a shorter version of the vowel in ‘boat’; [ol-‘book’; [p”]-‘pat’; W-Yap’; [kh]-‘cap’; Lb]-‘bag’; [d]-‘dust’; [gl-‘gas’. 2. Place of articulation is described in the Chomsky and Halle (1968) feature system by two binary features - [&anterior] and

[ + coronal]; [ + anterior] segments are those produced with an obstruction in the vocal tract in front of the palato-alveolar ridge (where the ordinary English ‘sh’ is produced); [ +coronal] sounds are those produced with the blade of the tongue raised from its neutral position. 3. More recently, all low vowels have been considered phonetically [ + tense] (Perkell, 1971). On this view, the low vowels used in this experiment are [ + tense].

Alterations

Preparation

of stimulus

of the phonetic

coding of speech sounds during repetition

283

tapes

The syllables were recorded in a sound-insulated chamber, onto an Ampex AG500 tape recorder (at 15 ips). They were spoken so that the amplitude on the VU meter was approximately equivalent for all syllables.4 Seven copies of each syllable were then cross-recorded onto a Magnecord 1024. The point of onset for each copy of a syllable was determined by manually moving the tape over the playback head of the Ampex AG500. When the onset was found, defined as the ‘point’ at which the VU meter needle first showed a deflection, the tape was cut 1.5 inches (100 msec) prior to this point and 3 inches (200 msec) after it. The seven copies of each syllable were then spliced together into a continuous loop. The length (200 msec) of syllables and the interval between them (100 msec) was exactly the same for all stimuli. Cutting the syllables 200 msec after their onset meant leaving off the ends of some of the syllables; nonetheless, all stimuli sounded natural. The loops for each syllable were played on the Ampex and cross-recorded for one minute onto the Magnecord (at 7+ips) in the appropriate experimental order with 30 seconds silence between the one-minute sequences. The stimulus syllables were assigned to two groups (I and II) under the constraint that exactly half of the syllables of each type (6 CV, 6 VC, and 3 V) appear in each of the two groups. The order of the items within the two groups was then randomized. All subjects heard Group I followed by Group II. Half the subjects heard Group I in their left ears and Group II in their right ears; the other half heard the converse. This design allows direct comparison of reported changes to all syllables of a particular type (e.g., CV) as a function of the ear receiving the stimulus.5

Ten Brandeis University undergraduates participated as paid volunteers. They were native speakers of English. Two of the students were left-handed; five heard the syllables in the left ear first; the other five heard them in the right ear first. Each subject was instructed that he would hear one-minute segments of continuous auditory material, that certain sounds might be repeated over and over, but that there might also be different sounds during the course of the minute. The subject was told that his task was to imitate as exactly as possible the first sound that he heard and 4. Subjective loudness, although some function of amplitude for all signals, is not the same function for all linguistic units. Thus, keeping the amplitude constant for these stimuli meant that some sounded slightly louder than others.

5. An error was made in actually carrying out the experiment; one CV ([Pa]) was accidentally left out and a VC was played twice ([sk*I). When this error was discovered, five of the subjects were successfully recalled to listen to [t%] and five additional subjects were recruited to listen only to [the].

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Louis M. Goldstein and James R. Lackner

every new sound that occurred. He was also told to write down what he heard; but, if he could not keep up with both writing and imitating the sound changes, just to imitate the changes. The subject was then seated in the sound-insulated chamber and the experimental tape was played to him monaurally over a Grason-Stadler headset from an Ampex AGSOO at constant intensity (approximately 65db SPL). His verbal responses were recorded by means of another tape recorder. At the end of fifteen experimental sequences, the subject was given a rest period and the orientation of his headphones was reversed. At the conclusion of the experiment the subject was asked to describe the general nature of the sounds that he had heard, and whether or not they had sounded like speech sounds.

Scoring The subjects’ written and recorded responses were analyzed by two scorers. The number of times a subject reported a change in what he was hearing (transitions) as well as the total number of phonetically different forms that he reported were tallied for each subject. When a discrepancy was discovered between written and verbal report (which was rare), i.e., when someone reported a change in one mode of response, but not in the other, that change was included with those that had been reported in both modes. Phonetic transcriptions were made of all responses. The two scorers listened to each response until they could agree on a transcription. The International Phonetic Association alphabet was employed. Results All subjects reported hearing changes in the syllables to which they were listening. These changes were almost always linguistic in nature. In only six cases was a stimulus reported as becoming non-linguistic, and all six were VCs or Vs that included a low vowel. For each stimulus syllable, a list was compiled of all the phonetically distinct transforms that were reported (over all subjects) for that syllable, along with the number of subjects who reported each of these distinct transforms at least once. This list, which is presented in the Appendix, served as an across-subjects index of the frequency with which a particular, distinct transform was reported for a particular stimulus syllable.6 In all analyses below, when number of transforms of a certain type is calculated, this across-subjects index is used. 6. The number of times that a subject reported a particular transform for a particular stimulus syllable could not be calculated, since subjects often would report a pair of transforms and

say that they were ‘alternating’, for some unspecified period of time; consequently, there was no way of determining how many instances of each transform the subject heard.

285

Alterations of the phonetic coding of speech sounds during repetition

cvs In analyzing the transforms reported for CV stimuli, the responses that were meaningful English words were separated from those that were not. Of the different nonmeaningful responses to CV syllables (using the across-subjects index described above), 97 were CVs, 47 were CVCs, one was a VC, four were Vs, 16 were bisyllables; 150 meaningful words were also reported. In addition, there were 34 syllables (that were not English words) reported that had either [h] or [j]’ as their initial segment; of these, 20 ended with a consonant (i.e., they had the form h/,VC). Table 1.

Initial consonants and glides reported in transforms of CV stimuli: The number of transforms that included each consonant or glide as an initial segment is indicated. Only transforms that were not meaningfid English words are included. The critical distinctive feature dlyerences between the various subclasses of phones reported as initial segments are represented in brackets -Ph

+cons th -voice [ -cant 1 k” ts

p% ph& __ Pl 10 8 3 3

9

1

the 1 14

2

__

-_ 3

h

__

3 2

5

Stimulus syllables bt bs __ dl 2 1 2

k% k%

3

_-

1

1

5 2

4

1 --

1

Scans +voice 1 -wnt

-cons

i-cons -voice [ Scant

[EJ

-_

1 18

g

$-voice

2

J

v

1

-3

i 7. [h] represents the initial sound in ‘heed’; [j 3 represents the initial sound in ‘yacht’.

11

3

1

10

8

1 3

--

.-

1

26

--

_.-

1

1

10

1

L I

1

--

d

d3 _J

3

1

1

10

b

ii!1 1

iv

1

d.s

2

.-

3

1

5

286

Louis M. Goldstein and James R. Lackner

Transforms

of CV stimuli

often included

a change in initial

consonant.

For each

stimulus CV, transforms were grouped according to the initial phone of the transform (as in Appendix) and the number oL translorms in each initial-phone group is shown in Table I.* Tt is clear from this table that the initial consonants of the transforms differ from the consonant in the stimulus CV in a limited number of distinctive feature dimensions. Except for the few changes to [tJ, [ds], u] and [v], changes occur only in place of articulation and voicing. Moreover, the voicing changes are unidirectional: [+voice] segments are reported as either [+voice] or [-voice], but [-voice] segments are never reported as [+voice]. The changes in place of articulation may occur along either of the features ([&anterior] and [&coronal]) that describe this dimension, and there appears to be no systematic relationship between the changes in these two features. Table 2 shows the final consonants of the transforms of CV stimuli that were non-meaningful CVCs or h/j VCs. As in Table 1, phonetic systematicity is evident: Table 2.

Final consonants reported in transforms of CV stimuli. The number of transforms that included each consonant as a jinal segment is indicated. Only transforms that were not meaningful English words are included. Within brackets are presented the defining distinctive features for subclasses of final consonants of the transforms phL ph&

1

P"

[ +cons -voice -cant

th

k” icons +voice i -cant

5 1

2

tb,

thE

1

9

Stimulus syllable k”t k% bt bs

I

8

1

3

1

1

1

3 2

I 3

dt

da

2

12

1

3

kY

4

1

b

2

d

2

1 1

+cons [ +nasal I

5 1 1

1

g

t-cons -voice c tcont

f3

f

1

n ~

8. In determining the number of transforms having a particular initial segment for Table 1, transforms that are listed in Appendix as

having been reported by n subjects are counted n times in the total for that initial segment.

Alterations of the phonetic coding of speech sounds during repetition

287

The stimulus syllables that begin with unvoiced stops have transforms ending only in unvoiced stops (that also may vary in place of articulation), while stimulus syllables that begin with voiced stops have transforms ending only in voiced or unvoiced stops (with the exception of [f] reported as a final consonant in a transform of [da] and [n] reported for [gs]). Thus, for stimulus CVs with voiced stop consonants, initial and final consonants of transforms are either voiced or unvoiced stops, but for stimulus CVs with unvoiced stop consonants, initial and final consonants belong only to the class of unvoiced stops. Transforms of CV stimuli for which there is no initial consonant are also systematically related to the voicing of the consonant in the stimulus CV. For stimuli with unvoiced stops, [h] is always reported initially, while for stimuli with voiced stops, [j] is always reported initially (see Table I). From Tables 1 and 2, it can be seen that the vowel context of the stimulus consonan.t does not systematically affect the consonant changes. It is also evident that the occurrence of consonant changes is not dependent on particular perceived vowel changes because for 27% of the consonant changes in Tables 1 and 2 the vowel reported in the transform syllable was identical to that in the stimulus syllable. The vowel changes that did occur generally were limited to changes in vowel height, or tensing of the vowel with the addition of a long glide ending in a reduced vocalic segment (e.g., [bl] + [bija]). The meaningful English words that were transforms of the CV stimuli were also arranged into matrices like those for the non-meaningful transforms. The resulting pattern is almost exactly like that of Tables 1 and 2, except that [h] is found initially in transforms of voiced stops and [b] is found to change to [f] and [a] initially. Thus, these transforms are phonetically related to the stimulus syllable, just as are the nonmeaningful transforms.

VCs and Vs The systematicity noted in the transforms of the CVs for consonants is also found in the transforms of Vs and VCs for vowels. For both Vs and VCs, all types of non-meaningful monosyllables - CVC, CV, VC, V - were reported, as well as English words. The vowels that were reported in non-meaningful transforms for VC and V stimuli are presented in Table 3. As can be seen, vowels generally change in height [(&high], [& low]) and in tenseness. The change in tenseness often includes addition of a glide and a final reduced vocalic segment (e.g., [L]+[ijo]). Stimulus vowels also are reported as a reduced vowel ([a]). Rounding and front/back dimensions of the non-low vowels ([i], [E], [o], [o]) do not change (with only three exceptions), but there is some change of rounding and backness for low vowels, particularly for [o]. It should be emphasized that there is a great deal of dialectal variation in

288

Louis M. Goldstein and James R. Lackner

Table 3.

Vowels reported in transforms of VC and V stimuli. The number of transforms that included each vowel is indicated. Only transforms that were not meaningful English words are included. Within brackets are presented the defining distinctive features for subclasses of vowels

.kh tp”

1

1 skb ap” ]r

Stimulus syllables ekh aeph ze (>kh op” Q >k” oph

_-

__

+high -low -back [ -round

1 1 t

11

6

ija

1

2

9

2

2

1

2

121 1

.-

-high -low -back [ -round

1

E

eja

1

5

et

[+roundl

17

124

1 2

1

_-

I

7

41

_-

1 1

1

1

o

-_

4 3

27 11 7 1

_-

1

2

i

a1 alkh opb e

.-

1

_...

1

14 11 3

.-

_-

I

--

1

4

1

8

14

1

1 I 1 1

+high -low $-back [ + round

Q

u

3

owa

2

i

a

at

oja

1

-_ I 3

2

1 __

16 12 11

3

2 2

4

5

1

1

2

._

-_

3

1

2

.-

OQ

0

8 1

.-

-high Slow iback +round

_-

3

uwa

-high -low $-back $-round

1

.-

.-

4

--

1

5

5

8

1

.-

12

3

1

1

11

1

_-

1

2

1

4

31

3 -

2

Alterations of the phonetic coding of speech sounds during repetition

289

the pronunciation of low vowels (Kurath and McDavid, 1961), particularly along the dimensions of backness and rounding. It is of interest that this apparent scattering of responses occurs just for those vowels for which there is great dialectal variability. The consonants reported in transforms of VC and V stimuli are less systematic than any results thus far discussed. The transforms of Vs are particularly curious, since consonants are reported both initially and finally, e.g., Vs transform to CVs, VCs and CVCs. These ‘phantom’ consonants are somewhat systematic, [b] appearing as the initial consonant in transforms of every stimulus V, and [f] appearing as an initial consonant in transforms of all front V stimuli.%The final ‘phantom’ consonants, however, are apparently random. The final consonants of transforms of VC stimuli include a large number of unsystematic consonants: Nasals, voiced consonants and continuants are reported. The initial consonants for transforms of stimulus VCs do not seem to be related to these final consonants of the transforms of VCs but instead seem to be related to the phantom consonants reported for V stimuli. [b] and [f] are the consonants most often reported initially in transforms of VCs. The meaningful wards that were reported as transforms of Vs and VCs were listed in a table with a format similar to Table 3. The same general pattern emerged. Vowels were found to undergo changes in height and tenseness. Ear asymmetries The total number of transitions (the number of times a subject reports a change)lO and the total number of different forms reported by a subject, in response to each type of syllable, are presented in Table 4, separately for left and right ear presentations. The results, summed for all ten subjects, reveal an asymmetric trend in the number of transforms reported for CV and VC presentations to the left and right ears. For stimulus syllables with consonants, more transitions are reported with presentations to the right ear than with presentations to the left ear, but this does not reach statistical significance in a Wilcoxon matched-pairs, signed-ranks test. No asymmetry occurs for V presentations. In terms of the number of distinct forms reported by subjects, rather than the number of transitions, a similar trend is found. For stimulus syllables with consonants (CV and VC), more distinct forms tend to be reported by subjects for right-ear presentations, than for left-ear presentations. (For VC stimuli, a Wilcoxon matched-pairs, signed-ranks test indicates that this difference is significant, p < .05. For CV stimuli or for CV and VC stimuli grouped together, 9. Lass and Golden (1971) used the vowels [il, [ael, [ul in a verbal transformation study, and their results also show that [bl was reported as an initial consonant in transforms of all these vowels.

10. If a subject reported hearing an alternation of syllables, a single transition was scored, regardless of how long the alternating contimed.

290

Louis M. Goldstein and James R. Lackner

differences stimuli.

are not significant).

Again, there is no evidence

Table 4.

Total number of (a) transitions and (b) phonetically distinct forms reported by subjects for the three types of stimuli, as a function of the ear to which the repeated syllable was presented Number of transitions cv Left ear 445 Right ear 518

of any asymmetry

for V

(a)

(b)

Number of phonetically cv Left ear 204 Right ear 217

vc 520 678

V 216 206

distinct forms V vc 232 95 279 98

Discussion When subjects listen to non-meaningful syllables being repeated, they report a variety of changes in what they are hearing; these changes are almost invariably linguistic in nature. The restricted nature of these changes suggests that a listener’s perceptual representation of the repeated stimulus syllable is so constrained that a phonetic coding of the input is always preserved. It was also observed that the phonetic feature matrices of the set of transforms for any stimulus syllable are systematically related to one another. This latter fact is interpreted as evidence that the phonetic coding of speech is organized as a sequence of units that correspond to the phones of phonetic feature matrices, and that the phones are coded on a number of dimensions that correspond to distinctive features. The changes reported by subjects cm then be interpreted as systematic reorganizations of the units of the phonetic coding, along with changes in certain coded dimensions of these units. Evidence that there are units of the phonetic coding of speech that correspond to phones is found in the transforms of CV stimuli that were of the form CVC. For each stimulus CV, the final consonants that occur in CVC transforms constitute a very restricted class in terms of distinctive features. This restricted class is precisely the same class that is formed by the initial consonants reported in CV or CVC transforms of the same type of stimulus CV. For CV stimuli with voiced stop consonants, the initial consonants of CVC and CV transforms are stop consonants - either voiced or unvoiced - and the final consonants of the CVC transforms are also stop consonants - either voiced or unvoiced. However, for CV stimuli with unvoiced stop consonants, the initial consonants of CV and CVC transforms are always unvoiced stop consonants, and the same restriction applies to the final consonants of CVC

Alterations of the phonetic coding of speech sounds during repetition

291

transforms -they are always unvoiced stop consonants. On the assumption that there are separate units at some level in the phonetic coding that correspond to the consonants and the vowel of a syllable (i.e., to the successive phones of the phonetic matrix assigned to a syllable), the CVC transforms can be interpreted as the result of a reorganization, by the listener, of the coding units that he assigns to the input. Thus, the phonetic coding is viewed, on one level, as divided into a series of units, e.g., C-V-C-V-C-V.. ., that is initially organized into CV groupings. Reorganization of these units may result in VC or CVC groupings. On the alternative view that syllables are the minimal units of the phonetic coding of speech, the CVC transforms could not be interpreted as resulting from a reorganization of such minimal units. Syllable units could be reorganized into various bisyllabic sequences (and such transforms do occur), but syllabic reorganization could not account for the CVC transforms. A reorganization of coding units of phonetic size best accounts for these results. The transforms of CV stimuli which are reported as hVC or jVC can also be interpreted in terms of a reorganization of phonetic units into new syllables. The final consonants of the “/, VC transforms obey the same constraints as the final syllables of CVC transforms. For CV stimuli with voiced consonants, the final consonants of the jVC transforms are either voiced or unvoiced stop consonants, while for unvoiced CV stimuli the final consonants of the hVC transform are all unvoiced stop consonants. While it is not clear how to account for the appearance of [h] and [j] in these stimuli, this problem seems to be largely independent of restrictions on the final consonants, since [h] and [j] appear initially in transforms with no final consonants at all. The fact that the final consonants of those transforms are, again, of the same classes as the initial consonants of the CVC and CV transforms indicates that the units of the phonetic coding have been reorganized from a CV syllable to, essentially, a VC syllable. It is important to consider an alternative interpretation of the */,VC transforms that might explain why these transforms were reported, without postulating a phonetic coding of individual phones. The interpretation of the h/,VC transforms considered above proposed that these transforms are reported as a result of the listener’s reorganization of the units (phones) of the phonetic coding of the input into new syllables. However, it is possible that subjects are not reorganizing abstract units of a hypothesized phonetic coding but are, instead, restructuring successive aspects of the acoustic signal into new acoustic segments such that the new segments are precisely those acoustic patterns that would, in isolation, be reported as the “ijVC syllables. Such an interpretation makes no claim about perceptual codings; it assumes only that the sequence of acoustic cues presented to subjects can be segmented either into acoustic patterns appropriate for perceiving a string of CV syllables (the ‘correct’

292

Louis M. Goldstein and James R. Lackner

stimulus syllables), or into acoustic patterns appropriate for perceiving a string of h/jVC syllables. An experiment by Malmberg (1955) casts doubt on an acoustic resegmentation interpretation of h/lVC transforms. Malmberg presented subjects with pairs of twoformant synthetic syllables in which the transition of the second formant of a particular stimulus occurred either at the end of the first syllable of the pair or at the beginning of the second syllable. For interstimulus intervals above approximately 70 msecs, subjects always reported as VC-V the stimulus pairs with transitions at the end of the first syllable and as V-CV the stimulus pairs with transitions at the beginning of the second syllable. Thus, silent intervals of 70 msecs or more were heard as intersyllable silence, rather than as a silent interval preceding a syllable-final stop. The silent interval (100 msecs) used in the present experiment is clearly in the domain that Malmberg’s subjects heard only as interstimulus intervals (even though VC syllables, when spoken in isolation can have silent intervals as long as 100 msecs preceding the final burst; see Halle, Hughes and Radley, 1957). Thus, it is unlikely that subjects were ‘resegmenting’ the acoustic input, although it is possible to maintain such a view by supposing that Malmberg’s results do not have any bearing on syllable pairs that include bursts as well as transitions, or by supposing that the listener’s ability to correctly judge temporal intervals diminished during the course of repetition. Such possibilities require further investigation. Our evidence also supports the notion that the successive units of the phonetic coding are ‘subdivided’ along dimensions that correspond to distinctive features. With only the few exceptions noted in Table 1 and Table 2, the consonants of the transforms of CVs differ in only two distinctive features - voicing and place of articulation (or three distinctive features if place of articulation is considered as two binary features - [&anterior] and [&coronal]). That changes are limited to these same feature domains for all six of the stop consonants presented suggests that the consonantal units of the phonetic coding have representations along a number of separate dimensions, some of which may change independently of the others. One such dimension would correspond to the distinctive feature of voicing, and another to the place of articulation. Voicing and place of articulation must be considered separate dimensions since it is clear that either of these two features may change without a concomitant change in the other feature. Moreover, there is an asymmetry in the direction of the voicing changes but not in the direction of the place of articulation changes: Stimulus CVs with [fvoice] consonants may be reported as syllables with [-voice] consonants, but stimulus CVs with [-voice] consonants are not reported with [+ voice] consonants. l1 No asymmetry exists for changes in the place of artic11. Naeser (1972) has also noted a tendency for voiced consonants to be devoiced, as

subjects listen to words being repeated, both normal and aphasic subjects.

for

.Ilterations qf the phonetic coding of speech sounds during repetition

293

ulation dimension, and, in fact, there is no way of deciding whether this dimension should be considered as a single dimension with four separate values (bilabial, alveolar, palato-alveolar,velar) or as two dimensions ([&coronal], [&anterior]). Similarly, the vocalic units of the phonetic coding have representations along two dimensions - one corresponding to the distinctive feature(s) of vowel height, the other to tenseness. Vowels of the transforms of VC and V stimuli were found to differ only along the features [&tense], [&high] and [&low]. (Although there was some changing of the features [&round] and [&back], such changes only occurred with low vowels for which there are dialectal differences.) The feature [f. tense] ought to be considered a separately coded dimension, since vowels were reported as [ + tense] even when changes in other distinctive features had not occurred. The features [f high] and [flow] are probably better viewed as a single dimension of the phonetic coding - vowel height - since changes in those two features cannot be independent: A [+ high] vowel is always [-low] and a [+low] vowel is always [-high]. Also, Table 3 indicates that vowel heights tend to shift by one height, i.e., a high vowel is reported as a mid vowel more often than a low vowel, while a mid vowel is reported about equally often as high and low vowels, Thus, a single coded dimension of vowel height with a continuum of possible values - high, mid and low - best describes these results. Before acceptance of our phonetic coding hypothesis is possible one more alternative explanation must be considered. Our interpretation assumes that the auditory representation of the acoustic sequence does not change during repetition of the sequence. However, it is conceivable that the response of the auditory system to an acoustic sequence changes with repetitions of the sequence; the changes in a subject’s perceptual reports might then be attributable directly to peripheral auditory changes. In order to support this alternative explanation, it is necessary to specify those peripheral auditory changes that would predict the precise set of response changes observed in our experiment. All distinctive features have acoustic correlates associated with their values; however, for some distinctive features, the correlates of the opposing values are very distinct acoustically, while for others, the correlates are very similar acoustically. If the distinctive feature changes in the transforms are just those with similar acoustic correlates for the opposing feature values, then an explanation of the transforms as a result of auditory response changes is, at least, feasible. Small auditory changes could be sufficient to effect the shifts from one value of the feature to the other. (In a similar fashion Clegg, 1971, has argued that transforms are simply errors in perceiving the repeated syllables - errors that would be made by subjects even if the syllables were not being rapidly repeated). The changes along the place of articulation dimension that were observed in the present experiment could possibly be explained as resulting from small auditory response changes. Miller and Nicely (1955) asked subjects to identify CV syllables

294

Louis M. Goldstein and James R. Lackner

(all with the same vowel), presented either in white noise or after band-passing. Perceptual confusion matrices showed that consonants were much more often misidentified on the place of articulation dimension than on the other dimensions investigated (nasality, voicing and affrication). This suggests that the acoustic differences between consonants differing only in place of articulation may be quite small with reference to the human auditory system. Thus, small changes in the response characteristics of the auditory system might lead, in the repetition paradigm, to the perceived changes that were reported along this dimension. Two types of commonly reported perceptual changes - the devoicing of consonants and the tensing and diphthongization of vowels - cannot, however, be readily attributed to changes in peripheral auditory response. It is unclear why the acoustic correlates of voicing, tensing or diphthongization would be particularly affected by any simple changes in auditory response (e.g., adaptation of frequency-specific receptors). Moreover, a specific uni-directional change in peripheral response would have to be postulated to account for the observed asymmetry in voicing changes. There is currently no independent evidence for such a restricted, directional auditory adaptation. Thus, while changes in peripheral auditory response may well contribute to the verbal transformation effect, it does not seem that all of the particular types of reported changes can be explained solely on the basis of such adaptation. In summary, the phonetic coding assigned to a repeating input changes over time; these changes appear to be the consequence of two factors, a reorganization of the successive units of the phonetic coding into different syllables, and an alteration in the individual units themselves. These units of the phonetic coding can be viewed as corresponding to the phones of the phonetic feature matrices assigned to utterance and as being coded along dimensions corresponding to at least some distinctive features.12

12. Wickelgren (1966) has presented independent evidence from studies of short-term

memory that CV syllables are coded as clusters of distinctive features.

Alterations of the phonetic coding of speech sounds during repetition

295

Appendix Complete list of transforms for all stimuli. For each repeated syllable (numbers l-30), the list includes all of the phonetically distinct transforms that were reported (across all subjects). The number next to a transform indicates the number of subjects who reported that particular transform. Transforms without numbers were reported by one subject only. Responses that were not meaningful words in English ate represented in phonetic transcription, using the International Phonetic Association system. Meaningful English words are represented in conventional orthography.

1. 2. 3. 4. 5. 6. 7. 8.

9. 10. 11. 12. 13.

p4

- p%e, p%-2, ‘phijo-2,’ thija, t%, hs, ht-2, ‘pheath, p’t’dae, pht’dsr, plo, pht’ds, ptithze, tht’dse, t, pear, pier, pick, hip-2, hair, hick, hear, pip. ph& - p”a, ‘phija-2, ‘p”eja, pht, haeph-2, khs, khsph, thcph, phi&eph, ‘phikhsth, hs-3, phi’jath, pap, pep-4, hep-5, hat, cat, the cat, pet-2, pat-2, happy-2. bt - ‘bija-7, bs, ‘bijath, ’vija-2, ‘vijtph, japh, j&p”, t-2, ‘bi’jath, beard-2, beer-3, bear-2, be happy, be it, there-3, here, happy, can o’beer. bs - bae-6, ‘beja-2, ‘bejath, vae-2, ‘bejath, phejath, bear-3, beer, bat, there-$ that, happy, thing. tht - ‘thija-5, ‘t”eja, ths, tha, thcph, ~~1-2, ‘phija, tJt, tJ, tJa, ht, hc, tit-3, tip-6, tear, peer, hit-5, hip-4, hips, hair, shit, ship-2, shape, pit, pip. ths - thsph-4, thz-4, thaeth-3, thsth-2, Ithijath, phs, haeph, hsth-2, tear, tap-4, cat-2, cap-2, pack-2, pet-2, hep-2, hat-2. dt - ‘dija-7, ds, dae, da, ‘dijaph, dsph, dtb-4, ‘dejath, ‘deja, dar-2, Adi, jreb, jz, jt, ja, ‘phija-2, dip-5 did, peer, here, deer-2 dab. ds - die-3, dt-3, da-2, dleph-4, dazth-2, daef, ‘dejath, dsb, dsph-5, ‘dijaph-2, daq ‘dijab, ‘t”ija, ths, ‘theja, jsb, jab, japh, ‘p’ija, gzf, dab, dip, dare-2, don’t, deaf, tap-2, cap, happy. kht - ‘khija-3, kha, tJt, tJa, Jt, ht, tht’khtth, kht’thtkh, kit-3, kick-6, can’t, chick-2, shit, tick-2, pick, hick, hit-3. kha - khz-2, khEth-2, thzeth, pht, phs, ha, rekh, a, can’t, cat-6, cap-2, ken, can, tap-4, pat, hen. gt - ‘gija-5, ga, gtb-2, gid-2, ‘dija-8, dt, di, ‘dijath, ‘dgija, ‘khija, ‘t”ija, ‘phija, ‘bija, jt, gear, give, gig, did, deer, jab. ge - ga-2, gsn, greth-3, gaekh, da, ‘deja, thzth, jeep”-2, jseb, jzth, jaeg, ‘phija, ‘diIjreph, ‘gijreph, gap-4, gidiyup, dab, tap-2, yak-4, bag, cap, cat, gab-5. tkh - t-6, 0, tg, tr, ‘ijakh, dt, ftf, jtkh, if-3, ear, here-3, fear, near, the, eater, Peter, Dick-4.

296

14.

15.

16. 17. 18. 19. 20.

21. 22.

23. 24.

25. 26. 27. 28. 29. 30.

Louis M. Goldstein and James R. Lackner

tph - ‘ijo, tb-2, IV,ja-2, btf, jtph-2, ‘gijaph,japh-2, jakh, dzp”, ‘eja, a, jakh, ‘p”i’joQ, ‘aphIdi, if-5, dip, gidiyup, fear-2, hear-2, amp, ampere, pear. skh - (1) E-S, ‘eja, t, a, af-2, na, szkh, hs, fa-2, ‘khejo, ‘thejo, hr, ‘hijo, khskh, slfath, heck, deck, effect, gidiyup, act-2, at-2, that, bat-2, fat, happy, don’t, back, fare. (2) a-7, ‘ejo, z-3, a, sf, at’, rekh-2, bae, ‘bejaP, ‘s’fath, heck, peck, deck, debt, at-3, that, back-2, pack, bat-2, can’t, act, fat, don’t, happy. &ph - a, ‘eja, sf-3, reph-3, aph, fa, daQ, fs.ph-2, daph, f&b, ‘hphdet, khsth, fsth, dreph, depth, at-4, bat-3, that, fat, cat, doubt, ebb-2, out, cut. zekh- z-6, ‘ejo, ‘ija, aeph-4, bae-2, ‘Aphdet, ba’dre, bzph, ‘aja, at-g, bat-4, path, fat, bath, knock. zph - z-3, ~-2, ‘eja, a, 0, reb-2, a?f, &ph,baz-3, bra, dao, bE, ‘beja, ‘bija-2, brcph, haja, at-4, add, gap, happy, bat, fat, out-2, doubt, bout, bow, act. okh - o-5, a, at, re, E, a, ag, ath, Qth, dot, fakh, awa, ought-4, got, bought, off, bon (Fr.), art, are-3, on-4, bark, Ethel. oph - 3, a, 0, og, aph, ab-2, ath, bo-3, fo, ma, ba-2, Ibeja, boph, bab, bath, ‘boja, bought-3, ought, off-4, bar, ma, bog, fought, awful, mark, on-3, buy, Ethel. okh - 00-10, on, an, phoQ, khoQ, VOQ,ga, ba, gon, ooga, uga, ‘phoQ’khoQ, go-7, bow-4, gold, boat-a, oak, don’t, foe. oph - oQ-10, oQb, ogk, on, Qg, gog, won, doon, bog, bQm, gag, Oan, uga, bow-4, bowl-2, gold, go-2, goal, don’t-2, vote, full, gunk, funk, bubble, sung, sunny, sun, bulb, tongue, tungsten, bunk, dink, bowlful. okh - Q-2, 3-2, Iowa-5 OQ, oth, okh-2, akh, khoQ, book-3, guk, ought, got, dot, dock, balk, gawk, dog, talk, bought, coat, toke, toe. Qp” - Q-2, u, a, 0, oQ, Qf, okh, OQth, fQ, fo, ho, fQph, WQph, fQf, ‘fQkh&, fokh, book-2, woof-2, puller, look, poor, hawk, paw, football, doctor, claw, know, tow, folklore. 1 - ‘ija-6, ‘eja, ‘bija, ‘hija, ‘fija, ear-3, here-3, dear, fear, bear, her. & - ‘eja-5, et, a, a, I, &ft, Ef, bE, jE-3, f&, ‘t”eja, ‘beja,jt, ‘hija, ‘bija, hetna, bear, there, air, fare, hair, at, dance, hear, ear, air fare. a: - a-2, ‘eja, ‘ija, i, rekh, zeph, an, tg, ba, fs, Ikheja, ‘t’eja, ‘bejath, at-2, bat, fare, air-2, more, happy, pear. 0 - a-8, ‘eja, a, ag, ath, ba, tha, na, da, baph, saw, off, bought, a thought, an awful lot, far. 0 - 00-9, owa-2, oob, ‘bola, ‘pholo~, go, ohm, pole, poem, bowl, oak, bow-3, follow, all, ball-2, fall, full, pull, funnel, bulb, bowlful, boa. Q - ‘uwa-2, OQ, 3-3, a, a, ‘thowa, go, 0, bc, Iowa, ‘bQla, Iowa-2, blow it, bow it, for, four, floor, whore, nor, more, tow, bullet, boa-2, bore, or-3.

Alterations

of the phonetic

coding of speech sounds during repetition

297

REFERENCES Chomsky, N., and Halle, M. (1968) The soaud pattern of English. New York, Harper and Row. Clegg, J. M. (1971) Verbal transformation on repeated listening to some English consonants, &it. J. Psychol., 62, 303-309. Halle, M., Hughes, G. W., and Radley, J. P. A. (1957) Acoustic properties of stop consonants. J. acoust. Sot. Amer., 29, 107116.

H., and McDavid, R. (1961) The pronunciation of English in the Atlantic states. Ann Arbor, University of Michigan

Naeser, M. A. (1972) The repeating word effect: Analysis of alternates reported by aphasics and normals. Paper presented at the tenth annual Academy of Aphasia meeting, Rochester, New York. Perkell, J. S. (1971) Physiology of speech production: A preliminary study of two suggested revisions of the features specifying vowels. M.T.T. Research Laboratory of Electronics, Quarterly Progress Report

Kurath,

Press. Ladefoged,

P. (1971) Preliminaries to linChicago, University of Chicago Press. Lass, N. J., and Golden, S. S. (1971) The use of isolated vowels as auditory stimuli in eliciting the verbal transformation effect. guistic phonetics.

Can. J. Psycho/.,

No. 102, 123-139.

Studdert-Kennedy, M., and Shankweiler, D. P. (1970) Hemispheric specialization for speech perception. J. acoust. Sot. Amer., 48, 579-594.

Warren, R. M. (1961) IlIusory changes in between repeated words : Differences young adults and the aged. Amer. J. -

25, 349-359.

Liberman, A. M., Cooper, F. S., Shankweiler, D. P., and Studdert-Kennedy, M. (1967) Perception of the speech code. Psychoi.

auditory perceptual mechanisms.

80-87.

Psycho/.

-

and Gregory, R. L. (1958) An auditory analogue of the visual reversible figure. Amer.

-and

J. Psychol.,

71, 612-613.

Warren, R. P. (1970) Auditory illusions and confusions. Sci. Amer. 233, 30-36.

Miller, G. A., and Nicely, P. E. (1955) An analysis of perceptual confusions among some English consonants. J. acoust. Sot. Amer.,

effect and

BUN., 70,261-270.

Rev., 74, 431-461.

Malmberg, B. (1955) The phonetic basis for syllable division. Studia Linguistica 9,

Psycho/., 74, 506-516. (1968) Verbal transformation

27, 338-352.

Wickelgren, W. A. (1966) Distinctive features and errors in short-term memory for English consonants. J. acoust. Sot. Amer.,

39, 388-398.

Rkumk

Un des aspects de la comprehension de la parole consiste a assigner une representation phonetique aux sons entendus. Cependant, lorsque une syllabe sans signification est rep&e de facon continue, l’tcouteur, apres un certain moment, entend cette syllabe avec des modifications diverses. Ces modifications ont un caracttre systematique et representent

les alterations du codage phonetique assign6 a un stimulus auditif constant. Quand on analyse phonetiquement la nature de ces variations, on remarque qu’elles impliquent une reorganisation des phones constituant les syllabes et des alterations d’un petit nombre de traits distinctifs.

3

Semantic

components

and conceptual

JONATHAN McMaster

development*

BARON

University

Abstract Several phenomena in the acquisition of word meanings may be accounted for by a theory of component-by-component acquisition, a mechanism analogous to that proposed for phonological development. By defining a concept as an habitual plan, and a component as a subplan, we may extend this theory to acquisition of concepts in general. This theory may be applied to logical concepts, physical reasoning and moral reasoning as well as verbal concepts. The ideas of component-by-component acquisition and of transfer of learning between concepts sharing components thus provide an alternative to deveIopmenta1 stage theories. Recently several attempts have been made to extend Jakobson’s (1942) theory of phonological development to the development of verbal concepts (e.g., E. V. Clark, 1971, 1973; Donaldson and Wales, 1970; McNeil& 1970; Menyuk, 1971). This work rests on the analogy between semantic features or components (as defined in various ways by Bierwisch, 1967; Chafe, 1970; Goodenough, 1956; Katz and Fodor, 1963; and Lamb, 1964) and phonological features. The essence of this extension is the idea that verbal concepts may be acquired one component at a time, and that in many cases a single component which extends across several concepts will be learned at about the same time for all of them. For example, Donaldson and Wales (1970) found that many young children respond to the word ‘less’ as if it meant ‘more’ in contexts like, ‘Show me which one has less’, and that manyofthese childreninterpreted ‘short’ as ‘tall’, ‘wee’ as ‘big’, and so on. H. Clark (1970) has suggested that * Lee Brooks, Eve Clark, John Gibbs, Betty Ann Levy, Dave Meyer, Dan Osherson, Linda Siegel, the journal referees, and others made valuable comments on earlier drafts. To save space, some of their criticisms are left un-

answered for now. None has so far endorsed the views expressed. Financial support was provided by a grant from the National Research Council of Canada. The author is now at the University of Pennsylvania. Cognition 2( 3). 299-317

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these misinterpretations result from the absence of a single component of the meaning of the terms in question, which I shall call the ‘antonym’ component. The purpose of this paper is to show how this sort of component theory might be extended still further to explain (eventually) all phenomena in which systematic errors are made in the acquisition of concepts, nonverbal concepts as well as verbal ones. Such an extension will require a redefinition of ‘concept’ and ‘component’ as, roughly, ‘habitual plan’ and ‘subplan’ respectively. The range of phenomena that can be explained in this way is similar to that accounted for by developmental stage theories such as that of Piaget (e.g., 1970). While Piaget would argue that cases of systematic error usually exemplify absence of skills or structures, such as understanding the reversability of operations, which could affect areas of intellectual development, component theory would hold that the skills involved are less general. For Piaget, practice at a particular task might strengthen all of the structures involved in the stage that task requires, while for component theory, practice would strengthen only the components used. The idea that a concept is an acquired habitual plan follows from the analogy (see Miller, Galanter and Pribram, 1960) between human information processing and the operation of a digital computer. If we look at concepts in this way, we must define a concept in terms of a task in which the concept is used. This contrasts with the usual view of concepts as categories defined by relations between perceptual attributes and a single response (Bruner, Goodnow and Austin, 1956). However, even artificial concepts may easily be seen in terms of plans; Trabasso, Rollins and Shaughnessy (1971), for example, have shown how classifying a stimulus may require a strategy in which successive decisions are made, each step requiring examination of a perceptual attribute. Concepts are habitual in the sense that they are evoked by a particular stimulus or situation without additional thought about what to do, that is, without the use of plans to construct plans. Further, the same plan will be likely to recur in the same situation. Concepts may be contrasted on the one hand with instinctual plans, which are ‘wired in’, and with ad hoc plans on the other. Ad hoc plans may in fact use concepts as subplans, or use some of the same subplans as concepts use, except that they are created for the situation at hand, possibly with the use of special plans to create plans (which themselves may use acquired concepts). A plan may be analysed into subplans, which may in turn be analysed into other subplans, and so on (perhaps ending at some level of subplans analogous to machinelanguage instructions in computer programs, each of which must occur as an indivisible unit). We shall assume that subplans may be recombined in various ways, and that a given subplan does not change in character when it occurs as part of different concept plans. To pursue our analogy with Jakobson’s theory, the subplans

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301

correspond to the features or components which are recombined in various ways to produce phonemes. This analogy breaks down, however, in two respects: First there are surely many subplans which are used only for one concept, but each phonemic feature is used in several phonemes; second, concepts may be organized into a hierarchy with some concepts acting as subplans of other concepts. I should note that the analogy between components and computer subroutines is also imperfect. First, I do not assume that the component subplans are executed in series, since it is possible that several of them are executed simultaneously. Second, the subplans may take certain forms that are not characteristic of computer programs. For example, one type of component may instruct some mechanism to allow itself to be intluenced only by a certain dimension, such as number, when it could be influenced by other dimensions such as length without such instruction. This kind of component may distinguish concepts of number, for example, from those of general size or ‘bigness’. Thus, subplans may set the parameters of attention as well as carry out acts. Component theory accounts for systematic errors as failures to use a subplan that would be part of the mature use of the concept. Failure may occur for two reasons. The first is that the subplan is not available for use as part of any concept at the time it is required, possibly because it is difficult or poorly learned; I shall call this a strategy error. The second reason is that the learning which associates the subplan in question with a situation or word may be weak, and, even though the subplan may be available, it is not brought into play; I shall call this an attachment error. Often a subplan may be omitted without jeopardizing the completion of the entire plan. In other cases, perhaps most, some inappropriate subplan may be inserted, and each possible subplan of this sort will be chosen with some probability regardless of whether each is appropriate or not, as long as it allows completion of the plan. In many cases, errors resulting from completion of an inappropriate plan will be identical to responses that would be appropriate in some other situation. For example, omission of the change in response-choice required for ‘less’ in Donaldson’s and Wales’ (1970) study would be appropriate for ‘more’. In such cases, I shall speak of assimilation of the first concept to the second. So far, component theory has led to only one prediction of interest; we ought to be able to describe most conceptual errors as omissions of identifiable subplans and retention of others, rather than completely random responding. Other predictions may be generated by adding the simple assumption that practice at using a subplan as part of one concept (such as the antonym component discussed above) transfers to uses of that subplan as part of other concepts. This may occur in two ways, corresponding to the two types of error just described. First, practice at using a subplan may strengthen the subplan itself. Strategy errors would decrease in the early stages

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of such practice, but, even after such errors had disappeared, the use of the subplan could still improve in the sense that it would require less time or attention. Second, practice at attaching a subplan to the appropriate plan could make it easier to attach similar subplans to other plans. (This mechanism is discussed further by Baron, 1974.) One way of looking at this second mechanism of transfer is to assume that each concept has a characteristic executive routine which calls up the various subplans in the right order; each subplan is thus represented in the executive routine. Practice at representing a subplan as part of one executive routine would thus transfer to representing that subplan as part of other routines. In general, then, we would expect transfer of practice between two concepts to the extent to which the two concepts have similar subplans. There are two consequences of this transfer assumption which are of particular interest in the study of development. First, if a number of concepts share a common component, learning to use one will facilitate learning the others. If we examine a set of concepts which have a few such common components, we might see develop mental stages in the acquisition of the set. Each stage would correspond to the acquisition of one or two new components and their generalization across the set. Second, unlike stage theories, component theory makes no particular predictions about the order of acquiring components. Certain subplans will surely be more difficult than others, and in some cases subplans will not be learned until their own components have been acquired. However, in many cases we would expect to see components learned in different orders depending on the particular experiences and capacities of the learner. In the extreme case, people growing up in one culture may not be exposed at all to the opportunity to learn components used frequently in another culture and vice vema (see Greenberg, 1966). Thus individual differences in the acquisition of concepts within a culture may be analogous to differences between modal developmental sequences in different cultures.

1. Development of word concepts

While there is at present little evidence of precisely the sort designed to compare component theory to other theories, there is a great deal of evidence consistent with the theory. Thus, the best way to argue for component theory as a viable approach may be to describe this evidence from the point of view of the theory, trying to show along the way which components may be absent in each case of systematic error. The phenomena most amenable to this sort of description come from studies of the development of word concepts in children. E. Clark (1971) for example, asked children to act out instructions containing ‘before’ or ‘after’ (e.g., ‘Before the boy

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303

[doll] jumped the gate, he patted the dog’). The youngest children simply ignored the conjunction and performed the actions in the order they were mentioned. A group of older children carried out the instructions correctly when they contained ‘before’, but for ‘after’ they either continued to use an order-of-mention strategy or else treated ‘after’ as if it meant ‘before’. In this example, both the order-of-mention strategy and the ‘before’ strategy may be seen as ways of filling in the plan so that it can be executed. They are both ways of specifying which action to do first. Apparently, the ‘before’ strategy is acquired before the ‘after’ strategy; possibly the ‘after’ strategy is represented as a modification of the ‘before’ strategy, in which the actions are reversed. Clark (1971, 1973) also notes that her findings agree with those of Donaldson and Balfour (1968) concerning the meaning of terms such as ‘more’ and ‘less’. Again, children seem to pass through a stage in which they take ‘less’ to mean ‘more’ in a variety of tasks, such as saying which of two trees has more (less) apples, or making a single tree have more (less). Donaldson and Wales (1970) extended these findings to other pairs of antonyms, such as ‘same-different’ and ‘tall-short’. In no case was the meaning of the negative term learned first. These findings suggest that a component is added to most of the concepts which use it at the same stage of development; most of the distinctions based on the ‘antonym’ component seem to be acquired within a couple of years of the first such acquisition. Similar findings from Russian literature concerning the meaning of spatial prepositions such as ‘over’ and ‘under’ are cited by Clark (1971) and by Menyuk (1971, Ch. 6). Baron and Kaiser (1973) have recently completed a study which illustrates the independence of the acquisition of different components. Children’s knowledge of pronouns was tested in a situation involving an experimenter, a child and two dolls. The children were told to do such things as ‘give (me, yourself, him, her, us, etc.) some pants’, or to ‘show me (my, your, their, etc.) feet’. Most errors involved assimilation of first to third person (e.g., responding to ‘us’ as if it were ‘them’), or of plural to singular. Errors on person thus seem to be due to absence of subplans which direct the required action toward individuals distinguished by certain cues, such as who has just spoken to whom. Errors on number involve the parts of the plan which provide rules for deciding whether to stop or continue the action. Each of these errors tended to occur across several pronouns and tests, and different children tended to make different types of assimilations consistently. This finding supports the prediction that components correspond to ‘factors’ within a semantic field within a language. In all of the cases described so far, the task has involved carrying out some action in response to verbal instructions. The strategies are thus expressed directly in the action, and errors are often categorized according to the stimulus that would have

304

Jonathan Baron

been appropriate for the action done. In other cases the task may involve producing a word, or saying whether or not a word is appropriate to a situation. Here the strategy may involve selecting relevant cues from the situation, possibly using information from these to select other cues and ultimately producing or verifying the word. Some. times the ‘situation’ may be provided entirely or in part through verbal description so that a verification task may require attention to purely verbal aspects of the situa. tion. Thus, different strategies may be involved in action tasks like those described above, word-production tasks and verification tasks. The component subplans 01 verbal concepts are not entirely determined by the word but by the task as well. We could not necessarily expect a child who could ‘make it have less’ to be able to ‘tell me whether it has less’, although clearly there may be components common to the two tasks, such as the antonym component. In general, results from production and verification tasks are similar to those from action tasks. Both Clark (1971) and Donaldson and Wales (1970) noted, for example, that terms like ‘after’, ‘less’, and ‘smaller’ are acquired later in spontaneous speech and verification tasks than the corresponding terms without the antonym component. Another example is based on an observation made by Bennett (1969) that words such as ‘over’, ‘through’ and ‘across’ can have two meanings. For example, ‘the tree across the road’ can mean either ‘across the road from someone’ (who may be specified) or ‘lying across the road’. In the first sense, three arguments may be specified (tree, road, specified person), while in the second sense, two (tree, road). The first sense may thus be said to use an additional component which allows specification of what the object is across (over, etc.)from. Reich, Rice and Schneider (1972) asked children to select pictures illustrating such sentences as ‘The tree is across the road’ from a set of distracters. Young children had greater difficulty with pictures illustrating the three-argument form. Thus, the simpler two-argument form seems to be acquired first. The principle governing the growth from two to three arguments may be at work in an earlier transition from a one- to a two-argument interpretation of relational terms. Piaget (Flavell, 1963, pp. 276-278) found that young children could not think of themselves as their brother’s brother, and often asserted that if there were two boys in a family, only one was the brother. These and similar confusions have been interpreted as showing that the child thinks of terms like ‘brother’, ‘left’ and ‘darker’ as defining classes rather than relations. According to component theory, he may be said to lack the subplans used for making inferences from relational statements, for example, knowing that ‘brother’ is a reversible relation, unlike ‘father’. (Haviland and Clark, 1972, have recently proposed a similar, and more extensive, analysis of acquisition of kinship terms in general.) A somewhat more subtle component has been investigated by Asch and Nerlove

Semantic

components

and conceptual development

305

(1960). They noted that a number of terms exist which can describe human character, in one sense of their meaning, and inanimate objects in another sense, such as ‘bright’, ‘dull’, ‘hard’, ‘warm’, ‘cold’, etc. The first sense seems to be acquired after the second for all of the terms. There is a rapid increase in proper use and understanding of such character terms between the ages of 7 and 10. A six-year old, for example, is apt to describe a ‘bright’ person as ‘someone who is covered with gold paint’. The use of only terms with double meanings in this study must be considered valuable only as a control for knowing the term itself. It is by no means claimed that the two meanings of ‘bright’ differ only in a single component. But it does seem plausible that the various character terms do share a common component. Once the child learns to attend to cues of character, possibly, he might begin to use all of these terms in this sense. Learning lexical concepts component-by-component occurs in ‘babytalk’ as well as in the acquisiton of adults’ concepts, even when the meanings of words are so idiosyncratic that they are incomprehensible to all but the child’s parents (see Clark, 1973, for a thorough review). Menyuk (1971, Ch. 6) analyses an example of Lewis’ (1963) in which a child’s lexicon grows by addition of features. Initially, the word ‘tee’ is used to refer to all animals (nonhuman, animate). Next, a new word, ‘goggie’, is used to refer only to small dogs and toy dogs (nonhuman, animate, doggy). The next new word ‘hosh’ is applied to large dogs and horses (nonhuman, animate, large). Finally the word ‘biggie-goggie’ is used to refer to large dogs, distinguishing them from horses (nonhuman, animate, large, doggy). Meanwhile, the child has recognized other components which allow him to distinguish between various other animals, such as ‘pushie’ (nonhuman, animate, cat), and so on. Ingram (1971) has provided a component-theoretical account of several reported examples of children’s very first words and gestures. He notes that the small number of components used to define these early words may be responsible for the frequently reported occurrence of ‘over-generalization’ in the use of early words. For example, one child used ‘ba-ba’ to refer to herself, other people and the cat, that is, presumably, animate objects in general. Then ‘dada’ was used for all men, and later for father only. Each new restriction on the use of a word can be accounted for by the addition of a component to its meaning. From the account just given, it might appear that the range of reference of a word must always become smaller when a new component is added to its meaning. This would be true if all concepts were defined by simple logical conjunction of their components (i.e., if the decision were based on a logical ‘and’ relation), but this is not always so, as components may be added disjunctively (a logical and/or relation). For example, ‘food’ may refer first to what is actually eaten, such as pork. Later, ‘food’ may also refer to animals from which the food comes, such as pigs. Here a

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Jonathan Baron

disjunctive component, which we may abbreviate as ‘precursor of’, may be added. To use this new component, a child would have to recall his knowledge that pork comes from pigs. In another sort of case, ‘doctor’ may first be restricted to male physicians. Later, a new concept may be learned in which these particular attributes do not have to be tested to apply the concept. Yet the old concept may remain alongside the new; many holders of Ph.D. degrees have been known to refer to physicians as ‘real doctors’. This is not to say that a concept is never relearned from scratch, but rather that many examples in which texts of certain attributes appear to be dropped (see Saltz, Soller and Siegel, 1972) may result from the addition of components or new concepts. Some of these subplans used in verbal production, such as those which allow us to follow rules of agreement, may require attention to what has already been said or to some representation of what will be said. Other subplans require attention to the representation of intended meaning. It would seem likely that these two kinds of subplan ordinarily operate in parallel. Table 1 shows some selected errors made by children and college students, categorized according to whether the subplan omitted seemed to involve meaning or not; those that do not are often violations of grammatical rules involving selection or subcategorization (Chomsky, 1965). What is of interest here is the appearance that most of these errors may involve a single component, a failure to execute the subplan which directs attention to some aspect of the situation.

Table

1.

Selected errors in child language and essays of college students (correct form in parentheses when needed)

Child language’ Non-semantic

That’s too bigger for you. Me do it. Me do rolls first, Mama. I want many soap. Violin tired. Piano sleeping. A your car. A my pencil. More wet. More outside. Allgone sticky. Semantic examples discussed throughout

text

1. Examples are taken from Menyuk (1971), Brown, Cazden, and Bellugi (1969), Schle-

singer (1971), and unpublished observations A. Kaiser and J. Baron.

of

Semantic components and conceptual development

307

Student pupers Non-semantic

Education beings for the child as something adults make them do. . those on which (whom) he depends. . . to make inferences onto (about) the population ..

. .. if a mother may be absence(absent) .. . . .. I have chosen to critically analysis . .. Semantic2

White has refuted (rejected) Watson’s behaviorism . . . . . . as Levinthal has demonstrated (suggested), we must consider . . . This again can be proven (supported) by Cohen’s article . . . In order to prove (test) her theory . . . His subjects had pre-conceived emotions (attitudes) concerning . . . This may infer (imply) that . . . 2. Note that the first three examples here stem to involve a component distinguishing

doubt from presupposed certainty. to be a common sort of error.

This seems

Errors which appear to involve meaning, such as substituting ‘prove’ for ‘support’ may arise in two ways, depending on whether the intended meaning is correct or not. If the intended meaning is correct, the error may simply involve retrieval of the appropriate word. The student may realize that some doubt is involved in the situation he is describing, yet this knowledge will not be sufficient to rule out his choice of ‘prove’. Alternatively, the student may construct an incorrect ‘nonverbal’ representation of the situation and may think that there was in fact no possible doubt. Only other tests could allow us to distinguish these possibilities. Even in the case of an incorrect nonverbal representation, however, training in choosing the correct word may force the student to attend to the relevant features of the situation, and may thus be a useful teaching technique. 2. Development of physical and logical concepts In addition to verbal concepts, component theory may also explain a number of phenomena which have previously been explained by Piaget (e.g., 1970) and his followers as manifestations of stages of intellectual development. A number of these phenomena concern making comparative judgments along various dimensions. Young children are often unable to make such judgments along one dimension when some other dimension is inconsistent. For example, one row of beads may be longer than another, but they might have the same number of beads. A pre-operational child, asked whether both rows have the same number, will answer that the longer row has more. He will do this even if he observes the relative lengths of the rows being manipulated before his eyes. Likewise, given a row of three beads which is longer than a row of four, he might hold that the former has more beads.

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This error may not be ‘strictly verbal’, as similar errors are made when the child is asked to choose the row of candies he would rather have (Mehler and Bever, 1967). Thus the deficit may be to a large extent due to the strategy that is evoked by both the word and the nonverbal task. Component theory can explain this kind of confusion by postulating a primitive concept of ‘bigger’, from which ‘longer’ and ‘more’ are differentiated by the addition of components. Originally, all specific dimensions of the stimuli are relevant to ‘bigness’; this simple strategy of letting all information determine the response works fairly well because usually only one specific dimension is relevant at a time, or else several are correlated. But when dimensions are in conflict, that which happens to b- most salient captures the response mechanisms. The components which must 1-e added to differentiate ‘longer’ and ‘more’ from ‘bigger’ are those which restrict attention only to certain dimensions. These components are analogous to those which distinguish ‘I’ and ‘you’ from ‘someone’ (Baron and Kaiser, 1973). In the case of pronouns, a response mechanism is directed by the specific component; in the case of dimensional concepts, an attention mechanism is directed. While ‘bigness’ will suffice for the young child, eventually the occasional need for specificity will encourage learning new components. Thus, Gelman (1969) was able to teach children to differentiate length and number easily when the two were put into conflict and the child had to attend only to the correct dimension. This account is relevant to a study done by Lawson, Baron and Siegel (1974). Children were asked whether one of two rows of dots was longer and whether one had more dots. For some stimuli, a wrong answer for one dimension might be right for another; for example, a child might say that rows of different number but the same length had the same number. If children assimilated both concepts to ‘bigger’, we would expect children to answer most questions according to the physical dimension of these stimuli that was most salient for their concept of ‘bigger’. If the relative salience of length and number differs for different children, we would expect a negative correlation across children between the tendency to assimilate length to number and the tendency to assimilate number to length; children who were correct on length would tend to treat number questions as length questions, and vice versa. Such a correlation was found. This confusion of length and number might slow down the acquisition of conservation of number. Conservation may depend on the acquisition of a new strategy in which constancy of number is inferred from the observation that nothing was added or taken away. The development of this strategy may depend on experience with transformations of actual arrays; the child would apply number estimation strategies and then the new strategy of inference, and eventually come to realize that the old and new strategies always gave the same answer, so that the new inference strategy

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could be used reliably as a shortcut. But if the child’s strategy for number estimation is based on ‘bigness’, the inference strategy will not work, as the child will ‘find’ that number can be affected even when nothing is added or taken away. If ‘bigness’ involves an ordering of the salience of cues, systematic assimilations of one dimension to another will reflect this salience hierarchy. Thus, such assimilations should be transitive: If questions about dimension A are answered as if it were B, and questions about B as if it were C, then questions about A should be answered as if it were C when the C test is applicable. Osherson (ca. 1971) has tested a number of such predictions of transitivity by searching the experimental literature on preoperational children and has found transitivity to hold in a large number of cases, even though different children were often used for different tasks. For example, preoperational children say that one object moves faster than a second object if the first one finishes in front, regardless of curves in the path of the second which actually make its path much longer. These children also assert that faster objects travel a greater distance than the slower ones, even when information about time is lacking. From these two beliefs, we may infer that these children will also hold that if one object has finished in front of another, then it must have travelled a greater distance, regardless of information about the paths or starting points. This prediction, and others like it, are supported. Thus, questions about speed are answered with respect to position, questions about distance are answered with respect to speed and questions about distance are answered with respect to position. We could infer that the normal hierarchy of cues is position, speed, distance, in that order. The view that such transitivity results from a hierarchy of cues for a single concept (probably not identical to ‘bigness’, but analogous) contrasts with the theory of such transitivity which ascribes it to internal consistency of the child’s logic. Osherson’s conclusions are formally the same as those of a study by Clark (forthcoming) in which children were asked to place one object ‘in’, ‘on’ or ‘under’ another, with two responses possible for each test. Here, when both responses in question were possible, ‘under’ was assimilated to ‘on’, ‘ on’ to ‘in’ and, as predicted, ‘under’ to ‘in’. In this case however, it seems likely that more than one primitive concept may be involved. Several other findings may be explained on the basis of assimilation to primitive concepts without certain critical components which require particular strategies of inference or attention to particular cues. Ervin-Tripp and Foster (1960) found that children tended to treat ‘good’, ‘pretty’ and ‘happy’ as synonyms for the purpose of categorizing faces. The same children also confused physical dimensions such as weight, strength and size. Bruner and Kenney (1966) found that young children assimilate ‘which glass is fuller?’ to ‘which glass has more water?‘, while older children judge fullness as a proportion, Likewise, Piaget, has noted (Flavell, 1963) that pre-

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adolescent children assimilate probability, a proportion, to frequency. In a similar vein, Smedslund (1963) has noted that adults often assimilate the concept of correlation to that of joint-frequency, and Kahneman and Tversky (1972) have described several situations in which adults seem to assimilate probability to ‘representativeness’. Logical reasoning may also be broken down into components which may be acquired independently. Here each component may be a subplan involving a certain kind of inference. Such subplans may be acquired independently of knowledge about their application to particular content areas, and independently of each other. One such subplan might be the ability to make inferences based on transitive relations such as ‘longer than’ or ‘equal to’. In a study done by Osherson (forthcoming), for example, 7 out of 8 children who failed on a task involving transitivity of lengthequality also failed on a task involving transitivity of length-inequality. In the inequality tasks, a child was shown three sticks, with their tops hidden, and told, for example, that the red one was longer than the blue one, and the blue one was longer than the green one. He was then asked whether the red one was longer than the green one. In the length-equality task, he was told that the pairs of length were equal. Like other components, the strategy of making transitive inferences may be transferred from one concept to another, in this case from inference of equality to inequality (or the reverse). An important step in the development of logical thought is the use of hypothetical thinking, which first occurs with the period of formal operations. The formal-operational child is capable of assuming some proposition to be true, and reasoning as if it were, while at the same time suspending judgment about the actual truth of the proposition. Rather than categorizing statements as ‘true’, ‘false’ or ‘indeterminate’ as a younger child might, the formal-operational child now has a richer inventory of concepts for categorizing statements or thoughts. This inventory parallels the achievement of concrete operations in developing an inventory of physical comparative concepts besides ‘bigger’, ‘smaller’ and ‘same’. It is through the use of this richer inventory of concepts for categorizing propositions that the formal operational child gives the impression of being more ‘reflective’, ‘introspective’ and ‘analytical’ in his reasoning. An example of such a new concept is the finding of Osherson and Markman (1973) that pre-adolescents are generally unable to classify statements as tautologically true or false, even though they can classify statements of similar logical form as true or false empirically. For example, a child will consider thesentence, ‘Either this chip (concealed) in my hand is green or it is not green’, as indeterminate. Hypothetical thinking should thus be seen as an example of an enriched set of strategies for ‘thinking about thinking’, for categorizing self-generated propositions. Other categorizations of propositions which seem likely to be learned after the onset of formal operations are ‘true by definition’, ‘true given some assumption’, ‘analytic’,

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etc. Failure of some of the subplans used in ‘synthetic’, ‘valid as an explanation’, this kind of thought might be responsible for some of the college students’ errors shown in Table 1, as well as for actual errors of inference.

3. Moral Concepts A final area where component theory may be applied is that of moral reasoning. Kohlberg (e.g., 1969, 1971) has thoroughly analysed the development of such reasoning in subjects’ responses to moral dilemmas. He has interpreted this development in terms of a sequence of six stages: In stages 1 and 2, judgments are made on the basis of self-interest of the party in the dilemma who is faced with the decision; in stages 3 and 4, judgments are made according to societal conventions; in stages 5 and 6, principles which do not depend on social convention are used. According to component theory, discrete stages would not be found were it not for the use of a domain in which a small number of components are involved in many strategies of thought, and in the principles applied habitually by an individual. Some of the components required for the transition to stage 2 thought are the subplans required for taking the perspective of someone else when that perspective might differ from one’s own. Such a deficit is reflected in various manifestations of ‘egocentrism’ as shown, for example, by the young child’s inability to choose a picture of a scene that would correspond to someone else’s perception of it, or by the inability to take the listener’s lack of knowledge into account in explaining how to do something. One consequence of this deficit might be the inability to make certain judgments when these judgments depend upon the perspective of some individual; for example, judgments of whether something is ‘annoying’ or ‘pretty’, as opposed to ‘wet’ or ‘hot’, depend upon the tastes of the person making the judgment. The young child is able to make only objective judgments. Thus, a person in stage 1 might say it is worse to steal a lot of worthless junk that nobody wants than to steal a small, but treasured, possession. Here, judgment is made in terms of physical concepts only; subjective concepts are not used at all in evaluating action. Likewise, in stage I, the value of human life is determined by such qualities as the size of a person’s house; in stage 2, the subjective value of a person to others determines the value of his life. Acquisition of a ‘moral’ component may be required for the transition to stage 3 (see Hare, 1952, Ch. 9). This component distinguishes moral judgments such as ‘virtuous’ and ‘evil’ from nonmoral value judgments such as ‘seaworthy’ and ‘pleasant’. (Many terms may be used in both moral and nonmoral senses. Only the moral sense would fit in a frame such as, ‘John blamed [praised] him for being .) Moral

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Jonathan Baron

judgments differ from other judgments in that they imply standards on which groups of people must come to agreement (Hare, 1952). When asked whether a given act is right, a stage 2 person will usually answer as if he had been asked whether the act was in the interest of the person responsible for it. In a situation of conflict, the ‘right’ resolution for one person will be different from that for another. In stage 3, conventional moral judgments may be based on a concept of virtue which may be separated from subjective or physical consequences to the person judged, and which may be endorsed by some community. The subplan required for this advance may thus be the evaluation of a situation from several perspectives at once. (Kohlberg might agree that this skill is crucial, but he would regard it as embedded in a broad structure of other skills; component theory would not.) Evaluation from the perspective of an abstract impersonal code, such as the law or a religion, may characterize a component required for stage 4. Such a component may also be required for application of terms like ‘guilty’, ‘innocent’, ‘legal’, ‘homicide’ and ‘criminal’ in their strictly legal sense. While stage 3 components based on shared personal values may be more salient in most children’s environments, component theory, unlike stage theory, would not necessarily predict that the stage 3 components had to be acquired before the stage 4 ones. The transition to stage 5 requires several strategies used in the construction and evaluation of moral principles; at this point the individual cannot depend uncritically on social convention. One component that is clearly required is the ability, described above, to tag one’s thoughts as ‘hypothetical’. Others may be the ability to generate a hypothetical principle that would account for particular belief, the ability to generate other consequences that are logically consistent with such a principle, and some strategy for evaluating the consequence of an hypothetical principle in order to decide whether to retain it. This evaluation strategy might involve deciding whether the consequence would be acceptable to some group of people, possibly (in stage 6) all present and future people. Similar strategies might be involved in moral argument. In trying to persuade someone else, one strategy is finding a principle that would account for many of their beliefs as well as yours, generating consequences from it to get them to accept the principle, and finally showing them that it is inconsistent with their original stand in the argument. Again, while it is easy to see how the complexity of habitual strategies like these could retard their acquisition, there is no theoretical reason why many components of these strategies could not be acquired before components which characterize earlier stages. Further, some of the components used in moral reasoning are specific to this area, such as the ‘evaluation strategy’, so we need not expect a close correspondence between moral development and development of other areas which use different components, such as (possibly) mathematical reasoning.

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4. Comparison with other theories In conclusion, I shall review the relation of component theory to other traditions which try to account for similar ranges of phenomena. In this way, the potential contribution of component theory to psychology and education may be made clear. The major theory which attempts to account for the range of phenomena described here is that of Piaget (1970; see also Flavell, 1970). The essential features of his theory have been incorporated into other theories of particular domains, such as those of Kohlberg (1971) and Perry (1970). Several features of Piaget’s theory are incorporated into component theory as well. Component-theory can be seen as a simple extension of Piaget’s notion of assimilation and some of Jakobson’s (1942) ideas about the development of differentiation, Our assumption that the marked form (with the required component) is replaced by the unmarked (primitive concept) before the former is learned parallels Piaget’s notion of assimilation of novel situations to old schemes. The only difference is that component theory assumes that the scheme (strategy) often ‘accommodates’ by mere addition of new components. A second point of agreement with Piaget’s theory is the notion of horizontal decalage. This is parallel to our assumption that learning a component of one concept does not automatically bring about the attachment of that component to other concepts but rather facilitates such attachment when future opportunities for learning arise (giving rise to the appearance of stages in limited domains). For Piaget, the onset of a new stage is not shown simultaneously in all manifestations of that stage but rather in an increased readiness to acquire such manifestations. There is one major point of difference between component theory and Piagetian theory. This difference concerns the ideas of equilibrium, stage and structure, which are, for Piaget and his followers, closely interrelated. According to these ideas, certain acquisitions (of concept, components, strategies or whatever) are interrelated so as to form a stable, ‘equilibrated’, whole if they are all present. For example, there is held to be a sense in which understanding of commutativity, associativity and identity axioms in algebra ‘hang together’. While it is possible to understand the implications of one without understanding those of the others, such incomplete understanding is unstable. For Piaget, such a set of interrelated acquisitions is said to constitute a structure. There are several alternative, more-or-less all-inclusive, structures, and these structures may be ordered developmentally into stages. Component theory makes no assumption about structures. This question, of course, will not be resolved easily (see Flavell, 1971). Yet there may be some value in a developmental theory which is Piagetian in spirit but without the assumption of stages and structures. Much modern educational theory and practice incorporates the idea of unified stages implicitly. Thus, we often rationalize teaching a certain

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subject matter by saying that its study brings about ‘general intellectual development’. If intellectual development does not occur in general, but rather in isolated areas, independently of other areas, such teaching may bring about development only with respect to the concepts and components of the matter in question. For example, there seems to be little reason for acquisition of length, speed and number concepts to facilitate acquisition of mature moral judgment. Thus, while component theory may be difficult to compare empirically with Piagetian stage theory, its different consequences in education suggest that it is at least worth considering as a possible alternative. Another theoretical tradition which has concerned itself with some of the issues discussed here is learning theory, particularly as developed by GagnC (1968) and Furby (1972). In many ways their approach is similar to that of component theory. The acquisition of conservation, for example, is explained in terms of acquisition of subordinate pieces of knowledge such as the knowledge that equivalence is transitive. This sort of learning theory is entirely consistent with component theory and differs only in emphasis; where Gag&s learning theory concerns itself with behavioral tests of what is known, research based on component theory concerns itself with the strategy used to apply the knowledge. Another difference is that where Gagne emphasizes transfer from simple knowledge to more complex knowledge which relies on the simple knowledge, component theory also emphasizes transfer of components from one concept to another. For Gag& the goal of education seems to be to teach certain specific complex concepts; component theory, on the other hand, is also consistent with the goal of providing a base of components so that future learning will be facilitated even if the specific content of that learning is largely unknown. A number of other theories (McLaughlin, 1963; Pascual-Leone, 1970; Klahr and Wallace, 1970) have attempted to account for conceptual development in terms of various capacities that increase with age such as memory span, ‘central computing space’ or ‘drive’. These theories may deal adequately with deficits in which certain tasks cannot be done at all, such as responding to several stimuli at once or carrying out a complex plan. But their extension to tasks in which errors are systematic, and characterized by assimilation of one concept to another, has been very limited so far. It is not clear what additional assumptions would be required for such extensions besides those made by component theory. Surely, even the most ardent componenttheorist must admit that capacity frequently limits performance, and that it increases with age. He must also admit that acquisition of some components is limited by the capacity to carry out complex strategies. But he need not admit that the growth of capacity is a sufficient principle to explain the pattern of development.

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REFERENCES Arch, S. E., and Nerlove, H. (1960) The development of double function terms in children: An exploratory study. In B. Kaplan and S. Wapner (Eds.), Perspectives in psychological Heinz Werner,

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Universities Press. Baron, J. (1973) Effect of inconsistent distinctiveness of artificial semantic features on retrieval speed. Manuscript. -and Kaiser, A. (1973) Semantic components in children’s acquisition of pronouns. Draft. and Kaiser, A. (in preparation) A semantics-based description of a child’s early sentences. Bennett, D. (1969) A stratificational view of polysemy. Linguistic Automation Project Report. New Haven, Yale University. Bierwisch, M. (1967) Some semantic universals of German adjectivals. Found. Lang., 3,

Clark, H. H. (1970) The primitive nature of children’s relational concepts: A discussion of Donaldson and Wales. In J. R. Hayes (Ed.), Cognition and the development of language. New York, Wiley. Donaldson, M., and Balfour, G. (1968) Less is more: A study of language comprehension in children. Brit. J. Psychol., 59, 461-472. and Wales, R. J. (1970) On the acquisition of some relation terms. In J. R. Hayes (Ed.), Cognition and the development of Language, New York, Wiley. Ervin-Tripp, S. M., and Foster, G. (1960) The development of meaning in children’s descriptive terms. J. abn. sot. Psychol., 61, 271-275.

Flavell,

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Brown, R., Cazden, C. B., and Bellugi, U. (1969) The child’s grammar from I to III. In J. P. Hill (Ed.), Minnesota symposium on child psychology, Minneapolis, University of Minnesota Press. Bruner, J. S., Goodnow, J. J., and Austin, G. A. (1956) A study of thinking. New York, Wiley. and Kenney, H. J. (1966) On relational concepts. In J. S. Bruner, R. R. Oliver and P. M. Greenfield (Eds.), Studies in cognitive growth. New York, Wiley. Chafe, W. L. (1970) Meaning and the structure of language. Chicago, University of Chicago Press. Chomsky, N. (1965) Aspects of the theory of syntax. Cambridge, M.I.T. Press. Clark, E. V. (1971) On the acquisition of the meaning of before and after, J. verb. Learn. verb. Beh., 10, 266-275. (1973) What’s in a word? On the child’s acquisition of semantics in his first language. In T. E. Moore (Ed.), Cognitive development guage. New

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(1963) The developmental of Jean Piaget. Princeton, N.J.,

Van Nostrand. (1970) Concept development. In P. H. Mussen (Ed.). Carmichael’s manual of childpsychology. New York, Wiley. (1971) Stage-related properties of cognitive development. Cog. Psychol., 2, 421450.

Furby, L. (1972) Cumulative learning and cognitive development. Hum. Devel., 15, 265-286. Gag&, R. M. (1968) Contributions of learning to human development. Psycho/. Rev., 75, 177-191.

Gelman, R. (1969) Conservation acquisition: A problem of learning to attend to relevant attributes. J. exp. child Psychol., 7, 167-187.

Goodenough, W. (1956) Componential analysis and the study of meaning. Language, 32, 195-216.

Greenberg, J. H. (1966) Language universals. In T. A. Sebeok (Ed.), Current trends in linguistics, III, 61-112, The Hague, Mouton. Hare (1952) The language of morals. London, Clarendon Press. Haviland, S. E., and Clark, E. V. (in press) ‘This man’s father is my fathers son’: A study of the acquisition of English Kin terms. Paper presented at Conference on Kinship Semantics, Riverside, California, To appear in the Proceedings, edited by

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H. Gladwin and D. B. Kroenfeld (1972). Ingram, D. (1971) Transitivity in child language. Language, 47, 888-910. Jakobson, R. (1942) Child language, aphasia and phonological universals, (A. Keiler, trans.). The Hague, Mouton, 1968. Kahneman, D., and Tversky, A. (1972) Subjective probability: A judgment of representativeness. Cog. Psychol. 3,430-454. Katz, J. J., and Fodor, J. A. (1963) The structure of a semantic theory. Language, 39, 170-2 10. Klahr, D., and Wallace, J. G. (1970) An information processing analysis of some Piagetian experimental tasks. cog. Psycho/., 1, 358-387. Kohlberg, L. (1969) Stage and sequence: The cognitive-developmental approach to socialization. In D. Goslin (Ed.), Handbook of socialization theory and research. New York, Rand McNally.

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(1971) From is to ought: How to commit the naturalistic fallacy and get away with it in the study of moral development. In T. Mischel (Ed.), Cognitive development and epistemology. New York, Academic Press. Lamb, S. M. (1964) The semenic approach to structural semantics. Amer. Anth., 66 (3), Part 2, 57-78. Lawson, G., Baron, J., and Siegel, L. S. (in press) The role of length and number cues in children’s quantitative judgments. Child Dev.

Lewis, M. M. (1963) Language, thought and personality, New York, Basic Books. McLaughlin, G. H. (1963) Psycho-logic: A possible alternative to Piaget’s formulations. &-it. J. educ. PsychoI., 33, 61-67. McNeill, D. (1970) The development of language. In P. Mussen (Ed.), Charmichael’s manual of child psychology. New York, Wiley. Mehler, J., and Bever, T. G. (1967) Cognitive capacity of very young children. Science, 153, 141-142. Menyuk, P. (1969) Sentences children use. Cambridge, M.I.T. Press.

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and Markman, E. (1973) Language and the ability to evaluate contradictions and tautologies. Draft, University of Pennsylvania. Pascual-Leone, J. (1970) A mathematical model for the transition rule in Piaget’s developmental stages. Acta Psych., 32, 301-34s.

Perry,

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and Winston. Piaget, J. (1970) Piaget’s theory. In P. H. Mussen (Ed.), Carmichael’s marzual of child psychology. New York, Wiley. Reich, P. A., Rice, K., and Schneider, J. (1972) The acquisition of a semantic rule. Unpublished draft. Saltz, E., Soller, E., and Sigel, I. E. (1972) The development of natural language concepts. Child Devel. 43, 1191-1202. Schlesinger, I. M. (1971) Production of utterances and language acquisition. In D. Slobin (Ed.), The ontogenesis of language:

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Trabasso, T., Rollins, H., and Shaughnessy, E. (1971) Storage and verification stages in processing concepts. Cog. Psychol.. 2, 239-289.

Semuntic components and conceptual development

On peut rendre compte, par une thtorie d’acquisition par addition successive de composants, d’un certain nombre de phenombnes d’apprentissage du sens des mots. Le mecanisme serait analogue a celui propose pour le developpement phonologique. Si I’on definit un concept comme une composition habituelle et un composant comme un element de composition, on peut Btendre cette theorie a I’acquisition des concepts en

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general. En effet elle rend compte du developpement des concepts logiques, des raisonnements physiques ou moraux aussi bien que des concepts verbaux. Le principe d’une acquisition composant par composant inclut un transfert possible d’apprentissage entre les concepts partageant les memes composants et peut se poser en concurrence des theories du developpement par stades.

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Semantic

heuristics

and syntactic

analysis*

KENNETH I. FORSTER ILMAR OLBREI Monash University

Abstract This paper investigates the hypothesis that the component of sentence processing time directly attributable to syntactic processing depends critically on certain semantic properties of the sentence. Using two different procedures, it is found in a series of experiments that there is little evidence to support this view. Speci&cally, it is shown that syntactic processing time tends to be constant for sentences of varying semantic plausibility but constant syntactic structure, andfurther, that reversibility fails to aflect sentence processing in a systematic way. These facts are interpreted as indicating that the recovery of the underlying structure of a sentence is controlled by purely syntactic properties of the input. In order to provide an account of how a speaker of a language understands a sentence, one must come to terms with the fact that sentence comprehension is not a unitary process. The act of understanding a sentence involves decision-making at three levels of analysis, the lexical, syntactic and semantic levels, and it is generally assumed that there is considerable interaction between processing at any one level and processing at other levels. This assumption of interaction between levels greatly complicates the task of making inferences from experimental data, since we are unable to study the variables that control processing time at one level without also having to consider the effects of the same variables at other levels. Special problems arise in the case of experiments designed to study semantic processing. The appropriate experimental design holds syntactic structure constant and * This research was supported by a grant to the first author from the Australian Research Grants Committee. Requests for reprints should be addressed to K. I. Forster, Department of Psychology, Monash University, Clay-

ton, Victoria, Australia 3168. The authors wish to thank Donald Thomson and Ivan Watson for reading earlier versions of this paper.

Cognition 2(3),

319-347

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studies the covariation of meaning and sentence processing time. However, this design assumes that there will be little or no variation in lexical or syntactic processing time as a function of meaning. The latter assumption seems untenable, especially in view of the widespread belief that the sequence of operations necessary to analyze the syntactic structure of a sentence can be drastically modified by certain semantic properties of the sentence (e.g., Slobin, 1966; Schlesinger, 1968; Bever, 1970; Schank, 1972). The purpose of this paper is to re-examine this belief and to present evidence from several experiments that bear on the issue. It will be argued that the current view of sentence processing is unnecessarily complex, and that there are grounds for making the simplifying assumption that syntactic processing is relatively independent of semantic processing, in the sense that the time required to analyze the syntactic structure of a sentence is constant, despite variations in the meaning of the sentence. Before outlining the experiments, it is necessary to at least sketch a preliminary model of sentence processing, indicating clearly the possible sources of interaction. As indicated above, we assume three levels of processing: Lexical, syntactic and semantic. Lexical processing refers to the processes of word recognition and lexical access (e.g., Oldfield, 1966; Rubenstein, Garfield and Miilikan, 1970; G,>ugh, 1972; Meyer and Schvaneveldt, 1971). The purpose of lexical processing is to gain access to the information contained in the mental lexicon about each lexical item in the sentence and involves a search through the lexical entries until a match is obtained between the perceived features of a segment of the input and the features contained in a lexical entry. Syntactic processing refers simply to the formulation and testing of hypotheses about the grammatical relations that hold between the lexical items, while semantic processing refers to the formulation and testing of hypotheses about the meaning of the sentence. In the simplest case, we would assume that hypotheses about the syntactic structure are based exclusively on syntactic cues. These cues would consist of items of information such as the distribution of inflections, the surface order of formatives, the placement of relative pronouns (e.g., Fodor and Garrett, 1967) and the syntactic features of the lexical items provided by the lexicon (e.g., Fodor, Garrett and Bever, 1968). However, we must acknowledge the possibility that syntactic hypotheses might also be based on semantic cues, and here we would include the semantic features of the lexical items provided in the lexicon (e.g., selection constraints) and also purely pragmatic features derived from the speaker’s knowledge of the real world, such as the knowledge that dogs seldom wear golf-shoes or that firemen are typically employed to put out fires. Although there are bound to be areas of overlap between syntactic and semantic cues, this problem can be sidestepped by considering only relatively clear cases. Ideally, we would also wish to assume that syntactic hypotheses are tested by determining whether they are consistent only with the syntactic properties of the

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sentence, but again, the possibility of interaction cannot be overlooked. Once formulated, a syntactic hypothesis may be evaluated by determining whether it is consistent with current semantic hypotheses. We shall return to this problem later. Finally, it should be noted that these proposals are not meant to imply that processing at any one level must be completed before processing at any other level can commence. Instead, processing may proceed at all three levels simultaneously, with syntactic and semantic hypotheses being constructed on the basis of quite independent cues. The most important consequence of this assumption is that the total time for sentence comprehension is not a simple sum of the times required for processing at each level. In Figure 1, the main information channels in the model are summarised and labelled. Channels A and B refer to the transfer of lexical information to higher levels, the former channel involving only syntactic features, and the latter involving semantic and pragmatic features. Channels D and E refer to feedback to the lexical processor Figure 1. The six possible information channels between the three levels of processing

LEXICAL

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E

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from the syntactic and semantic processors, which allows for the possibility that lexical search will be facilitated if the syntactic or semantic context of a given lexical item is known. Channels B and C represent the input to the semantic processor. The information in channel C stems from the syntactic processor and consists of a statement of the grammatical relations that have been isolated. Thus, hypotheses about the meaning of the sentence are based in part on a knowledge of grammatical relations, which are transferred piecemeal, as they are recovered. However, semantic hypotheses may also be based on purely lexical information (channel B). That is, in the sentence The doctor cured the patient, the semantic processor may be able to correctly predict the meaning of the sentence purely on the basis of the pragmatic information available about the key lexical items doctor, cure and patient. It is assumed that such hypotheses could be constructed quite independently of syntactic processing, and indeed, in some circumstances, these hypotheses may be accepted without checking that they are consistent with the known grammatical properties. Of central importance in this paper is the remaining channel F, which represents feedback to the syntactic processor from the semantic processor. In this else, information from the semantic level is used in a heuristic fashion to modify syntactic processing. This could occur in two ways. To take the example cited above, when the semantic hypothesis about the meaning of the sentence is formulated on the basis of pragmatic cues, certain predictions about the correct syntactic analysis may be formulated and relayed back to the syntactic processor. For example, it may be hypothesized that doctor must be the logical subject of cure, and the syntactic processor may merely have to determine whether this is a possible analysis. This may well prove to be a more rapid method of determining syntactic structure than just relying on purely syntactic cues. That is, the analysis of structural relations is facilitated by considering the likely meaning of the sentence, in this case, owing to the fact that the correct analysis has been suggested by semantic hypotheses. Alternatively, discovery of the correct syntactic analysis may be facilitated by a more rapid elimination of incorrect syntactic hypotheses. Thus, the syntactic hypothesis that doctor is the object of cure (induced, say, on some purely syntactic cue) could be rejected immediately by noting that it is incompatible with the current semantic hypothesis. Obviously, there wouid !rave to be some procedure for weighting hypotheses derived from different sources of evidence, so that decisions could be made when conflicts arise. In what follows, the primary question of interest is whether channel F plays a significant role in sentence processing. Two positions on this issue can be contrasted. The first, which will be referred to as the constancy hypothesis, asserts that channel F is effectively inoperative, and that the component of total processing time directly attributable to syntactic processing remains constant despite variations in meaning.

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The alternative view, which will be referred to as the interactive hypothesis, asserts that evidence from the semantic level of processing plays an important heuristic role in syntactic decision making, and hence it should be possible to show that the syntactic component of total processing time is markedly affected by semantic properties of the sentence. The major assumptions of the constancy hypothesis are as follows: (i) That the only inputs to the syntactic processor are the syntactic properties of the lexical items provided by the lexicon (channel A), and the cues available from the positioning of formatives in the input string; (ii) that decisions about syntactic analysis are made without reference to the possible meaning of the sentence; (iii) that although semantic hypotheses may be formulated on the basis of lexical information (channel B) while syntactic processing is still in progress, the only function of these hypotheses is to expedite semantic interpretation when the syntactic analysis becomes available; and (iv) that semantic processing is not completed until the syntactic analysis is available, and that semantic hypotheses must at least be checked for compatibility with the syntactic analysis. The major assumptions of the interactive hypothesis, on the other hand, can be represented as the denial of assumptions (i) - (iii), with an indeterminate position on assumption (iv). We are now in a position to interpret the evidence which bears on these issues. The most frequently cited evidence for the interactive view comes from the reversibility phenomenon (Slobin, 1966). When selection constraints dictate the assignment of the key lexical items in the sentence to the functions of logical subject or object (e.g., The girl is watering theflowers), the sentence is said to be nonreversible. When there are no such constraints (e.g., Thegirl is watching the dog), the sentence is said to be reversible. Generally, nonreversible sentences are processed more rapidly than reversible sentences. This result establishes that reversibility affects part of the total process, without necessarily supporting the interactive position. That is, it could be that reversibility affects the time required to determine the meaning, not the structure, of the sentence. However, Slobin also showed that the usual difference in the time required to process actives and passives was absent for nonreversible sentences; passives took longer to process than actives only when there were no semantic cues. On the assumption that the active-passive difference reflects syntactic complexity, it is clear that this result supports the interactive position. Much the same result has been obtained for pragmatic cues (Herriot, 1969). In this case, nonreversibility is produced by expectancies about the probable meaning of the sentence. In nonreversible sentences, there are strong expectancies that constrain the assignment of nouns to grammatical functions (e.g., The doctor cured the patient), whereas in reversible sentences, these are absent (e.g., The boy spoke to the teacher). Once again, the active-passive difference was obtained only for reversible sentences.

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The same model accounts for both results. The problem set for the syntactic analyzer is to decide whether the sequence NP, . . . V . . . NP, should be analyzed as an active or a passive sentence. For nonreversible sentences, a semantic test can resolve the issue immediately, whether we are dealing with logical reversibility (Slobin) or pragmatic reversibility (Herriot). In the first case, the incorrect hypothesis leads to an anomalous sentence, and in the second, it leads to an implausible sentence, and hence the hypothesis can be immediately rejected. However, the semantic test is of no assistance for reversible sentences, and further syntactic processing is required. Evidence for the constancy hypothesis has been provided by Forster and Ryder (1971) in an experiment with similar logic to the reversibility experiments, except that semantic properties were manipulated in a different way. The general design of experiments of this type is as follows: The relative difficulty of N sentence types, T,, Tz, . . .. TN is measured under M semantic conditions, S,, S, . . . . SM, where a given sentence represents a combination of a particular sentence type and semantic condition S, (Ti). In the reversibility experiment, there are two sentence types (active and passive), and two semantic conditions (reversible and nonreversible). If it can be shown that the relative difficulty of the N sentence types varies markedly as a function of the semantic condition, then this constitutes support for the interactive hypothesis. In the Forster and Ryder (1971) experiment, twenty different sentence types were studied under three different semantic conditions: (1) Where the meanings of the sentences were entirely plausible and relatively predictable from the meanings of the key lexical items (e.g., The queen danced at the ambassador’s ball); (2) where the meanings were relatively implausible (e.g., The author stared at his neighbour’s elbow), and it would be expected that semantic hypotheses based on lexical information would be less informative, and (3) where the sentences were semantically anomalous (e.g., The hotel arrived at the government’s

bark).

In the first condition, syntactic analysis would be aided by the fact that the most likely semantic organization correctly predicts the appropriate syntactic analysis. However, in the second condition, the events referred to in the sentence were deliberately chosen to be relatively bizarre or unexpected. Knowing the meaning of the lexical items does not immediately suggest the correct syntactic analysis, and if syntactic hypotheses are sometimes rejected because they lead to implausible meanings, then it follows that at some stage, the correct syntactic hypothesis will initially be discarded, presumably to be later reinstated. Finally, in the third condition, where the sentences were semantically anomalous, it is obvious that semantic heuristics would be of no assistance whatever to the syntactic processor. These facts suggest that the time required to syntactically analyze the same structures under these three different semantic conditions would vary considerably. Within any one of these conditions, the relative difficulty of the twenty structures

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would be a function of the time required to identify the structure of the sentence, and also the time required to determine the meaning (although these times are not necessarily additive). Since the meanings varied, any correlation between the three sets of estimates of processing difficulty would indicate a relatively constant effect of syntactic structure on processing time. The results obtained by Forster and Ryder (1971) showed clearly that the effects of syntactic structure on processing complexity were positively correlated across the three semantic conditions, despite the very considerable effects of implausibility and anomaly on overall performance. This result suggests that semantically based heuristics do not exert a profound effect on syntactic processing. However, the existence of a positive correlation due to structure does not rule out the interactive hypothesis, nor does it do more than provide the minimal support necessary for the constancy hypothesis to be true. That is, a positive correlation is a necessary condition for the constancy hypothesis to be true, but is by no means a sufficient condition. Thus we arrive at the point of central concern in this paper. Given the very strong apparent effect of semantic factors on syntactic processing observed by Slobin (1966), it would be expected that in the Forster and Ryder (1971) study it would be quite difficult to demonstrate a positive correlation due to syntactic structure. The latter study tends to support the constancy hypothesis, whereas the former disconfirms it. If both results prove to be empirically reliable, then it must be concluded that the interpretations we have offered are incorrect. The aim of the experiments to be reported in this paper was to determine whether both of these effects were sufficiently robust to be detectable under a new set of experimental conditions. The experimental technique chosen was an extension of the decision latency procedure used by Rubenstein, Garfield and Millikan (1970) to study word recognition. Their task required the subject to decide whether a given sequence of letters formed a word or not. This procedure can easily be extended to sentences: The subject is asked to decide whether a given sequence of words forms a meaningful sentence or not. Presumably, the only way such a decision can be made is to attempt to analyze the sequence as a meaningful sentence in English. Hence, decision times should reflect the total processing time required for the sentence. This technique has been used previously with some degree of success to study context effects (Dooling, 1972). In the first experiment, the constancy effect is re-examined using the decision latency technique, and the same procedure is then used in the next three experiments to study the reversibility phenomenon. Experiment 5 also examines reversibility, using the rapid visual presentation technique originally used in the Forster and Ryder (1971) study.

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Experiment 1 The purpose of this experiment was to determine whether the syntactic constancy effects observed by Forster and Ryder (1971) can also be obtained with a decision latency technique. The design involves comparing the distributions of latencies of two sets of twenty sentences matched for syntactic structure, one set having plausible meanings and the other implausible meanings. The anomalous sentences used by Forster and Ryder (1971) could not be used in this design, since preliminary testing revealed that these sentences were almost always rejected by subjects, and hence that decision latency does not really reflect the total time required to analyze the structure and ‘meaning’ of these sentences. The specific prediction tested was that there would be a positive correlation between the processing times for plausible and implausible sentences of the same syntactic structure. In addition, a number of subsidiary hypotheses were considered. These were mainly concerned with the adequacy of the decision latency technique itself. Thus, regardless of the outcome of the first hypothesis, it should be the case that implausible sentences are associated with longer decision latencies than plausible sentences. In addition, it was expected that two-clause sentences would produce longer latencies than one-clause sentences of the same length. Method The sentences were taken from Forster and Ryder (1971). Twenty different surface structures were used, half consisting of one clause and half consisting of two clauses. On the basis of previous findings (Forster, 1970; Forster and Ryder, 1971) it was expected that the two-clause sentences would take longer to process than the oneclause sentences, although recent evidence (Holmes and Forster, 1972) suggests that this is not necessarily true for all two-clause constructions. Two versions of each surface structure were prepared, one having a plausible meaning, and one having a relatively unexpected, or implausible, meaning. The actual sentences used are listed in the Appendix. All sentences contained seven words, and the average word length was equated for all four types of sentences. In addition, twenty ungrammatical sequences were included. These were not simple random word sequences, since this would enable a correct discrimination of sentences. and non-sentences to be based on an analysis of only the first two or three words in the sequence. To prevent this, the ungrammatical sequences were designed so that, superficially at least, they resembled grammatical sequences. Examples of these items are: Some of the oldest six down stooping. About seven of nothing in the night.

Semantic

The unbearable lightness such of running The chorus of winning loud the lions.

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quiet.

Slides were prepared in such a fashion that when projected, the sentence was displayed as it would appear in a normal typewritten text, except that the lettering was white on a dark background. The initial letter of the first word of all sequences was in upper case. The subjects were instructed that their task was to determine as quickly as possible whether the presented sequence was an intelligible, grammatical sentence. If the sequence was a sentence, the subjects responded by pressing a push-button held in the right hand, but if it was not, no response was required at all. This arrangement was designed to simplify the response conditions as much as possible. Reaction times were measured from the onset of the test slide to the subject’s response. On those trials in which the subject failed to respond, the experimenter waited for ten sets before terminating the trial. The action of the slide projector in changing slides served as a warning signal for the beginning of each new trial. The instructions provided clear examples of the types of items used, and the subjects were warned that some of the sentences would have unexpected meanings. It was also explained that the ungrammatical sequences would obviously be ungrammatical, and examples were given. Eight practice items were included to familiarize the subject with the procedure and materials. All subjects were tested individually, and a different random ordering of items was used for each subject. Ten undergraduate and postgraduate volunteers served as subjects. They were paid for their participation in the experiment. Results The principal analysis of the data concerned the hypothesis that there would be a positive correlation between decision latencies for the plausible and implausible versions of the twenty surface structures used in the experiment. In order to test this hypothesis, mean latencies were computed for each of the 40 sentences, averaging over the 10 subjects. Two sets of item means were computed. For the first set, in order to eliminate the distortion introduced by exceptionally long latencies, the data for each individual subject were analyzed, and cutoff points were set two standard deviation units above and below the mean for each subject. Any observations exceeding these cutoffs were replaced by the appropriate cutoff value. These adjusted scores were then used to determine means for each item. For the second set of means, the reciprocals of the unadjusted raw observations for each subject were used. This transformation also limits the bias introduced by unduly long latencies and serves as a check on the first analysis. In both analyses, errors were excluded altogether. For both sets of data, there was a significant positive correlation between the means

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for the plausible sentences and the means fo: the corresponding implausible sentences. The obtained product-moment correlations were .582 (y < .Ol) for the means based on the adjusted latencies, and .655 (p < .Ol) for the means based on the reciprocals. These results confirm the findings of Forster and Ryder (1971), and the obtained values are comparable to the value of .65 reported in the earlier study. Subsequent analysis of the results investigated whether decision times also reflected the number of clauses in the sentence, and the plausibility of the meaning. Means for each of the four conditions were computed for each subject, and these were analyzed as a 2 x 2 factorial with repeated measures on each factor. To ensure that the results were independent of the data metric chosen, analyses were carried out separately for the adjusted latencies, and for the reciprocals. Table 1 shows the means for the four conditions, using the adjusted latencies. As expected, two-clause sentences took longer to process than one-clause sentences of the same length F(1,9) = 52.09, p < .Ol, and this effect was also observed in the reciprocal analysis. Also, implausible sentences took longer to process than plausible sentences, F(1,9) = 46.99, p < .Ol, with a similar effect for reciprocals. As can be seen in Table 1, the effect of adding an extra clause was not entirely constant. When an extra clause was added to a plausible sentence, decision times were increased by 252 msec, but in an implausible sentence, the extra clause added 364 msec to processing time. However, in this case, there was disagreement between the two analyses; for the adjusted latencies, the interaction of number of clauses and plausibility was not significant, F(1,9) = 3.43, p > .05, but in the reciprocal analysis it was significant, F(1,9) = 5.19, p < .05. Table

1.

Mean adjusted latencies (in msec) as a function of number of clauses and plausibility in Experiment 1

Plausible

Implausible

One-clause Two-clause

1281 1533

1547 1911

Difference

252

364

In studies of this kind, where variation between sentences is almost as great as variation between subjects, it is important to check that the effects are typical of all items. The appropriate analysis for this purpose is one which takes the means for individual items (sentences) as the basic data, not the means for each subject. In this case, the subject factor is collapsed, and the design becomes a straightforward factorial with a within-cells error estimate and no repeated measures. Under these conditions, a significant effect can only be obtained when the majority of items show the same

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effect. This is not necessarily true of the subject analysis, where a small minority of items can produce a consistent effect for each subject. Accordingly, the item means were analyzed, and again, two analyses were carried out, one on the adjusted latencies and one on the reciprocals. For the adjusted latencies, both the number of clauses and plausibility produced significant results, F(1,36) = 12.96, p < .Ol and F(1,36) = 12.34, p < .Ol, but the interaction term was not significant, F(1,36) = 0.40, p > .05. The reciprocal an.alysis showed exactly the same pattern. Thus it can be concluded that the main elfects were general effects observed for all items, but that the interaction previously observed in the subject analysis was not typical of all items.

Discussion The results of this experiment, taken together with the results of Forster and Ryder (1971), provide strong evidence that the time required to analyze a particular syntactic structure is approximately constant, despite gross variations in the plausibility and well-formedness of the meaning assigned to that structure. Such a result lends little support to an interactive view which argues that syntactic analysis is normally guided by semantic cues, although this hypothesis is by no means invalidated. The results obtained with the decision latency technique also confirm other findings. First, in agreement with earlier studies using accuracy of report as a criterion of performance (Forster, 1970; Forster and Ryder, 1971), two-clause sentences produced longer decision times than one-clause sentences of the same length, implying that in some sense, the clause constitutes a major unit of processing. In addition, semantically implausible sentences took longer to process than plausible sentences, a finding which is consistent with results obtained with a variety of techniques (Rosenberg and Jarvella, 1970; Herriot, 1969; Forster and Ryder, 1971). This is a particularly important result, since the decision latency technique is not open to some of the criticisms that could be levelled against earlier studies demonstrating the same effect. In particular, it cannot be argued that performance on plausible sentences is superior merely because subjects are better able to reconstruct the input sentence, a criticism which applies only to techniques requiring subjects to actually report the sentence. As noted earlier, the increment in processing time produced by the embedded clause was not exactly the same for plausible and implausible sentences (252 and 364 msec respectively), aithough this difference was significant in only one of the four separate (but not independent) tests of the interaction term. Although the possible existence of an interaction between number of clauses and plausibility is of some interest, it should be noted that such an effect could be interpreted in a number of ways. For example, it could imply that implausibility increases the time required to

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syntactically process an embedded clause, in which case some doubt would be cast on the constancy hypothesis. But equally, such an interaction might simply mean that the number of clauses affects not only syntactic processing time but also semantic processing time; that is, a two-clause sentence takes longer to process semantically than a one-clause sentence. This is a very real possibility but is in no way inconsistent with the constancy hypothesis. Although we have argued that the results provide support for the principle of constancy of syntactic processing times, it might be claimed that, in fact, the results show the opposite; the reported correlations between processing times for matched structures show that syntactic variables control less than 40% of the total betweensentence variance. This implies that at least 60% of the variance was controlled by non-syntactic variables, which might be taken as evidence that syntactic processing time was I?otconstant across the two semantic conditions. This argument confuses syntactic processing time with total processing time. The constancy hypothesis relates to the former time, not the latter. However, observations can only be made on total processing time, and syntactic processing time is only one component of this, along with semantic processing time, measurement errors, sampling errors, etc. Thus there is an upper limit to the maximum possible effect that could have been observed, and this upper limit would have to be well below 100x, probably nearer to 50 %, since the effect of plausibility (a semantic effect) was roughly equal to the effect of number of clauses (a syntactic effect). The major difficulty here is that we do not know how large a correlation to expect if the constancy hypothesis is true. If highly reliable data were used, and if syntactic processing time could be measured directly, then the correlation should be much higher. But given that neither of these conditions was met, all that can be concluded is that the constancy hypothesis requires a non-zero positive correlation, which in fact was obtained.

Experiments 2-3 In the next experiments, attention is directed to the reversibility phenomenon. As previously argued, this effect can be interpreted as showing that syntactic processing time is not constant when the number of semantic cues to the structure is varied. It should be noted that the reversibility effect is in no way incompatible with the results of the previous experiment. In Experiment 1, it was shown that syntactic processing time tended to be constant for plausible and implausible sentences. But this does not directly imply that it should also be constant for reversible and nonreversible sentences, since plausibility and reversibility are entirely orthogonal attributes. For example,

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implausible sentences can be either nonreversible, as in The JEea jumped over the skyscraper, or reversible, as in The Jlea jumped over the girafse, Thus, empirically, it is entirely possible that both the constancy and reversibility results are correct. The conflict arises only when the implications of these results are considered, since reversible and implausible sentences share the common property of providing fewer semantic cues to structure than non-reversible and plausible sentences, respectively. The aim of these experiments was to determine whether it is possible to reproduce the reversibility phenomenon, using procedures designed to eliminate some of the criticisms that can be made of earlier experiments (Slobin, 1966; Herriot, 1969). The first procedural change involved using the decision latency technique outlined in the previous experiment. We believe this to be a more direct index of sentence processing time than either of the techniques previously used, which at best could only be described as highly indirect. The second procedural change involves the selection of sentences to be used in the experiment. One of the predictions to be made from the interactive theory is that reversible sentences will take longer to process than nonreversible sentences. However, reversible and nonreversible sentences must differ in meaning, and hence they may also differ in plausibility. Given the very strong effects of semantic plausibility on total processing times, it is clearly necessary to ensure that the two kinds of sentences do not differ in plausibility. There is some reason to expect that reversible sentences will often be less plausible than their nonreversible counterparts. Although we have not attempted to give any precise definition of plausibility, it is not too difficult to propose an operational test. For example, consider the procedure used by Rosenberg and Jarvella (1970) to manipulate what they call the semantic integration of a sentence. Sentences were constructed by asking subjects to fill in the blank in sentences such as the following: The dog chased the -. The majority of subjects will give cat as a response, and this fact is taken to mean that the sentence The dog chased the cat is semantically wellintegrated. On the other hand, the fact that none give alligator as a response indicates that the sentence The dog chased the alligator is less well-integrated semantically. This distinction is extremely close, if not identical, to the intuitive distinction between plausible and implausible sentences. If we accept that plausibility can be indexed by the associative predictability of the sentence, then it can easily be seen that this index will not always be the same for reversible and nonreversible sentences. For example, consider some of the sentences used by Herriot (1969) to manipulate pragmatic reversibility. For nonreversible sentences, we have examples such as The doctor cured the patient, where any one of the three lexical items is highly predictable from the other two. For reversible sentences, we have examples such as The army assisted the navy, where associative connections

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would be far weaker. Again, in the case of Slobin (1966), we have as an example of a logically nonreversible sentence, The girl watered thejowers. In this case, predictability is probably very high, although no higher than the example Slobin gives of a reversible sentence, The dog chased the cat (by Herriot’s standards, a nonreversible sentence). But if we chose to compare the nonreversible sentence with the following reversible counterpart, The girl obscured the,flowers, we would obviously be confounding reversibility effects with associative predictability (plausibility) effects. These problems can be minimized by ensuring that both sets of sentences are matched for associative predictability, and hence plausibility. In the experiments to be reported, the samples of items to be used were checked for variations in plausibility in the following way: The sentences were presented in a visually degraded form (blurred typewritten copies) to a panel of colleagues who were given unlimited time to reconstruct as much of the sentence as possible. The more predictable the sentence, the greater the probability that the entire sentence will be reconstructed. Also included in the test were the samples of one-clause plausible and implausible sentences used in Experiment 1. As would be expected, the percentage number of words correctly reported (79 %) for plausible sentences was considerably higher than for implausible sentences (58x), thus demonstrating that the technique is sensitive to plausibi1ity.l However, for the reversible and nonreversible sentences, there were only very small differences favoring the nonreversible versions : The predictability values for the reversible and nonreversible items used in Experiment 2 were 63% and 65x, and for Experiment 3 the corresponding values were 54% and 56 %. Neither of these differences was significant. The design of the experiments followed the design of Slobin (1966), and each consisted of a 2 x 2 factorial, the factors being syntactic type (actives vs. passives) and reversibility (reversible vs. nonreversible). If the reversibility effect is genuine, then the processing times for reversible sentences should be longer than for nonreversible sentences, and passives should require longer times than actives only for the reversible case. The same procedure was followed in both experiments, the only difference between the two experiments being the actual items used.

1. The correlation between plausibility and predictability can be estimated more precisely using the judgments of plausibility obtained for these sentences in the original study (Forster and Ryder, 1971, p. 292). The ob-

tained product-moment correlation between the plausibility judgments and the mean percentage number of words reported for each sentence was .55, p < .02.

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Method The first step involved constructing a basic set of sentences, half actives and half passives. Each of these sentences was reversible. The active sentences contained five words and the passives contained seven words. Each of these sentences was then converted into a logically nonreversible sentence by changing either the first or the second nominal, ensuring that the nonreversible and reversible versions were, on the average, equally plausible. The average word length was also equated. Examples of the items are as follows: Reversible : Nonreversible Reversible : Nonreversible:

Four : Four Some Some

women touched the girl. women touched the skirt. teachers were dismayed by the parents. teachers were dismayed by the essays.

The sentences are listed in the Appendix. It will be observed that the constraints imposed by the design make many of the sentences relatively unnatural, but it was intended that this would have occurred equally often for reversible and nonreversible sentences. All the active sentences were of the general form NP, . . V . . . NP, and all passive sentences were of the form NP, . . . be . . . V . . . by NP,. Thus the passives are always two words longer than the actives. This means that any difference in the processing time required for actives and passives will be partly due to structural differences and partly due to differences in number of words. The procedure for measuring processing times was the same as in the preceding experiment. The sentences were presented in a random sequence by means of a slide projector, and subjects pressed a key if the sequence of words formed a meaningful sentence; otherwise no response was made. Two sets of materials were used in each experiment (set A and set B). Each set contained actives and passives, half of each sentence type being logically nonreversible, half being reversible.2 If the reversible version of a given sentence were used in set A, then set B contained the nonreversible version, and vice versa. Thus, no single S received both the reversible and nonreversible versions of a given item. In Experiment 2, each set contained 32 sentences, and in Experiment 3, each set contained 24 sentences. None of the sentences used in Experiment 2 was used in Experiment 3. The number of distracters in each experiment equalled the number of test items. Basically, these distracters were designed to superficially resemble the test items. Typical examples are as follows : 2. Three of the nonreversible sentences used in Experiment 3 are actually only pragmatic-

ally nonreversible.

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That thought the woman was by person. A poor substitute the amused. The woman was only eaten the uncle. The number light under side. He was in also more. The full measure was filled by empty. In each experiment,

20 undergraduate

volunteers

served as subjects.

Results The decision mean latencies Table 2. The way factorial (active-passive)

latencies were analyzed in the same way as in Experiment 1, and the over subjects in each condition for the two sets of items are reported in results for Experiments 2 and 3 were analyzed separately in a threedesign, the factors being materials (Set A or Set B), sentence type and reversibility, with repeated measures on the last two factors.

Table 2. Mearz adjusted latencies (in msec) as a funtion qfsentence type in Experiments 2 and 3

Active Passive Difference

Experiment 2 Reversible Nonreversible

Experiment 3 Reversible Nonreversible

1023 1201

1058 1213

1037 1191

1072 1246

178

155

154

174

In order for the reversibility argument to be sustained, there are two essential requirements. First, reversible sentences must be more difficult to process than nonreversible sentences, and second, the difference between actives and passives must be substantially reduced fc.r nonreversibles compared with revel sibles. Neither requirement was satisfied in either experiment. First, in both cases, reversibles were slightly easier to process than nonreversibles, but this effect was significant only in Experiment 3, F(1,18) = 9.16, p < .Ol. Second the interaction of sentence type and reversibility was not significant (F< 1) in either experiment, and in the case of Experiment 3, the difference between actives and passives was actually greater in the nonreversibie condition. The only evidence of an interaction effect came from the subsidiary analysis of the reciprocals in Experiment 3, F(1,18)=4.93, p < .05, but this makes little sense, since it implies t!lat nonreversibility interferes with the processing of passives to a greater degree than for actives. Neither this effect, nor the significant reverse effect of reversibility in Experiment 3, was significant in the item analyses.

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The only effect reaching significance in all analyses (including the item analyses) was the difference between actives and passives. This was significant at the 1% level in each case, with the E: values ranging from 14.10 to 76.61.

Discussion

Taken together, Experiments 2 and 3 provide a surprising disconfirmation of an almost universally accepted empirical fact. There can be no doubt that under the conditions of these experiments the reversibility of the NPs has little relevance for sentence processing. The implication of this result is either that the previously reported reversibility effects were in some way artifactual, or that the decision latency task does not adequately reflect total sentence processing time. We shall return to the first alternative later and for the present concentrate on the possibility of inadequacies in the experiments reported here. The most obvious possibility is that the subjects of the experiment were able to develop special strategies so that the decision latencies did not accurately index sentence processing time. For example, subjects may have been able to correctly classify sentences without completely processing the syntax or meaning of the sentence. In the case of a reversible sentence, for instance, there is no need to determine which NP is the logical subject and which is the logical object, since both versions would be well-formed. On the other hand, nonreversible sentences might require more detailed syntactic processing, since one of the possible arrangements of NPs would be anomalous. This might explain why reversibles were no more difficult to classify than nonreversibles, but would not explain why a large active-passive difference was found for both types of items. Another possibility is that little attention was paid to the meaning of the sentence, since the distracters were all ungrammatical, and hence there was no need to consider the meaning to arrive at a correct decision. The only way to ensure that both syntax and meaning are accurately analyzed is to manipulate the properties of the distracters so that errors will be made whenever an item is not fully processed. Thus, if some of the distracters are grammatical actives or passives, but are semantically anomalous, we can determine how much attention is paid to meaning by examining the error rates on these items. If meaning is routinely ignored, then the error rate should be close to 100%. Similarly, if some of the distrac:ors are meaningful actives or passives, but contain minor syntactic errors, then we can determine how accurately the syntax is being processed by examining the error rates on these items. The next experiment examines the effects of including distracters of the above types.

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Experiment 4 In this experiment, the test items were the sentences used in Experiment 3. However, instead of constructing a set of distracters that were merely superficially similar to sentences, the distracters were carefully designed so that in all respects, except that of being well-formed, they matched the properties of the test items. The two major classes of distracters used were as follows: 1. Anomalous items. In order to check that the subjects were determining the meaning of the sentences, eight semantically anomalous items were included, half active and half passive. These items were : The man built the cat; The idea o&fled the artist; The reporters printed the senator; The book wrote the author; The artist was painted by the picture; The boy was inserted by the mother; The workers were repaired by the priest; The feet were mentioned by the name. If the subjects were totally ignoring the meaning of the sentence, then it would be expected that a high percentage of errors would be made on these items. Of course, it should be noted that accurate classification of these items as malformed requires accurate processing of syntax as well. 2. Ungrammatical items. These consisted of 24 items, half active and half passive, which contained relatively minor grammatical errors. Within each sentence type, half would have been reversible sentences without the ungrammatical feature, and half would have been nonreversible. These items were based on the sentences used in Experiment 2. The errors consisted principally of changes in the correct word-order, lack of agreement and omission of articles. Typical examples are as follows: Active reversible : Four women the touched girl; The boys seem liked girls; The teacfler saved sorry boy. Active nonreversible: The butcher recognized three hat; The girl the kissedphoto; The plague tflree killed men. Passive reversible: The student were annoyed by the woman; Some were teacfzers dismayed the by parents; Each child were identified by gentleman clever. Passive nonreversible: The doctors was guided by her instinct; The stranger was overcome by now smoke; The statue was rescued quickly by artist. In order to balance the number of sentences and distracters, an extra eight filler sentences were included. The experimental procedure was exactly the same as in the previous experiment, except in the following respects: (i) The subjects were provided with two response buttons, one for a ‘Yes’ response, one for a ‘No’ response (in the previous experiments, the subjects only responded to well-formed sentences). This procedure forces the subject to commit himself as rapidly as possible and produces higher error rates than the alternative procedure used earlier; (ii) the instructions

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stressed the need for careful analysis of the items, with special attention being given to anomalous items. It was stressed that only fully meaningful and grammatical sentences should be responded to with a ‘Yes’ response. The subjects were asked to respond as quickly as possible, without making a large number of errors. A total of 20 undergraduate volunteers served as subjects, and they were paid for their participation in the experiment, Table 3 shows the mean latency obtained in each condition, the method of analyzing the results being the same as in the previous two experiments. The first point to note is that the overall latency has increased markedly in comparison to Experiment 3 (see Table 2), even though the test items are exactly the same. This indicates that the manipulation of the distracters had the desired effect of forcing the subjects to analyze the test items in greater detail. Table 3. Mean adjusted latencies Experiment 4

Active Passive Difference

(in msec) as a function

of sentertce type in

Reversible

Nonreversible

1436 1709

1361 1668

273

307

As in previous experiments, there is a large and significant difference between actives and passives, F(1,18) = 41.64, p < .Ol, with a rather larger effect being obtained in the present experiment. This effect was highly significant in all analyses. However, in contrast to the earlier experiments, reversibles tended to produce longer latencies than nonreversibles, although this effect is marginal. In the analysis of the mean latencies for subjects, the effect of reversibility just failed to reach significance, F(1,18) = 4.39, p > .05, but in the analysis of reciprocals, it reached significance, F(1,18) = 4.79, p < .05. However, in both item analyses, the effect was nonsignificant (F< 1). Whatever the status of this effect, it is not particularly strong and cannot be generalized over items. However, the central point to notice is that the classic reversibility effect is not obtained in that there is a substantial active-passive difference for both reversible and nonreversible items. Whatever interaction between sentence type and reversibility exists, it tends to go in the opposite direction to the predicted effect, with nonreversibles producing a larger difference than reversibles, although this interaction falls well short of significance in the analysis of the subject means, F(1,18) = 0.38, p > .05, with similar results in the other analyses.

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Thus, on the basis of these results, there is no reason to reject the constancy hypothesis, since the slight effects of reversibility are equal for both sentence types. The most reasonable interpretation of the reversibility differences, if they are reliable, is that reversibility has affected either semantic or lexical processing. Furthermore, there can be no argument in this experiment about whether the subjects were in fact processing the sentences accurately. For six of the eight anomalous distracters, all twenty subjects responded correctly by rejecting the item as a meaningful sentence. Of the seven errors that occurred (equivalent to an error probability of .04), five were on the item The man built the cat, where there is some justification for arguing that the item was, in fact, perfectly well-formed. Thus performance on the anomalous distracters was virtually perfect, and there is no way in which this could be achieved without determining the meaning of every item in the experiment. This assumes, of course, that the error rate for the test items was also low, which was in fact the case: Over all items, the error probability was only .05. A similar conclusion applies to the processing of the ungrammatical distracters, although the error rates tended to be a little higher. For distracters based on active sentences, the error probability was .07, and for passives the value was .18. For 16 of the 24 ungrammatical distracters, at least 90% of the subjects correctly rejected the item, and the majority of errors were on items where errors of number were involved (e.g., The statue was rescued quickly by artist; The doctors was guided by her instinct).

Experiment 5 The final experiment again examines the reversibility issue, this time using a quite different experimental task. It might be argued that the decision latency technique represents an unnatural situation, somewhat analogous to proof-reading, in which the subject is asked to attend to relatively minor technical details of syntax, rather than attempting to interpret the input in a meaningful way. Accordingly, it was decided to use a different task, which places considerable emphasis on the subject’s ability to rapidly organize the input in meaningful terms. The task chosen was the rapid serial visual presentation (RSVP) technique, which had also been used in the original experiment of Forster and Ryder (1971). Briefly, this technique involves presenting each word of the sentence successively at an extremely rapid rate (16 words/set) with the subject merely being required to report as many words as possible. Each word is visually superimposed on the preceding word, which prevents the formation of a cumulative sensory trace of the entire sentence and forces the subject to process the input at the same rate as it is presented. The assumption underlying the procedure is that the presentation rate is slow enough to permit

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each word to be identified but too fast to allow each word to be separately encoded into memory. However, if the subject is able to organize the input meaningfully, then the encoding operation is assumed to be far more rapid. That is, the rapid presentation rate essentially causes the subject to forget much of what he has seen, unless he can impose a meaningful organization on the sequence. Although there is obviously some doubt as to whether the subjects can always identify every word, this is not an important issue in the present context, since there is no reason to expect purely visual factors such as forward or backward masking effects to differ systematically as a function of syntactic or semantic variables. The precise details of the procedure and evidence indicating the suitability of the technique are available elsewhere and will not be repeated here (Forster, 1970; Forster and Ryder, 1971; Holmes and Forster, 1972; Holmes, 1973). The items used in this experiment were very similar to the test items used in the preceding experiments and consisted of 24 sentence-pairs, with one member of each pair being logically reversible, the other logically nonreversible. As in the earlier experiments, half the items were actives and half were passives, with the reversible and nonreversible versions being identical except for one of the NPs. The actives were all seven words in length, and the passives were all nine words in length. The procedure for checking the predictability of the sentences was also the same as in the earlier experiments. The results of this analysis showed no significant differences in predictability as a function of reversibility. As in previous experiments, two sets of materials were prepared. The sentences were filmed so that each word occupied a single frame of a 16 mm movie film, with a ready signal preceding the sentence. The sentences were presented by means of a variable speed motion analyzer projector at a speed of 16 frames/set. After each sentence had been presented, the subject was asked to write down as much as possible, with no constraints being placed on guessing. Two films were prepared so that if the reversible member of a sentence-pair was included in the first film, the nonreversible member was included in the second. A total of 20 subjects were used, half being assigned to each film. In scoring the responses, it was necessary to select a procedure which allowed comparisons between actives and passives. The normal measure, number of words correct, is inappropriate since the passives were longer than the actives. The simplest method (to be referred to as method L) is to score the number of key lexical items reported, these items being the two NPs and the verb. This has the virtue of being relatively objective and allows a direct comparison of actives and passives. However, it ignores the question of whether the subject understands the grammatical and semantic relations between these items. This problem can be overcome by scoring extra points for reporting the grammatical relations correctly. That is, not only would the

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subject receive one point for reporting the logical subject of the sentence, he would get an extra point if it were also clearly the logical subject of his reported version, similarly for the logical object, and the voice of the verb. Thus the maximum score for a sentence would be 6, and this would indicate that the essential features of the meaning of the sentence had been correctly reported. However, this technique (referred to as method S) also involves an element of subjectivity in the scorer, and it is for this reason that both sets of results are reported. Table 4 shows the mean scores in each condition under both scoring systems. For scoring system L, the maximum possible score is three, and this is obtained if all three key lexical items are reported (inflections and order ignored). For scoring system S, the maximum possible score is six, and this is obtained if all three key lexical items are assigned the correct underlying grammatical function. Fortunately, the overall pattern of the results is identical for the two scoring systems. In both cases, there is a highly significant difference between actives and passives, F(1,18) = 25.64, p < .Ol for scoring system L, and F(1,18) = 23.92, p < .Ol for system S. However, for both analyses, neither the main effect of reversibility, nor the interaction of reversibility with sentence type was significant, F < 1. Table 4. Mean number of key lexical items (L) and mean semantic score (S) per sentence in Experiment 5

L

Reversible S

Nonreversible L S

Active Passive

2.18 1.84

4.21 3.24

2.13 1.83

4.13 3.26

Difference

0.34

0.97

0.30

0.87

Thus, once again there is no reason to reject the constancy hypothesis, since reversibility fails to influence the difference in performance on actives and passives.

General discussion The general conclusion to be drawn from the last four experiments seems inescapable: Under the conditions of these experiments, reversibility has very little impact on sentence processing. Why, then, was the effect of reversibility so pronounced in the experiments of Slobin (1966) and Herriot (1969)? The answer may lie in the nature of the items used. In the present experiment,

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every effort was made to ensure that the reversible and nonreversible items were equivalent in all respects except reversibility; they differed only in one NP and were also matched for associative predictability. On the other hand, it is possible that in the earlier experiments, the nonreversible items tended to be more predictable, but it should be noted that this confounding would produce an equal facilitation for both actives and passives. Thus, an overall effect of reversibility could be explained in this way, but not an interaction between sentence type and reversibility. It is of interest to note a further property of the items used in this paper: The verbs necessarily had to be capable of appearing in both reversible and nonreversible sentences (since the verb was held constant). However, this was not necessarily true in the earlier studies. For example, it is difficult to construct a reversible counterpart for the nonreversible item The girl is watering the flowers merely by changing an NP. That is, the verb water appears more naturally in nonreversible environments.3 The tasks used by Slobin and Herriot also differ in important ways from the tasks we have used. The technique used by Slobin (1966) was the verification task, in which the subject must decide whether the sentence is a true description of a subsequently presented picture. There are several reasons for doubting results obtained with this procedure. First, as Gough (1966) has shown, there is some doubt that the verification task measures sentence processing time at all, but measures instead the time taken to compare sentence meanings with interpretations of pictures. Second, there is no guarantee that the various pictures are all equally easy to interpret. For example, if we take a nonreversible sentence, The girl kissed the photo, the appropriate picture may be quite easily interpreted. All that needs to be established is whether the picture contains a girl and a photo, and whether the action depicted is kissing. But in the reversible sentence The girl kissed the nurse, there may be some doubt as to who is doing the kissing. In fact the very nature of reversibility suggests that this may be a regular feature of the reversible picture. Third, it appears that the range of possible pictures which can follow reversible and nonreversible sentences must differ. For example, the reversible sentence The dog is chasing the cat can be followed by a picture of a dog chasing a cat, a cat chasing a dog, or something else altogether. However, the 3. This suggests a classification of verbs as reversible or nonreversible. Verbs such as defuse or repair would almost always occur in nonreversible sentences, whereas verbs such as promise or resemble would almost always occur in reversible sentences. A further suggestion is that the property of reversibility resides in the verb rather than in the sentence, which would explain the lack of reversibility effects observed here, since, on this classification, all the verbs would have been neutral,

i.e., occurring with equal probability in either kind of sentence. However, in several subsidiary experiments, using both the decision latency and the RSVP technique, no evidence has been found to support this notion. These experiments used sentence pairs such as The lecturer knew/taught the student: The soldier was recognized/dismissed by the general. In

all cases, the usual activepassive effect was obtained, but there was a total absence of any effect of reversibility.

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nonreversible sentence The girl is watering theflowers can be followed by a picture of a girl watering flowers or something else altogether, but not by a picture of flowers watering a girl, unless anomalous pictures are used. This suggests that the verification of a nonreversible sentence can be carried out at an earlier stage of processing than for a reversible sentence, and in some accounts of this experiment (e.g., Morton, 1966) it is explicitly assumed that syntactic processing is quite unnecessary for the nonreversible sentence to be verified. This is not a weakness of the experiment by any means, but if this account is correct, it means that the experiment tells us nothing about whether reversibility facilitates syntactic processing. These problems were avoided by Herriot (1969), who measured the time taken to give the logical subject and object of the sentence, in that order. While this task cannot be dismissed entirely, it is open to obvious strategy effects, and it is an open question whether the task reliably measures sentence processing time. The principal difficulty is that it is probably far easier to give the logical subject and object when the order in which they must be reported is the same as the order in which they occur in the sentence. The decision latency technique used in Experiments 1-4 does not appear to suffer from the same weaknesses. There is no simple strategy that can be adopted, provided that the distracters are suitably designed. In Experiment 4, where the distracters were made as similar as possible to the test items, any attempt to base a decision on an incomplete analysis of the syntax of the sentence would produce a high error rate. Similarly, any attempt to ignore the meaning of the sentence would have produced high error rates on the semantically anomalous distracters. Even in the experiments where the distracters only superficially resembled the test items, it seems likely that both syntax and meaning were processed, since in all experiments, the active-passive difference was substantial, and in Experiment 1, there was a large effect due to both number of clauses and plausibility. However, it must be conceded that the decision latency task might introduce a certain artificiality, in that the precision of processing required is probably higher than in normal sentence processing. That is, the subject must behave more like a proof-reader than is normally the case. But this is not a deficiency in the technique; the goal is to understand how we process the syntax and meaning of sentences under a variety of conditions, not just a particular set of conditions where there is little premium placed on accuracy. By manipulating the properties of the distracters, we can potentially select any degree of precision we wish. It is interesting to note, incidentally, that it was only in Experiment 4, where the requirements were the most stringent, that any sign of an effect of reversibility was apparent. In this case, however, the effect (weak as it was) was equal for both actives and passives, thus supporting the constancy hypothesis.

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The RSVP technique used in Experiment 5 potentially allows for quite different processing. The main weakness of the technique is that the subject must report the original sentence, which means that the report can be contaminated by the effects of guessing. This presents no special problems in the current situation, since the sentences were equated for predictability. However, the RSVP task differs from the decision latency task in that there is no reason why the subject must process the syntax at all. In the decision latency task, even if the meaning of the sentence had been correctly guessed on the basis of lexical information, the input string still had to be checked for grammaticality. But in the RSVP task, it is generally assumed that the critical factor governing performance is how rapidly the meaning of the sentence can be determined. Hence, if the meaning had been processed through channel B, then this would facilitate the subject’s report. If, as was suggested earlier, the meaning of nonreversibles can be determined without having to rely on syntactic analysis, then we should have observed a large effect of reversibility in Experiment 5. The fact that no effect occurred implies either that B-type processing did not occur at all or that it was too slow to be of any assistance. Further, the fact that a strong active-passive difference was found for both reversible and nonreversible items implies that syntactic processing was, in fact, attempted. In conclusion, we believe that the evidence presented here is sufficient to call into question the generality of the reversibility phenomenon. If this is accepted, then it appears that the case for the interactive hypothesis collapses, leaving the constancy hypothesis as the only viable alternative. It should be noted that the constancy principle does not require that syntactic analysis always precede semantic analysis, nor does it imply that there are no circumstances in which the meaning of a sentence could be obtained without syntactic analysis. The correct inference is that when syntactic analysis is required by the task conditions, it is executed without regard for the meaning of the sentence. This conclusion tends to suggest that there must be a psychologically real level of description which is purely syntactic, and quite independent of the semamic representation. Thus, we conclude that there is no evidence to indicate that the number of possible syntactic analyses of the sentence is reduced by the operation of semantic heuristics that apply prior to or during syntactic analysis. If such heuristics exist, then their operation must be so limited that they operate in exactly the same way, regardless of whether there is or is not a plausible semantic organization of the sentence (and, according to Forster and Ryder, 197 1, even if the sentence is semantically anomalous), and regardless of whether the sentence is reversible or nonreversible. Nevertheless, it is quite clear that semantic heuristics play an important role in sentence processing, as shown by the very strong effects of plausibility in Experiment 1. We are now in a position to argue that the locus of this plausibility effect is more likely

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to be in the semantic processing stage than in the syntactic stage. Evidently, semantic processing is organized in such a way that plausible meanings can be assigned more rapidly than implausible meanings. At the moment, we are unable to specify more precisely what is involved in plausibility. It may simply reflect variations in the associative connections between lexical items (e.g., Rosenberg and Jarvella, 1970; Collins and Quillian, 1972) or it may reflect something more abstract, such as the difficulty of constructing a reasonable context for the sentence. Whatever the nature of these effects, it seems likely that semantic interpretation must involve a heuristic stage of processing, in which hypotheses about the probable meaning of the sentence are formulated and tested, along the lines of analysis-by-synthesis routines.

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Appendix Sentences used in Experiment 1 Sentences are grouped by syntactic structure. and the second is the implausible version.

The first sentence is the plausible

version

The aborigines were shown a rusty The officials were given a warm reception. invention. Five girls waded into the large pool. Three bugs jumped over the mouldy meat. The wealthy child attended a private school. One gentle ghost haunted a scared parson. Some events greatly troubled the serious students. Their noise slowly deafened the pretty minister. The hungry boy found same dry bread. The clever fly made some tiny drugs. Several children raced to the burning building. Several lawyers rushed to the falling passage. The foreign film was an acclaimed success. The hideous plot was a continued failure. Nobody laughed at the boy’s silly mistake. Nobody climbed to the god’s frozen shrine. The queen danced at the ambassador’s ball. The author stared at his neighbour’s elbow. John smoked cigars throughout the dreary play. Mary chewed spears throughout the corrupt talk. The solicitor she wants is busy elsewhere. The daughter she hates is angry somewhere. The dress that Pam wore looked ugly. The aunt that Jim ate tasted foul. They expected their soldiers to approach quietly. They imagined their audience to applaud lightly. Your singing loudly disturbed the entire assembly. Her dying suddenly disrupted the amazing banquet. The choir sang hymns while we prayed. The babies rang bells while he fired. Having animals near us is terribly upsetting. Seeing libraries near us is slightly inviting. His father knew that he disliked marriage. His infant said that he inspected letters. Having aroused him she then left quickly. Having arranged him she then read bravely. The police accused us of trespassing again. The judge charged us with undressing often. Sue hoped nobody remembered the awful scene. Joan guessed nobody recognized the living form. Sentences used in Experiment 2 Reversible versions take the second.

take the first nominal

in parentheses,

and nonreversible

versions

Four women touched the (girl, skirt). The butcher recognized the (man, hat). The boys liked the (girls, books). Poor John needed (his companions, some attention). A man treated the (farmer, disease). The girl kissed the (nurse, photo). The teacher saved the (boy, box). A cleaner discovered the (watchman, suitcase). The (girl, smell) disturbed the woman. The (guest, game) entertained the boys. The (doctor, plague) killed three men. The (agent, idea) surprised the model. The (youth, game) tired the

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minister. That (woman, sheet) covered the girl. Six (women, banners) welcomed the crowd. The (horse, mask) frightened the thief. Many students were aided by the (woman, rules). The doctor was guided by his (servant, instinct). Some teachers were dismayed by the (parents, essays). The stranger was overcome by the (sailor, smoke). The student was annoyed by the (woman, noise). A woman was upset by the (crowd, photo). Most children were pleased by the (performers, performance). Stupid John was misled by the (traveller, signpost). (Uncle Bill, Bill’s face) was shaved by uncle Alan. A (tiger, deer) was attacked by a panther. The (general, proposal) was praised by the committee. The (woman, shirt) was washed by the girl. Each (child, vase) was identified by the gentleman. The (man, ban) was lifted by the king. The (student, statue) was rescued by the artist. The (builder, machine) was employed by the electrician. Sentences

used in Experiment

3

Five boys guarded the (man, cave). The boy saw six (officers, flowers). Uncle Jim forgot the (boy, box). The man seized the (robber, vessel). This person knew the (man, game). The boy kicked the (stranger, football). Many (warriors, buildings) shielded the army. The (girl, play) offended the workmen. A (worker, noise) interrupted the program. This (man, book) confused the teacher. The (patient, picture) shocked the doctor. The (visitor, program) amused the child. The (dog, moth) was chased by the man. The (parson, parcel) was received by the soldier. The (author, train) was met by the painter. The (woman, animal) was mistreated by the man. The (boy, body) was examined by uncle Charles. The (thief, drum) was beaten by the youth. Big Joan was assisted by the (man, book). Old Bob was saved by (the youth, good luck). The teacher was enlightened by the (speaker, article). Many students were impressed by the (visitors, displays). The warrior was injured by the (rebel, sword). The stranger was hidden by the (negro, grass). REFERENCES Bever, T. G (1970) The cognitive basis for linguistic structures. In J. R. Hayes (Ed.), Cognition and the development of language. New York, Wiley. Collins, A. M., and Quillian, M. R. (1972) How to make a language user. In E. Tulving and W. Donaldson (Eds.), Organization of memory. New York, Academic Press. Dooling, D. J. (1972) Some context elTects in the speeded comprehension of sentences. .I. eXP. Psychol., 93, 56-62.

Fodor, J. A., and Garrett, M. (1967) Some syntactic determinants of sentential complexity. Pert. Psychophy., 2, 289-296. Garrett, M., and Bever, T. G. (1968) Some syntactic determinants of complexity, II: Verb structure. Pcrc. Psychophy., 3, 4.53-461. Forster, K. I. (1970) Visual perception of rapidly presented word sequences of varying complexity. Prrc. Psychophy., 8, 215-221. and Ryder, L.A. (1971) Perceiving the

Semantic

structure

of sentences. J. 10, 285-296. Gough, P. B. (1966) The verification of sentences: The effects of delay of evidence and sentence length. J. verb. Learn. verb. verb.

and meaning

Learn.

verb.

Beh.,

Beh., 5, 492-496. (1972) One second

of reading. In J. F. and I. G. Mattingley (Eds.), Language by ear and by eye. Cambridge, Mass., MIT Press. Herriot, P. (1969) The comprehension of active and passive sentences as a function of pragmatic expectations. J. verb. Learn.

-

Kavanagh

verb. Beh., 8, 166-169.

Holmes, V. M. (1973) Order of main and subordinate clauses in sentence perception. J. verb. Learn. verb. Beh., 12, 285293.

and Forster, K. I. (1972) Perceptual complexity and underlying sentence structure. J. verb. Learn. verb. Beh., 11, 148156. Meyer, D. E., and Schvaneveldt, R. W. (1971) Facilitation in recognizing pairs of words : Evidence of a dependence between retrieval operations. J. exp. Psychol., 90,

-

227-234.

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Morton, J. (1966) Comments on J.P. Thorne’s paper. In J. Lyons and R. J. Wales (Eds.), Psycholinguisticspapers. Edinburgh, Edinburgh University Press. Oldfield, R. C. (1966) Things, words and the brain. Q. J. exp. Psychol., 18, 340-353. Rosenberg, S., and Jarvella, R. J. (1970) Semantic integration as a variable in sentence perception, memory and production. In G. B. Flores d’Arcais and W. J. M. Levelt (Ed%), Advances in psycholinguistics. Amsterdam, North-Holland. Rubenstein, H., Garfield, L., and Millikan, J. A. (1970) Homographic entries in the internal lexicon. J. verb. Learn. verb. Beh., 9, 487-492.

Schank, R. C. (1972) Conceptual dependency: A theory of natural language understanding. Cog. Psychol., 3, 552-631. Schlesinger, I. M. (1968) Sentence structure and the reading process. The Hague, Mouton. Slobin, D. I. (1966) Grammatical transformations and sentence comprehension in childhood and adulthood. J. verb. Learn. verb. Beh.,

5, 219-227.

R&urn&

Dans cette ttude on cherche g verifier si le temps attribuable au calcul syntaxique d’une phrase est fortement influencC par les proprittts semantiques de cette phrase. Une strie d’expkriences oti l’on utilise deux types de proddures, ne permet pas de soutenir cette position. Plus exactement, ces exp&iences montrent que le temps de calcul tend g &tre constant pour des phrases ayant des plausibili-

t& stmantiques vari&es lorsque ces phrases ont une m&me structure syntaxique. Ces exp&iences montrent Cgalement que la reversibilitd n’affecte pas de facon systkmatique le calcul de la phrase. Ces faits sont in&p&t& comme indiquant que la recherche de la structure sous-jacente d’une phrase depend des propri&% syntaxiques de l’input.

Discussions

Is there

Neo-Piagetian any support

training experiments revisited for the cognitive-developmental stage hypothesis? CHARLES

:

J. BRAINERD

University of Alberta

In a recent number of this journal, Strauss (1972) reviewed some of the many experiments designed to induce and/or extinguish concrete-operational reasoning skills which have appeared during the past decade and one-half. In view of the fact that several other reviews of this literature already exist (e.g., Beilin, 1969, 1971b; Brainerd and Allen, 1971a; Hatano, 1971; Hooper et al., 1971; Glaser and Resnick, 1972) it might seem improbable that Strauss’ review would have anything fundamentally new to offer. However, Strauss’ review is quite novel. He examines the relevant literature with an eye toward determining whether or not the weight of the evidence favors Piaget’s hypothesis that mental growth is a stage-like process. The review begins with a synopsis of the ‘organismic stage hypothesis’. The bulk of the paper then consists of an extremely selective three-part review which convinces Strauss that ‘the findings of the studies tended to support most of the hypotheses generated from this approach (p. 329). It must be observed that Strauss’ rather conservative-sounding conclusion would be somewhat momentous if it happened to be true in a nontrivial way. It is the first time in recent memory that anyone has suggested that there is some well-established branch of the developmental literature that provides consistent support for the stage hypothesis. Historically, the assumption that any aspect of behavioral development (personality, perception, cognition, etc.) is stage-!ike has not enjoyed widespread acceptance among developmental psychologists. The lack of popularity of the stage hypothesis is due primarily to the prima facie inconsistency between the notion of a succession of qualitatively distinct behavioral states and the very continuous-looking data base that has accumulated over the years (Kessen, 1962). Also, the stage hypothesis has proved to be conceptually intractable and, as a result, it has acquired a well-deserved reputation for protean meanings (e.g., cf. Flavell, 1971). In fact, a rather substantial majority of developmental psychologists tend to believe that the stage hypothesis is hopelessly philosophical and incapable of direct empirical evaluation (Beilin, 1971a; Brainerd, 1973a). With reference to the Piagetian stage hypothesis, Cognition 2( 3), pp. 349-370

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recent attempts to explicate this particular version of the stage hypothesis (e.g., Beilin, 197la; Dagenais, 1973; Flavell, 1971; Pinard and Laurendeau, 1969) have not produced any definitive conclusions about how it might be confirmed or disconfirmed. These preliminary observations concerning our long-standing doubts about the merits and, indeed, the very meaning of the stage hypothesis suggest that considerable prudence is warranted whenever claims of even meager support for the hypothesis are advanced. Concerning Strauss’ claim about the Piagetian version of the stage hypothesis, we would do well to subject the evidentiary conclusions which led to this claim to rather circumspect analysis. We can ask at least two questions about each of these evidentiary conclusions: (a) Does the literature actually support the conclusion? (b) Regardless of whether or not the literature actually supports a given conclusion, does the conclusion itself provide nontrivial evidence for the Piagetian stage hypothesis? Concerning a, I already have observed that Strauss’s review is quite selective. By my count, roughly half the relevant experiments are cited. Moreover, those experiments which are cited in conjunction with this or that conclusion typically are mentioned only in passing and are not discussed in detail. Therefore, it is possible that a more comprehensive survey of the literature would fail to support some of Strauss’ principal conclusions. Turning to question b, Strauss frames his evidentiary conclusions as predictions from the ‘organismic-developmental stage hypothesis’. That is, they are cast as findings that obviously follow from the familiar stage-related distinctions about cognitive development that Piaget has promulgated over the years. Because these findings may be said to follow from Piaget’s stage hypothesis, Strauss indicates they may properly be regarded as providing support for the hypothesis itself. This line of reasoning begs a very important question. One can adduce two general types of evidence for any scientific hypothesis - trivial and nontrivial. Trivial evidence takes the form of findings (logical or empirical) that are consistent with both the hypothesis of interest and with its chief competitors. Virtually all investigators would accept and/or predict such findings - not merely those who happen to subscribe to the hypothesis in question. Findings of this sort are not very interesting or informative because they are not unique to the hypothesis; we are not any better off with them than without them. Nontrivial evidence, on the other hand, consists of logical or empirical findings which are more or less unique to the hypothesis. Findings of this sort are interesting and informative because they are both consistent with the given hypothesis and inconsistent with other hypotheses. As is also the case for most of Piaget’s writings on the stage hypothesis (e.g., Piaget, 1956, 1960, 1973, Ch. 3), the question of trivial vs. nontrivial evidence is not broached in the synopsis that precedes the main body of Strauss’ review. Hence, it is not clear a priori that any of the training-related predictions contained therein are of the nontrivial variety. In fact, we shall see below

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that some of these predictions (e.g., subjects who already possess a concrete-operational concept in part will perform better on post-training tests than subjects who do not possess it at all) definitely fall in the trivial category. Of the two questions just posed, I shall deal primarily with question a in this paper. [I have dealt with question b elsewhere (Brainerd, 1973a) and it appears that the key nontrivial predictions of the stage hypothesis are essentially typological in nature. That is, the evidence required to confirm the stage hypothesis in conjunction with any domain of behavioral development is roughly the same as the evidence that would be required to verify a type theory for that domain]. I shall consider in turn the major evidentiary conclusions advanced in each of the three sections of Strauss’ review. In each cast, we shall see that the literature provides at least as much disconfirming as confirming evidence. In some cases, we shall see that the available evidence appears to be predominantly negative.

Review of evidentiary conclusions 1.

The triter ion problem

Strauss gives brief consideration to the bothersome criterion problem in neo-Piagetian research before launching the review proper. The criterion problem, which has been discussed by a great many investigators (e.g., Beilin, 1971b; Braine, 1959, 1962, 1964; Brainerd, 1973b, 1973c, in press, a; Brainerd and Allen, 1971a; Gruen, 1966; Inhelder and Sinclair, 1969; Reese and Schack, in press; Smedslund, 1963, 1965, 1969) is concerned with the minimum behavioral evidence which we demand before we are willing to infer that a given subject possesses a given concrete-operational concept. The Genevans, who for reasons unknown to this writer will tolerate large numbers of false negative errors (diagnosing a present concept as absent) for the sake of avoiding even a very small number of false positive errors, employ rather strict criteria. Non-Genevans, who view false negative and false positive errors as equally objectionable, tend to employ less stringent criteria. In the past, reviewers of the neoPiagetian training literature have taken more or less neutral positions on the criterion issue. In contrast, Strauss maintains that one must adopt a definite stance on this issue prior to undertaking a literature survey. Without any further substantive analysis of the criterion problem, Strauss simply proceeds to adopt what he contends is the Genevan criterion : ‘The most stringent criterion has been accepted as the most powerful assessment tool. This criterion has been established by Piaget and his co-workers (c$, Inhelder and Sinclair, 1969). Here S is assessed to be at the concrete-operations

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stage for conservation concepts if he: (1) Makes a correct judgment of equivalence, (2) logically justifies that judgment, (3) successfully resists a verbal countersuggestion, and (4) produces a successful performance on a related behavioral task’ (p. 332). There are several objections which can be lodged against Strauss’ arbitrary advocacy of the preceding criterion as the appropriate prism through which to view the literature. To begin with, three of the four parts of the criterion simply are not points of disagreement between Genevan and non-Genevan researchers. Obviously, both groups invariably employ simple judgment responses (part one) and both groups also routinely test for a given concept in at least two stimulus settings (part four). In neoPiagetian training experiments, part four consist of so-called specific transfer tests (cf., Brainerd and Allen, 1971a; Glaser and Resnick, 1972). Part three also is not a point of contention because the Genevans themselves do not routinely employ counter-suggestion with concrete-operational concepts other than conservation. Hence, as I have observed elsewhere (Brainerd, 1973b), the criterion problem can be reduced to a dispute over whether simple judgment responses or judgments-plus-explanations comprise the minimum necessary basis for inferring the presence of a given concreteoperational concept. This brings us to the second problem. To the extent that Strauss accepts the criterion ‘established by Piaget and his co-workers’, he is opting for judgments-plus-explanations in preference to judgments-only. However, the judgments-plus-explanations criterion does not appear to follow from Piagetian theory. This no doubt seems surprising to most readers. It seems only natural to assume that Piaget’s criterion would square with his theory. It does not, however. I have shown elsewhere (Brainerd, 1973b, in press, a) that a theoretical rationale for judgmentsplus-explanations cannot be constructed and that the methodological rationales for the criterion which have been advanced previously (e.g., Smedslund, 1963, 1969) are non-sequiturs. Third and finally, the criterion problem is something of a straw man from the standpoint of the training literature. The principal findings of this literature are not seriously affected by the choice between judgments-only and judgments-plusexplanations. There is no substantial correlation between criterion and presenceabsence of training effects. Instead, as Allen and I observed in our earlier review, ‘the relation between success in training conservation and stringency of criteria is about zero’ (Brainerd and Allen, 1971a, p. 131). The typical finding has been that a given training effect is observed with both judgments-only and judgments-plusexplanations and that the effect is slightly more pronounced for judgments-only. Thus, I do not believe that it is very important to take a rigid position on the criterion problem prior to reviewing neo-Piagetian training experiments. This is not to say that the choice between judgments-only and judgments-plus-explanations is not important for other segments of the neo-Piagetian literature. In cognitivedevelopmental sequence research, for example, the choice between these two criteria

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apparently exerts a very pronounced effect on the findings (c$, Brainerd, 1973c, in press, a; Brainerd and Brainerd, 1972; Gruen and Vore, 1972). In those cases where a clear criterion choice is important, the available evidence favors judgments-only. 2.

Training experiments

Pursuant to his aim of using training data to make inferences about Piaget’s stage hypothesis, Strauss does not review the literature exhaustively. Instead, he establishes three a priori categories of experimentation which he contends are relevant to the stage view and reviews only studies which may reasonably be interpreted as falling in one or more of these categories: ‘Three classes of training have been investigated experimentally which are either derived directly from or are theoretically consistent with the organismic stage hypothesis of cognitive development. The three kinds of training focus upon (1) disequilibrium, (2) mental operations, and (3) regression’ (p. 332). The implication of this statement is that although the review is not intended to be exhaustive vis-&vis the literature in general, it is intended to be exhaustive vis-ri-vis the three categories. However, it turns out that major lines of experimentation were omitted from each of the three categories. The findings from these other lines of experimentation tend to be inconsistent with Strauss’ evidentiary conclusions. 2.1

Disequilibrium experiments

One of the best-known tenets of the Genevan model is that the cognitive equilibrium (either whole or partial) is a defining attribute of each of the various stages of mental growth while cognitive disequilibrium is a defining attribute of interstage transition. Several years ago, Smedslund (1961a) suggested that this leads one to expect that training methods designed to instill cognitive disequilibrium, which he called ‘cognitive conflict’ treatments, will induce concrete-operational concepts. Smedslund (1961~) subsequently reported a conservation training experiment which seemed to confirm this prediction. Since then, disequilibrium training has been an abiding theme in the literature (~5, Beilin, 1971b; Hatano, 1971). Strauss contends that there are two general types of disequilibrium experiment: (a) Experiments in which disequilibrium is introduced into the cognitive system from the outside (called adaptional disequilibrium) and (b) experiments in which disequilibrium is already present in the cognitive system (called organizational disequilibrium). 2.1 .I Adaptional disequilibrium. Under this subheading, Strauss groups only experiments in which some variant of Smedslund’s original cognitive conflict technique (called ‘prediction-outcome’ conflict) have been employed. As other reviewers (e.g.,

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Beilin, 1971b) also have noted, experiments of this type have not been a very promising line of investigation to date. The early successes of both Smedslund and the Bruner-group (Bruner, 1964; Bruner, et al., 1966) have been offset by a number of failures to replicate under more carefully controlled conditions. It has been suggested elsewhere (Beilin, 1971b) that early studies probably succeeded only to the extent that their subjects already possessed the concept being trained. In the case of the Brunergroup’s studies, the lack of control groups may also have been a contaminant. Confronted with the expectation that manipulations of this sort should produce training effects, on the one hand, and the negative findings in the literature, on the other, Strauss attempts to resolve the apparent conflict by discussing some inherent shortcomings of prediction-outcome conflict. He argues, first, that outcomes do not invariably conflict with predictions in this method and, second, that the subject may distort objectively discrepant information internally. In the end, the reader is left with no clear statement about whether or not concrete-operational concepts can be induced via adaptional disequilibrium treatments. From the fact that only prediction-outcome experiments are reviewed, the reader is led to infer either that the prediction-outcome method is the only adaptional equilibrium manipulation that has been studied or that the prediction-outcome method is the only possible manipulation of this type. Neither inference is correct. There are at least three other categories of training treatments which may be viewed as introducing disequilibrium into the cognitive system from external sources: (a) Verbal feedback that is contingent on simple judgment responses; (b) conformity training; (c) dimensional discrimination training. All three types of treatment have been studied in several experiments. Method a is the simplest and, by all indications, the most powerful of the three. During the training trials, the experimenter (who, of course, is an adult authority figure) says ‘You’re wrong’ following each incorrect judgment and ‘You’re right’ following each correct judgment. To date, method a has been shown to induce temporally durable and conceptually generalizable conservation concepts (e.g., Brainerd, 1972a, 1972b, in press, b; Bucher and Schneider, 1973; Figurelli and Keller, 1972; Overbeck and Schwartz, 1970; Siegler and Liebert, 1972) transitivity concepts (Brainerd, in press, b), and class inclusion concepts (Ahr and Youniss, 1970; Brainerd, in press, b). The Brainerd (in press, b) and Bucher and Schneider (1973) studies provide especially strong evidence because all trained subjects were preschoolers. Method b is inspired by social learning theory (e.g., Bandura, 1969) and has been employed only as a conservation induction treatment to data. Conformity is manipulated in two ways in these experiments. First, nonconservers may be paired with conserving peers during the training trials and each dyad instructed to reach a consensual decision on each judgment (e.g., Cloutier, 1973; Murray, 1972; Silverman and Geiringer, 1973). Second, nonconservers may observe an expert model

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(either live or filmed) during the training trials (e.g., Rosenthal and Zimmerman, 1972; Sullivan, 1967; Waghorn and Sullivan, 1970). Temporally durable and conceptually generalizable conservation concepts have been induced by both types of conformity training. Method c also has been employed only as a conservation induction technique. Of the three methods, c bears the closest primafacie resemblance to the cognitive conflict notion originally outlined by Smedslund. Type c training consists of making the conflict between perceptual cues and quantitative cues apparent to nonconservers. The aim is to shift the child’s attention from incorrect perceptual cues to correct quantitative ones (e.g., Gelman, 1969; Halford, 1970; Trabasso, 1968). As is the case for methods a and b, temporally durable and conceptually generalizable conservation concepts have been induced via method c. 2.1.2 Organizational disequilibrium. Under this subheading, Strauss reviews some (by no means all) of the training experiments whose samples have included so-called ‘transitional’ subjects. In Piagetian theory, a truly transitional subject is defined as possessing both preoperational and concrete-operational thinking structures, a condition which Strauss calls ‘structural mixture’. Subjects in the transitional state presumably should be quite susceptible to training experiences. Therefore, the obvious parametric prediction is that subjects diagnosed as transitional should be easier to train than subjects diagnosed as preoperational. As other reviewers have noted (e.g., Beilin, 1971b; Hooper, et al., 1971), several studies have confirmed this prediction. Strauss believes these studies show that ‘children who displayed structural mixture were more likely than those who displayed no measured structural mixture to progressively transform their cognitive structures’ (p. 338). He further believes ‘One can interpret this to mean that structural mixture may be an inherectly unstable state that is particularly susceptible to change’ (p. 338). Although Strauss confesses that these conclusions are post hoc, I think it is fair to say that they also are rather far-fetched. The basic problem is this: In all of the experiments Strauss cites, independent measures of Piagetian thinking structures were never employed. If we are to conclude anything at all about the effects of ‘structural mixture’ on the training of concrete-operational concepts, then we require the following sort of design at an absolute minimum. First, during the pretest phase, we administer tests of the specific concept we wish to train (say, conservation) and we also administer independent tests of Piaget’s eight groupement structures (e.g., Brainerd, 1972c; Hooper and Klausmeier, 1973; Weinreb and Brainerd, 1973). For the training phase of the experiment, we retain only subjects who showed no evidence of conservation on the pretests. After this group of subjects has been identified, we then use their performances on the groupement pretests to divide them into transitional and preoperational subgroups. Next, we train both subgroups on conservation

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and, finally, we administer conservation posttests. If the state of structural mixture actually facilitates conservation induction, then the transitional subgroup should perform better on the posttests than the preoperational subgroup. The crucial thing for the reader to note about the design just outlined is that the behavioral definitions of ‘transitional’ and ‘preoperational’ are independent of the to-be-trained concept, and, therefore, the definitions are not circular. This design was not employed in the studies Strauss cites. The subjects in these studies were classified as transitional or preoperational solely on the basis of pretest performance on the to-be-trained concept. When conservation is the to-be-trained concept, for example, a preoperational subject is one who shows no evidence of conservation on the pretests and a transitional subject is one who either shows consistent conservation in some physical areas but not others or who shows partial conservation in some given physical area. It is obvious that designs of this sort reveal nothing about the effects of ‘structure’ or ‘structural mixture’ because these notions are defined in a hopelessly circular manner. At most, these designs are capable of establishing the trivial and uninteresting fact that subjects who partially possess a to-be-trained concept tend to derive more benefit from training than subjects who do not possess the concept at all. The preceding criticisms are not aimed at the studies in question so much as they are at Strauss’s interpretation of them. None of these studies was designed to investigate the role of ‘structural mixture’. Instead, most investigators employ the transitional-preoperational classification as a device for assessing the power of individual training treatments. If a treatment induces improvements in transitional subjects but not in preoperational subjects, investigators have tended to conclude that the concept in question was not trained (e.g., Beilin, 1969, 1971 b). The assumption underlying this interpretation is that the concept in question is present-in-competence but not present-in-performance in transitional subjects, whereas it is absent from both competence and performance in preoperational subjects (CL Have11 and Wohl-will, 1969). Thus, only performance is trained with transitional subjects but the concept itself is trained with preoperational subjects. By this line of reasoning, the posttest performance of preoperational subjects is the appropriate index of the induction power of a training treatment. Strauss also mentions a small group of studies which he interprets as seeking to induce structural mixture. Although there are too few of these studies to permit any definitive conclusions at present, Strauss believes that they constitute an important line of future investigation. I disagree. The findings of these studies seem just about as predictable and uninteresting as the finding that transitional subjects are more susceptible to training than preoperational subjects. Because these studies do not yet comprise a substantial literature, I shall not defend this contention by discussing the design of individual studies in detail. I simply shall note some general facts about

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all of them that suggest this conclusion. Suppose we have some well-studied domain of concrete-operational reasoning whose constituents are known to emerge in some fixed sequence in normal subjects. For example, suppose classification is the reasoning skill, and we have the three constituent notions of (5) figural sorting of object arrays, (b) exhaustive sorting of object arrays by intension and (c) class inclusion of object arrays. We know from previous normative research (e.g., Inhelder and Piaget, 1964; Kofsky, 1966) that 5, b and c tend to emerge in a fixed sequence: Preschoolers predominantly sort the elements of object arrays into figural groupings; later, by about age 6 or 7, the elements in such arrays are sorted into exhaustive categories by intension (Kofsky, 1966); still later, by about age 10, the class inclusion principle for such arrays is understood (Brainerd and Kaszor, in press; Kofsky, 1966). Suppose we now conduct two types of experiments. First, we train a group of subjects who are at level a on both b and c behaviors. Second, we attempt to extinguish both b and c behaviors in level c subjects. In both cases, a simple cumulative experience argument (which says nothing about ‘structures’ or ‘structual mixture’) yields obvious predictions. In the first type of experiment, we no doubt will find that exhaustive sorting is more readily trainable than class inclusion: The normative data already show that it is the easier of the two to acquire. In the second type of experiment, we no doubt will find that class inclusion is more susceptible to extinction than exhaustive sorting: The normative data show that most subjects have been in possession of exhaustive sorting for three or four years longer than class inclusion. These two rather uninteresting predictions have been the foci of the studies Strauss cites.l

2.2.

Mental operations experiments

Next, Strauss considers studies whose training treatments involve exposing subjects to external analogies of mental operations which Piaget has claimed are involved in

1. We may add to these remarks a criticism that has been advanced by Flavell (1972; Flavell and Wohlwill, 1969). In many cases, the developmental sequences which Piaget reports are logically guaranteed. That is, the sequence simply cannot turn out any other way. The standard illustration of this point is the relationship between the concept of identity in a given physical area and the concept of conservation in that same physical area. Piaget goes to some lengths to show on theoretical and empirical grounds that identity must precede conservation in children’s thinking (e.g., Piaget, 1965). However, his

arguments are, strictly speaking, superfluous: Behaviorally, Piaget defines conservation in terms of identity - i.e., conservation always turns out to be ‘identity plus some other things’ (~5, Brainerd and Hooper, 1974; Elkind, 1967). The identity-conservation sequence therefore is logically guaranteed, and we require no data to confirm it. More important from the perspective of Strauss’s review, no amount of training data could possibly disconflrm such a sequence. Readers who are familiar with Piaget’s research will no doubt be aware of other salient examples of such logically guaranteed sequences in his work.

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the natural ontogeny of the to-be-trained concept. Strauss reviews only experiments in which conservation was the to-be-trained concept. These experiments are grouped into two subcategories: (a) Experiments in which the training manipulation focuses narrowly on one particular operation and (b) experiments in which the training manipulation focuses on two or more operations. For somewhat arbitrary reasons (~5, remarks below), type b treatments are called ‘operational coordination’ training. Strauss concludes that ‘the results indicated that the former strategy [training individual operations] was quite unsuccessful while the latter [training multiple operations] was markedly successful . . .’ (p. 345). However, several experiments are omitted whose findings are inconsistent with the first conclusion. Also, reversibility is confounded with multiple operations in the designs of the studies cited in conjunction with the second conclusion. 2.2.1 Training individual operations. Strauss restricts this subcategory to experiments designed to induce conservation via either addition-subtraction training or inversion reversibility training. Concerning the former, Strauss concludes that ‘the effect of AS training upon conceptual progress to concrete conception [i.e., conservation acquisition] appears to be partial or negligible’ (p. 341). Concerning the latter, Strauss concludes that ‘research related to this mental operation has not been productive in inducing progressive structural reorganization [i.e., conservation acquisition]’ (p. 343). These two conclusions subsequently lead to the observation about the overall ineffectiveness of training individual operations quoted above. Strauss’ conclusion about addition-subtraction is based on Smedslund’s original studies plus the replications of Feigenbaum and Sulkin (1964), Gruen (1965), Smith (1968), Wallach and Sprott (1964), Wallach et al. (1967), and Wohlwill and Lowe (1962). As a group, it is true that these studies do not indicate that addition-subtraction training is a very powerful means of inducing conservation. However, they are not the only available studies on the subject. There is a substantial body of supportive addition-subtraction experiments that has been coming out of Japan since the late 1960s (e.g., Hatano and Ito, 1966; Hatano and Suga, 1969; Inagaki, 1970; Inagaki and Hatano, 1968, 1972). Unlike the experiments Strauss cites, these investigators do not employ exactly the same addition-subtraction procedure as Smedslund. In both the experimental papers themselves and in related literature reviews (Hatano, 1971; Suga, 1966), Smedslund’s original procedure is subjected to methodological criticism. It is argued that, among other things, there is insufficient provision for feedback in the procedure and that if this defect (and certain others) are remedied, additionsubtraction training probably will be more effective. Consistent with this argument, conservation concepts have been induced via the revised procedure. These findings suggest that earlier failures may simply be procedural artifacts. In any case, there are

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insufficient grounds at this time for the conclusion that addition-subtraction training effects are ‘partial or negligible’. Turning to the second conclusion, the statement that reversibility training has ‘not been productive’ runs contrary to statements appearing in other reviews of this literature. Other reviewers have concluded that the available evidence provides substantial support for the effects of reversibility training (cx, Beilin, 1971b; Brainerd and Allen, 1971a; Glaser and Resnick, 1972). The training manipulations of the great majority of successful conservation training experiments cited in these papers either were explicitly designed to provide experience with inversion reversibility or may be interpreted as doing so. Because Strauss does not dispute this fact, we must ask how he fails to reach what others regard as a reasonably safe conclusion. There appear to be three reasons. First, Strauss invokes a variation on the necessary-but-notsufficient objection that Bruner (1964) originally introduced as proof of the ‘irrelevance’ of reversibility to conservation and which Murray and Johnson (1969) subsequently echoed. I have shown elsewhere that this objection is logically flawed in that it contains a converse conditional fallacy: ‘Piagetian theory postulates that both forms of reversibility are necessary preconditions for conservation. Logically, this amounts to a conditional assertion of the form “If conservation, then reversibility”. However, the data which both Bruner and Murray and Johnson believe disproves Piaget’s thesis (the well known fact that some nonconservers possess reversibility) actually disproves the converse of Piaget’s conditional thesis (i.e., “If reversibility, then conservation”) . . . Since the converse of any conditional is invariably fallacious to begin with (c$, Wason, 1966), it is hardly surprising that the data cited by Bruner and Murray and Johnson are inconsistent with it’ (Brainerd, 1972a, p. 116). Strauss’ variation on Bruner’s theme is that reversibility ‘is necessary but not sufficient for concrete operational reasoning. Therefore, one should not expect R training to induce either learning or development’ (p. 342). The latter inference is just as untenable as Bruner’s contention that necessity without sufficiency somehow entails ‘irrelevance’. In view of the close conceptual link between reversibility and conservation, the most reasonable prediction is that reversibility training should prove to be an effective method for inducing conservation. The second apparent reason for the negative conclusion about reversibility training is that most of the successful reversibility experiments cited by previous reviewers are not cited by Strauss. Strauss cites only three successful experiments in his survey of reversibility training (Goldschmid, 1968; Wallach and Sprott, 1964; Wallach et al., 1967). He challenges the latter two experiments on methodological grounds, and he notes that he is insufficiently familiar with the details of Goldschmid’s research to say with certainty that the findings cannot also be dismissed on methodological grounds. (I am familiar with Goldschmid’s research and, insofar as I can determine, it is not sub-

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ject to the possible objections Strauss suggests.) Six other experiments (Bearison, 1969; Beilin, 1965; Gruen, 1965; Rothenberg and Orost, 1969; Smith, 1968; Winer, 1968) whose training treatments previously have been interpreted as focusing on reversibility (c$, Brainerd and Allen, 1971a; Glaser and Resnick, 1972) are postponed until the subsection on ‘operational coordination’. The only rationale for not considering these studies as reversibility training experiments is that their treatments focus on at least one other operation and, therefore, their findings do not establish anything about reversibility training per se. Third and finally, several successful reversibility experiments which are not subject to any obvious methodological challenges are not cited. These studies include Brison (1966), Hamel and Riksen (1973), Schnall et al. (1972), and Roll (1970). The training manipulations of these studies focus narrowly on inversion reversibility, and, therefore, they cannot reasonably be dismissed as multiple operations training studies. Taken together, they provide substantial evidence of the effectiveness of reversibility training. In two of the studies (Hamel and Riksen, 1973; Schnall et al., 1972), for example, transfer of training to untrained concept areas was observed. This sort of ‘far transfer’ has been infrequently observed in other successful conservation training experiments (cJ, Brainerd and Allen, 1971a; Glaser and Resnick, 1972) and has been regarded by previous reviewers as providing perhaps the strongest possible evidence that a training method is effective. We may add Goldschmid’s (1968, 1971) investigations to these studies. Goldschmid’s subjects were given inversion reversibility training in the quantity concept area. The result was temporally durable, generalizable conservation in the quantity area plus considerable far transfer to other concept areas. Within Strauss’s individual operations training subcategory, we may also include a series of investigations on the role of identity in conservation acquisition that Hamel has been reporting (e.g., Hamel, 1971; Hamel and Riksen, 1973; Hamel et al., 1972). Hamel’s findings indicate that training experiences which focus narrowly on identity, produce durable and generalizable conservation in previously nonconserving subjects. In his most recent experiment (Hamel and Riksen, 1973), for example, 20 nonconservers were trained on identity in the concept areas of continuous and discontinuous quantity. Substantial improvements in both quantity conservation judgments and quantity conservation explanations were observed. These improvements continued to be evident one week after training. Moreover, the trained subjects evidenced far transfer to space conservation, number conservation, substance conservation and weight conservation. Thus, a more complete review of the available findings does not seem consistent with Strauss’ apprehensions about addition-subtraction and reversibility training. In both cases, there are considerable amounts of supportive data that are not cited in Strauss’ review. In the explicit case of inversion reversibility training, there appears

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to be strong support for the effectiveness of treatments which focus narrowly on this operation. There also is evidence that the training of at least one other individual operation (identity) induces conservation. 2.2.2 Training multiple operations. Experiments designed to induce conservation by training two or more presumably relevant operations are reviewed in this subsection. Before considering the actual experiments, an argument is advanced to the effect that multiple operations training may be interpreted as inducing coordination of relevant operations rather than the operations themselves. That is, rather than cause the subject to acquire one or more of the specific operations being taught (which then may be used as a basis for generating conserving responses), multiple operations training methods ‘attempt to integrate segregated mental operations’ (p. 344). This interpretation is difficult to countenance. To begin with, it is obvious that the interpretation is sound only if the subjects in the relevant experiments already possessed the trained operations before they were subjected to training. There is only one way to establish this essential premise with any certainty in a conservation training experiment : The subjects must be pretested for both conservation and each of the operations included in the training treatment. If the posttest assessments reveal that the treatment induces conservation in subjects who already possessed the operations and fails to induce conservation in subjects who do not possess the operations, then (and only then) we might conclude that the effectiveness of multiple operations treatments stems from ‘operational coordination’. In the absence of such evidence, however, it is equally reasonable to conclude that the effectiveness of the treatments stems from the inculcation of the operations themselves. Suffice it to say that there is no evidence of this sort in the conservation training literature. Concerning the specific experiments Strauss cites, none of the subject samples was carefully pretested for the operations included in the training experiences. If the coordinative interpretation of multiple operations treatments cannot be accepted, then we are left with only the aforementioned conclusion that this type of training has been ‘markedly successful’. As Strauss states it, this conclusion alleges two things: (a) Multiple operations training per se has been a successful conservation induction technique, and (b) multiple operations training has been considerably more successful than individual operations training. These allegations seem neither safe nor certain to me. Concerning a, I mentioned earlier that Strauss classifies many studies which previous reviewers have viewed as examples of reversibility training as examples of multiple operations training. In fact, all of the multiple operations experiments Strauss cites incorporate reversibility in their training treatments. Reversibility therefore is thoroughly confounded with multiple operations. Given the apparent success of treatments in which only reversibility is trained (cf., above), it is

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quite possible that the ‘markedly successful’ outcomes of the cited experiments are attributable to reversibility training and not to multiple operations training per se. Concerning b, the credibility of this allegation turns to a considerable extent on the previously discussed conclusion that individual operations training has been generally unsuccessful. We have seen that the literature does not support this conclusion. Therefore, we require further evidence to verify b. Explicitly, w/e require studies in which the effects of treatments incorporating single operations are compared factorially with the effects of treatments in which these operations are trained together. Unfortunately, there have been virtually no studies whose designs fulfill this requirement. In all the studies Strauss cites, for example, operations are trained together but not individually. The only study whose design meets the preceding requirement produced findings that are clearly inconsistent with b. Goldschmid (1968, 1971) trained both inversion reversibility and reciprocity reversibility individually, and he also trained them jointly. He found that the inversion-only treatment was more powerful than either the reciprocity-only or inversion-plus-reciprocity treatments. The reciprocityonly and inversion-plus-reciprocity treatments did not differ. A recent experiment by Siegler and Liebert (1972) also merits brief mention in conjunction with b. Siegler and Liebert found that a multiple operations treatment incorporating the operations of addition-subtraction, inversion reversibility, reciprocity reversibility and identity was much less powerful than a simple feedback treatment. Thus, the available findings do not permit either the conclusion that multiple operations treatments per se have been successful or the conclusion that such treatments have been more successful than individual operations treatments. Even if the available evidence did support both conclusions, I do not think that either could be regarded as interesting or as providing nontrivial support for Piaget’s stage hypothesis. Given that individual operations treatments have been successful, multiple operations treatments probably should be too. Similarly, it would not be especially surprising if future studies established that training two or more operations jointly is a more effective method of inducing conservation than training the same operations individually. Individual operations treatments may be viewed as providing subjects with one and only one logical rule with which to generate conserving responses, whereas multiple operations treatments may be viewed as providing at least two such rules. On purely statistical grounds, it seems likely that the frequency of conserving responses should be positively correlated with the number of conserving rules in one’s repertoire. About the only argument against this relationship is that multiple operations training might produce an informational overload. 2.3.

Extinction experiments

Strauss considers attempts to extinguish concrete-operational concepts in the final major section of his review. Although extinction studies of moral and classificatory

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concepts also are dealt with, this section has a single dominant theme: How can we effect a rapprochement between Miller’s (1971a) conclusion that ‘extinction of conservation is ubiquitous, rather easy to obtain’ (p. 347) and the stage-theoretic expectation that the absolute extinction resistance of conservation concepts should be virtually perfect. Predictably, the discrepancy is resolved by suggesting that the theory is correct and Miller is wrong. It must be said that the empirical grounds for this suggestion are extremely thin. Essentially, they consist of accepting the findings of a single early experiment by Smedslund (1961 b) and rejecting the findings of several more recent experiments whose findings are consistent with Miller’s thesis. This choice is difficult to defend. Other reviewers have pointed out that the design of Smedslund’s experiment is fraught with methodological contaminants whose direction indicates that the principal findings may be Type I errors (e.g., cJ, Brainerd and Allen, 1971a, pp. 138-139). Hence, if one were forced to choose between Miller and Strauss’ respective conclusions, one would have to admit that the evidence favors Miller. I do not propose to choose between these two alternatives, however, because the findings of existing conservation extinction experiments are not precisely as either Miller or Strauss portray them. I do not believe these studies show either that it is easy to obtain virtually perfect extinction with all conservation concepts or that it is extremely difficult to extinguish all conservation concepts. I shall advance a third interpretation. It seems reasonable to suppose that conservation concepts will be difSerentialZy resistant to extinction treatments. Explicitly, it seems likely that the resistance of a given conservation concept to a given extinction treatment should depend to a considerable extent upon the ordinal position that concept occupies in the natural emergence hierarchy for conservation concepts. Conservation concepts occupying the earliest ordinal positions should be rather difficult to extinguish, while concepts occupying middle and late positions should be correspondingly less difficult to extinguish. There is a two-fold rationale for this interpretation. First, we know that there is a lag of as much as six years between the emergence of the first and last concrete-operational conservation concepts. In the case of number, quantity and weight conservation, for example, number precedes quantity by roughly two years (e.g., Brainerd and Brainerd, 1972) and quantity in turn precedes weight by roughly two years (e.g., Piaget and Inhelder, 1941). The large temporal gap between number conservation and weight conservation suggests that the latter probably requires much more extensive experiential confirmation than the former. That is, for some reason, number conservation is experienced as more logically necessary than weight conservation. Therefore, number conservation should be more difficult to extinguish via disconfirming experiential data. The same general argument applies to the relationship between number and quantity, on the one hand, and quantity and weight, on the other.

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The second part of the rationale is simpler and more ineluctable. As is the case with many other concrete-operational decalages, some of the earlier concepts in the natural emergence hierarchy for conservation are logically necessary prerequisites for later concepts in the hierarchy (cJ, Flavell, 1972, for other examples). For example, density conservation logically presupposes both weight and volume conservation (Brainerd, 1971; Brainerd and Allen, 1971b). In our preceding example, quantity conservation is a logical prerequisite for weight conservation. It has been observed elsewhere (Brainerd and Allen, 1971a) that a logical prerequisite for a given concept should always be more difficult to extinguish than the concept itself. Only three conservation concepts have been subjected to extinction manipulations : Number, quantity and weight. The findings reported to date are more or less consistent with the view I have just outlined. Wallach and Sprott (1964) attempted to extinguish number conservation in both natural and trained conservers. They reported very high levels of extinction resistance in both groups. There have been several attempts to extinguish naturally acquired and experimentally induced quantity conservation (Brainerd, 1972a; Brison, 1966; Brison and Bereiter, 1967; Sullivan, 1967, 1969), and the consistent finding has been moderate-to-good resistance among both natural and trained conservers. In the most recent and quantitatively precise of these studies, for example, a 53 % rate of resistance was observed for natural conservers, and a 57 % rate of resistance was observed for trained conservers (Brainerd, 1971a). There also have been several attempts to extinguish weight conservation in natural and trained conservers (Hall and Kingsley, 1968; Hall and Simpson, 1968; Kingsley and Hall, 1967; Miller, 1971b, 1973; Miller et al., 1973; Smedslund, 1961b; Smith, 1968). Here, the consistent finding has been poor extinction resistance among both natural and trained conservers. Kingsley and Hall (1967) and Smith (1968) first reported a virtual absence of resistance in both subject groups. Subsequently, Hall and Kingsley (1968) reported 100 % extinction in 16 naturally conserving children and roughly 70% extinction in 64 naturally conserving undergraduates. The former finding was replicated by Hall and Simpson (1968). Both Miller (1971b, 1973) and Strauss (1972; Strauss and Liberman, in press) have criticized these studies on the grounds that their post-extinction questioning formats were not sufficiently probabative to eliminate the possibility of what Miller calls ‘a socially compliant “pseudoextinction”’ (1973, p. 48). In defense of these studies, however, it may be argued that it is equally probable that including leading questions in the post-extinction assessments could produce socially compliant ‘pseudoconservation’. Fortunately, we apparently do not have to choose between these two undesirable methodological possibilities. Miller (1971b, 1973) has re-examined weight conservation extinction in children using assessments designed to eliminate the pseudoextinction criticism and he still finds poor resistance. With naturally conserving 8- and 1 1-year-olds, Miller found no resistance

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on one dependent variable (surprise) and roughly 30 ‘A resistance on a second dependent variable (leading questions). Miller also has re-examined conservation of weight extinction in college students (Miller et al., 1973). On one dependent variable (postfeedback explanations) the rate of resistance was roughly 50 %. On a second dependent variable (proportion of subjects who never gave a nonconserving judgment) the rate of resistance was roughly 60%. In view of the high general intelligence of University of Michigan undergraduates, their correspondingly high levels of scientific sophistication, and the fact that the possibility of communication between subjects existed, this 50 %-60x figure probably may be regarded as an absolute ceiling for weight conservation extinction resistance. One is led to conclude that the rate of resistance in the normal adult population would be many times lower. There is another datum generated by conservation extinction studies to which I should like to draw the reader’s attention in closing. This datum is distinguished primarily by its absolute uninterpretability - which perhaps explains why Strauss and Miller do not dwell on it in their respective reviews. From the perspective of just about any global view of cognitive development that one might care to adopt, from cumulative experiential to stage-theoretic to even maturationist, it seems to follow that trained conservers should be much less resistant to extinction than natural conservers. However, investigators have failed repeatedly to verify this seemingly trivial prediction. Smedslund (1961b) is the only investigator to find support for it and, unfortunately, his findings may be Type I errors (I$, Brainerd and Allen, 1971a, pp. 138-l 39). No one, least of all the writer, has yet suggested a satisfactory methodological or theoretical explanation for these surprising, but nevertheless replicable, findings. In the long run, I prefer to believe that more refined experiments will reveal differences between trained and natural conservers in the predicted direction. For now, however, I am compelled to note that trained and natural conservers have not been shown to be differentially resistant to extinction and that this fact appears blatantly inconsistent with a stage view of cognitive development. Summary

To sum up with reference to Strauss’ three categories of stage-related training experiments, the following seven statements appear to be consistent with the currently available data : 1. Training treatments which introduce disequilibrium into the cognitive system from external sources have proved a fruitful means of inducing concrete-operational concepts. The evidence is most extensive for conservation, but some evidence pertaining to class concepts and relational concepts also has been reported. 2. Subjects who evidence a given concrete-operational concept on the pretests tend

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to be more susceptible to training experiences designed to induce that concept than subjects who do not evidence the concept on the pretests. This fact, in and of itself, permits no further conclusions about ‘structural mixture’ and training susceptibility. 3. If we have two concrete-operational concepts A and B such that A invariably precedes B during the course of normal cognitive growth, A probably will prove easier to train than B in subjects who possess neither concept. 4. Training treatments that may be interpreted as focusing narrowly on a single conservation-relevant operation (or rule) have successfully induced conservation concepts. There are substantial amounts of supportive data in the specific case of inversion reversibility. The data are less extensive but nevertheless supportive in the case of addition-subtraction, identity and reciprocity reversibility. 5. Because multiple operations training is confounded with inversion training in the literature and because multiple operations training has not been compared factorially with individual operations to any great extent, there is no definitive evidence that multiple operations treatments will induce conservation. In view of statement 4, however, it seems reasonable to suppose that multiple operations training eventually will prove successful also. 6. The resistance of conservation concepts to extinction treatments is neither universally low nor universally high. Instead, resistance appears to vary as a function of the order of emergence of conservation concepts. 7. To date, appreciable differences in the extinction resistance of trained and natural conservers have not been observed. With the possible exception of statement 5, each of the preceding statements contradicts one or more of the evidentiary conclusions Strauss advances. At the beginning of this paper, we observed that Strauss’ claim that the neo-Piagetian training literature provides support for a stage view of cognitive development turns on the validity of these evidentiary conclusions. I therefore conclude that no support for a stage view of cognitive development has been derived from the neo-Piagetian training literature. REFERENCES Ahr, P. R., and Youniss, J. (1970) Reasons for failure on the class inclusion problem. Child Devel., 41, 131-143.

Bandura, A. (1969) Social-learning theory of identification processes. In D. A. Goslin (Ed.), Handbook of socialization theory and research. Chicago, Rand McNally. Bearison, D. J. (1969) The role of measurement operations in the acquisition of conservation. Devel. Psychol., 1, 653-660. Beilin, H. (1965) Learning and operational

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convergence in logical thought development. J. exp. Child Psychol., 2, 317-339. (1969) Stimulus and cognitive transformation in conservation. In D. Elkind and J. H. Flavell (Eds.), Studies in cognitive development. New York, Oxford University Press. (1971a) Developmental stages and developmental processes. In D. R. Green, M. P. Ford and G. B. Flamer (Eds.), Measurement and Piaget. New York,

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McGraw-Hill. (1971b) The training and acquisition of logical operations. In M. F. Rosskopf, L. P. Steffe and S. Taback (Eds.), Piagetian cognitive developmental research and mathematical education. Washington, National Council of Teachers of Mathematics. Braine, M. D. S. (1959) The ontogeny of certain logical operations: Piaget’s formulation examined by nonverbal methods. Psychol. Mono., 73 (5), (Whole No. 475). __ (1962) Piaget on reasoning: A methodological critique and alternative proposals. In W. Kessen and C. Kuhlman (Eds.), Thought in the young child. Mono. sot. Res. child Devel., 27 (2, Whole NO. 83). __ (1964) Development of a grasp of transitivity of length: A reply to Smedslund. Child Devel., 35, 799-810. Brainerd, C. J. (1971) The development of the proportionality scheme in children and adolescents. Devel. Psycho/., 5, 469476. (1972a) Reinforcement and reversibility in quantity conservation acquisition. Psychon. Sci., 27, 114-l 16. (1972b) The age-stage issue in conservation acquisition. Psychon. Sci., 29, 115117. -(1972~) Structures of thought in middlechildhood: Recent research on Piaget’s concrete-operational groupements. Paper read at the Third Annual Conference on Structural Learning, Philadelphia, March. April. (1973a) The stage problem in behavioral development. Unpublished manuscript, University of Alberta. (1973b) Judgments and explanations as criteria for the presence of cognitive structures. Psychol. Bull., 79, 172-179. (1973~) Order of acquisition of transitivity, conservation, and class inclusion of length and weight. Devel. Psychol., 8, 105-116. (in press, a) Postmortem on judgments, and Piagetian cognitive explanations, structures. Psychol. Bull., 81. __ (in press, b) Training and transfer of transitivity, conservation, and class inclusion of length. Child Devel., 45.

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and Allen, T. W. (1971a) Experimental inductions of the conservation of ‘firstorder’ quantitative invariants. Psychal. Bull., 75, 128-144. and Allen, T. W. (1971b) Training and transfer of density conservation: Effects of feedback and consecutive similar stimuli. Child Devel., 42, 693-704. and Brainerd, S. H. (1972) Order of acquisition of number and liquid quantity conservation, Child Devel., 43, 1401-1406. and Hooper, F. H. (1974) A methodological review of developmental studies of identity and equivalence conservation. Unpublished manuscript, University of Alberta. and Kaszor, P. (in press) An analysis of two proposed sources of error on the class inclusion problem. Devel. Psychol., 10. Brison, D. W. (1966) Acceleration of conservation of substance, J. genet. Psychol., 109, 31 l-322. and Bereiter, C. (1967) Acquisition of conservation of substance in normal, retarded, and gifted children. In D. W. Brison and E. V. Sullivan (Eds.), Recent research on the acquisition of conservation of substance. Toronto, The Ontario Institute for Studies in Education. Bruner, J. S. (1964) The course of cognitive growth, Amer. Psychol., 19, l-15. Olver, R. R., and Greenfield, P. M (1966) Studies in cognitive growth. New York, Wiley. Bucher, B., and Schneider, R. E. (1973) Acquisition and generalization of conservation by pre-schoolers, using operant training. J. exp. child Psychol., 15, 187Clou:,pe”,: R. (1973) Unpublished doctoral dissertation, McGill University. Dagenais, Y. (1973) Analyse de la coherence operatoire entre les groupements d’addition des classes, de multiplication des classes et d’addition des relations asymetriques. Unpublished doctoral dissertation, Universite de Montreal. Elkind, D. (1967) Piaget’s conservation probblems. Child Devel., 38, 15-27. Feigenbaum, K. D., and Sulkin, H. (1964) Piaget’s problem of conservation of dis-

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continuous quantities: A teaching experience. J. genet PsychoI., 105, 91-97. Figurelli, J. C., and Keller, H. R. (1972) The effects of training and socio-economic class upon the acquisition of conservation concepts. Child Devel., 43, 293-298. Flavell, J. H. (1971) Stage-related properties of cognitive development. Cog. Psychol., 2,421-453. (1972) An analysis of cognitive-developmental sequences. Genet. Psychol. Mono., 86,279-350. and Wohlwill, J. F. (1969) Formal and functional aspects of cognitive development. In D. Elkind and J.H. Flavell (Eds.), Studies in cognitive development. New York, Oxford University Press. Gelman, R. (1969) Conservation acquisition: A problem of learning to attend to relevant attributes. J. exp. child Psychol., 7, 167-187. Glaser, R. and Resnick, L. B. (1972) Instructional psychology. In P. H. Mussen and M. R. Rosenzweig (Eds.), Annual review of psychology. Palo Alto, Annual Reviews, Inc. Golds&mid, M. L. (1968) Role of experience in the acquisition of conservation. Amer. Psychol. Assoc. Proc., 76, 361-362. (1971) The role of experience in the rate and sequence of cognitive development. In D. R. Green, M. P. Ford and G. B. Flamer (Eds.), Measurement and Piaget. New York, McGraw-Hill. Gruen, G. E. (1965) Experiences affecting the development of number concepts in children. Child Devel., 36, 963-979. (1966) Note on conservation: Methodological and definitional considerations. Child Devel., 37, 977-983. and Vore, D. A. (1972) Development of conservation in normal and retarded children. Devel. Psychol., 6, 146-157. Halford, G. S. (1970) A theory of the acquisition of conservation. Psychol. Rev., 77, 302-316. Hall, V. C., and Kingsley, R. (1968) Conservation and equilibration theory. J. genet. Psycho/., 113, 195-213. and Simpson, G. J. (1968) Factors influencing extinction of weight conservation. Merrill-Palmer Q., 14, 197-210.

Hamel, B. R. (1971) On the conservation of liquids. Hum. Devel., 14, 39-46. and Riksen, B. 0. M. (1973) Identity, reversibility, verbal rule instruction, and conservation. Devel. Psychol., 9, 66-72. Van der Veer, M. A. A., and Westerhof, R. (1972) Identity, language-activation training and conservation. Brit. J. educ. Psychol., 42, 186-191., Hatano, G. A. (1971) A developmental approach to concept formation: A review of neo-Piagetian learning experiments. Dokkyo Univer. Bull. Lib, Arts. Ed., 5, 59-76. and Ito, Y. (1966) The acquisition of conservation of area in second graders. Jap. J. Psychol. 37, 185-194. and Suga, Y. (1969) Equilibration and external reinforcement in the acquisition of number conservation. Jap. Psychol. Res., 11, 17-31. Hooper, F. H., Goldman, J. A., Strock, P. A., and Burke, A. M. (1971) Stage sequence and correspondence in Piagetian theory : A review of the middle-childhood period. Research relating to children. Bulletin 28. Washington, U.S. Printing Office. and Klausmeier, H. J. (1973) Longitudinal assessment of children’s cognitive development and concept learning. Working paper No. 113, University of Wisconsin Research and Development Center for Cognitive Learning. Inagaki, K. (1970) The effect of cognitive motivation on receiving and gathering of information. Jup. J. educ. Psychof., 18, 14-25. and Hatano, G. (1968) Motivational influence on epistemic observation. Jup. J. educ. Psychol., 16, 191-202. and Hatano, G. (1972) The effect of cognitive motivation aroused by positive infirming instances. Jup. J. educ. Psychol., 20. Inhelder, B., and Piaget, J. (1964) The euvjy growth of logic in the child. London, Routledge and Kegan Paul. and Sinclair, H. (1969) Learning cognitive structures. In P. Mussen, J. Langer and M. Covington (Eds.), Trends and issues in developmental psychology. New York, Holt, Rinehart, and Winston.

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Kessen, W. (1962) ‘Stage’ and ‘structure’ in the study of children. In W. Kessen and C. Kuhlman (Eds.), Thought in the young child. Mono. Sot. Res. child Devel., 28 (2, Whole No. 83). Kingsley, R. C. and Hall, V. C. (1967) Training of conservation through the use of learning sets. Child Devel., 39, 1013-1062. Kofsky, E. (1966) A scalogram study of classificatory development. child Devel., 37, 191-204. Miller, S. A. (1971a) Extinction of conservation: A methodological and theoretical analysis. Merrill-Palmer Q., 17, 319-334. (1971b) Contradiction, surprise, and cognitive change: The effects of disconfirmation of belief on conservers and nonconservers. Unpublished doctoral dissertation, University of Minnesota. Also in (1973) J. exp. child Psychol., 1547-62. Schwartz, L. C., and Stewart, C. (1973) An attempt to extinguish conservation of weight in college students. Devel. Psycho/., 8, 316. Murray, F. B. (1972) The acquisition of conservation through social interaction. Devel. Psychol., 6, l-6. and Johnson, P. E. (1969) Reversibility in nonconservation of weight. Psychon. Sci., 16, 285-286. Overbeck, C., and Schwartz, M. (1970) Training in conservation of weight. J. exp. child Psychol., 9, 253-264. Piaget, J. (1956) Les stades du developpement intellectuel de l’enfant et de l’adolescent. In P. Osterrieth et al. (Eds.), Le probkme des stades en psychologie de I’enfant. Paris, Presses Universitaires de France. (1960) The general problems of the psychobiological development of the child. In J. M. Tanner and B. Inhelder (Eds.), Discussions on child development. Vol. 4., London, Tavistock. (1968) On the development of memory and identity. Barre, Mass., Clark University Press. (1973) The child and reality, New York, Grossman. and Inhelder, B. (1941) Le diveloppement des quantitts physiques. Neuchatel and Paris, Delachaux and Niestle. Pinard, A., and Laurendeau, M. (1969) ‘Stage’

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in Piaget’s cognitive-developmental theory: Exegesis of a concept. In D. Elkind and J. H. Flavell (Eds.), Studies in cognitive development. New York, Oxford University Press. Reese, H. W., and Schack, M. L. (in press) Comment on Brainerd’s criteria for cognitive structures. Psychol. Bull., 81. Roll, S. (1970) Reversibility training and stimulus desirability as factors in conservation of number. Child Eevel., 41, 501507. Rosenthal, T. L., and Zimmerman, B. J. (1972) Modeling by exemplication and instruction in conservation. Devel. Psychol., 6, 392-401. Rothenberg, B. B., and Orost, J. H. (1969) The training of conservation of number in young children. Child Devel., 40, 707726. Schnall, M., Alter, E., Swanlund, T., and Schweitzer, T. (1972) A sensory motor context affecting performance in a conservation task: A closer analogue of reversibility than empirical return. Child Devel., 43, 1012-1023. Siegler, R. S., and Liebert, R. M. (1972) Effects of presenting relevant rules and complete feedback on the conservation of liquid quantity. Devel. Psychol., 7, 133-138. Silverman, I. W., and Geiringer, E. (1973) Dyadic interaction and conservation induction: A test of Piaget’s equilibration model. Child Devel., 44, 815-820. Smedslund, J. (1961a) The acquisition of conservation of substance and weight in children. I. Introduction. Scan. J. Psychol., 2, 11-20. (1961b) The acquisition of conservation of substance and weight in children. II. Extinction of conservation of weight acquired ‘normally’ and by means of empirical controls on a balance scale. Scan. J. Psychol., 2, 85-87. (1961~) The acquisition of conservation of substance and weight in children. V. Practice in contlict situations without reinforcement. Scan. J. Psychol., 2, 156-160. (1963) The development of concrete transitivity of length in children. Child Devel., 34, 389-405. (1965) The development of transitivity

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of length: A comment on Braine’s reply. Child Devel., 36, 517-580. (1969) Psychological diagnostics. Psychol. Bull., 71, 234-248. Smith, I. D. (1968) The effects of training procedures on the acquisition of conservation of weight. Child Devel., 39, 515526. Strauss, S. (1972) Inducing cognitive development and learning: A review of shortterm training experiments I. The organismic-developmental approach. Cog., 1, 329-357. -and Liberman, D. (in press) The empirical violation of conservation laws and its relation to structural change. J. exp. child Psychol., 18. Suga, T. (1966), Thinking. Ann. Rev. Jag. fsychol., 5, 61-80. Sullivan, E. V. (1967) Acquisition of conservation of substance through film modeling techniques. In D. W. Brison and E. V. Sullivan (Eds.), Recent research on the acquisition of conservation of substance. Toronto, Ontario Institute for Studies in Education. (1969) Transition problems in conservation research. J. genet. Psycho!., 115, 4154. Trabasso, T. (1968) Pay attention. Psychof.

Toduy, 2(5), 30-36. Wallach, L. and Sprott, R. L (1964) Inducing number conservation in children. Child Devel., 35, 1057-1071. Wall, A. J., and Anderson, L. (1967) Number conservation: The roles of reversibility, addition/subtraction and misleading perceptual cues. Child Devel., 38, 425-442. Waghom, L., and Sullivan, E. V. (1970) The exploration of transition rules in conservation of quantity (substance) using film mediated modeling. Acra Psychol., 32, 65-80. Wason, P. C. (1966) Reasoning. In B. Foss (Eds.) New horizons in psychology. Harmondsworth, England, Penguin Books. Weinreb, N., and Brainerd, C. J. (1973) A developmental study of Piaget’s groupement model of the emergence of speed and time concepts. Unpublished manuscript, University of Alberta. Winer, G. A. (1968) Induced set and acquisition of number conservation. Child Devel., 39, 195-205. Wohlwill, J. F., and Lowe, R. C. (1962) An experimental analysis of the development of the conservation of number. Child Devel., 33, 153-167.

5

A generative

transformational child language

model for acquisition:

A discussion of L. Bloom, Language development: Form and function in emerging grammars A. SCHAERLAEKENS University

of Leuven

development: Form and function in emerging grammars (M.I.T. Press, 1970), Bloom does not merely criticize the Pivot-open model but introduces her own transformational model for three children she examined thoroughly. Since her starting point is the primary importance of a contextual interpretation of the first utterances of children, this book offers consistently and in a precise way the circumstances in which utterances are produced for all those recorded. According to Bloom, it is clear that the child masters a number of fundamental grammatical relations, that is, that he can draw a grammatical relationship of subjectverb or of subject-object, for example. If one adopts such an interpretation, it becomes clear that different hierarchical structures can be present in the two-word sentence. A generative transformational model can describe them by means of a number of phrase structure rules and can record the regularities in the surface structure. An examination of the phrase structure rules which Bloom constructed for Kathryn immediately reveals that this model is rather half-hearted; it contains two simultaneous rules, a normal phrase structure rule and a ‘pivot-rule’. Utterances such as ‘this necklace’, ‘this book’, ‘this cold’ and ‘nother book’, ‘nother tap’ could not be described with the normal phrase structure rules. This must certainly be considered a deviation from the traditional T/G-model, but Bloom believes that such a deviation is possible at a certain stage of child language. In addition to these phrase structure rules, there are three transformation rules of which two are optional place transformations, and one is an obligatory reduction transformation. The phrase structure rules can produce three-word sentences, but these do not fit within Kathryn’s grammar at this stage. The following remarks have to be made with regard to this transformational generative scheme. A. Insofar as Bloom’s findings in relation to Kathryn are concerned, one must admit that the model remains ambiguous in the sense that the concept of the pivot cannot be totally eliminated from it. For Kathryn, the pivots are ‘hi’, ‘that’,‘this’, In Language

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‘more’ and ‘nother’. Bloom argues that there can be no objection to the inclusion of a word class of pivots along with the word classes of verb, nouns, etc. It is certainly possible that child language at certain stages of development exhibits such a deviation from the adult model. The inconsistencies which were present in the initial pivotopen grammar, however, have been reintroduced into the T/G-model. Bloom (pp. 4142) provides a phrase structure rule, S, + Pivot + Noun, even though this rule must also describe such expressions as ‘this rides’ - ‘this turn’ - ‘this dirty’ - ‘that’s cold’. It is not plausible to consider the words in these sentences as nouns. On the other hand, the pivot ‘more’ appears, in the data of Bloom’s study, only in the construction more+noun. Consequently, the criticism that the pivot model supplies insufficient differentiation of word classes also applies to and reappears in the T/G-model. It is thus necessary to ask why a double phrase structure consisting in the simultaneous occurrence of both a normal phrase structure rule and a pivot rule is adopted in the T/G-scheme. Responsibility can most probably be attributed to the fact that it would be too complex to integrate sentences representing a traditional pivot structure with a standard transformational generative model. The reason tar this is that one would have to derive a very complex set of phrase structure rules to which an impossibly large number of reduction transformations would have to be applied. The objection to this usage of reduction transformations is that one must attribute a more complex structure to the grammar than is available and than appears in sentences without pivots. It will be demonstrated that the T/G-model acts in this way to a certain extent. However, this model reintroduces the pivot rule because it is believed that its absence would necessitate too many reductions and would impose an articulated adult model upon child language, with the consequence that one would encounter the same pitfalls which were attributed to linguists of the pre-transformational era. Through its lack of interpretation and differentiation of hierarchical structure, the pivot-open grammar was able to avoid the problem of reduction transformations. Possibly for that reason, moreover, the pivot concept has been reintroduced into the T/G-model. It is clear, however, that this adoption does not provide a solution to the problem at hand but that it renders the T/G-model vulnerable to the same basic criticism made of the initial pivot-open model. B. At this point it is necessary to consider the fundamental question: To what end is it necessary to construct a grammar of child language? As such, a grammar seeks to describe the child’s language at a certain stage of development, and two possible aims for the employment of the T/G-model exist: 1. The T/G-model is an attempt to express the intuitions of the adult concerning the characteristics of child grammar and seeks to define these characteristics in a logical manner. What happens in this case is that one describes a logical insight from an adult’s point of view into the performance of the child. This description of language

A generative tranTformationa1 model for child language acqutsztton

3 13

lays no claim to reflecting psychological reality, and it follows as a matter of course that one transposes without reservation the categories of adult grammar onto the linguistic performance of the child. 2. The T/G-model seeks to describe the competence of the child himself; that is, it attempts to reveal the system which forms the basis of the child’s performance. One wants to describe the linguistic insight the child itself possesses, and, consequently, one attributes a certain psychological reality to this competence. It appears that this double vision is applicable to the description of the language used by adults. Is such a grammar a purely formal logical system, or does it correspond to a psychological reality? In other words, is there any evidence which supports the claim that transformational rules represent a psychological reality? Does one really utilize transformations, or are these rules only formulas employed to arrive at a formalized systematization of language? This controversy is still very much alive, especially in psycholinguistics. There are, however, other authors (e.g., Chomsky, 1965, pp. 8-9) who claim no interest in this psychological correlation and who assert that a T/G-model only attempts to construct a model which adequately explains language as such. Even though one can depend on a definite approach towards this problem insofar as adult grammars are concerned, it is not always so when the T/G-model relates to child language. McNeil1 (1970, p. 145) claims clearly that: ‘A theory of competence is also a psychological theory.’ From this, it may be concluded that he seeks to describe a psychological reality with the T/G-model, and that consequently he has adopted the second of the two possibilities described above. But most writers at the outset of their work stress the importance of the distinction between competence and performance. By this means they try to disengage themselves from the pre-transformational approach to child language but remain mysteriously silent about what this competence means. Although they pretend that the competence of the child himself is meant, they give no further explanation. An example of this inconsistency is to be found in Bloom. She states clearly in her introduction that ‘the underlying structure is abstract in the sense that it represents a construct that is intrinsic to the sentence it represents but actually ‘exists’ only in the theoretical linguistic account of the sentence’. This does not deter her however, from presenting an entire chapter of conclusions concerning the strategies employed by the child in learning language based on T/Gmodels constructed in precisely this fashion. Without any further consideration, she then discusses the psychological competence of the child itself. When one wants to arrive at a critical evaluation of the T/G-model, two approaches exist, each coinciding with one of the two possible aims of the T/G-model mentioned above : 1. If one selects the first, one pretends to describe the linguistic performance of children by means of a generally accepted system, but nothing more. In that case, the

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ambiguity which arises from the reintroduction of the pivot class has to be eliminated. The model must be further developed so that it can be formulated in terms of a number of phrase structure rules, from which the term pivot has been deleted. 2. Although most psycholinguists do not explicitly exclude themselves from position 1, they in fact attempt to describe the language capacity of the child himself, i.e., a psychological reality, and consequently actually adhere to position 2. In this case, a T/G-model as constructed by Bloom raises a number of objections as dealt with below. C. In spite of her semantic approach, Bloom defines grammatical relations in configurational terms. This leads necessarily to the assumption of extensive covert structures for which there is little direct evidence. In consequence, a reduction transformation is required for the majority of the sentences derived from her data. This requirement implies a certain dependence on adult grammar, as the more complex sentences of the adult language appear in the performance of the child in a reduced state. From the perspective of a developmental grammar it can be asked whether it is logical and justified to assume that this competence is derived from a more complex model which is always connected with performance by means of a reduction transformation. An example will clarify this point. In a two-word-sentence such as ‘mommy chair’ with the contextual meaning ‘mommy is sitting on the chair’, a positional relationship is expressed by two nouns. It would then be possible to describe the competence of the child by its ability to express a positional relationship using two nouns. The T/Gmodel represents such an expression in the following scheme? S -+ (NPGVP), where NP + N VP + Verb + NP NP+N After the application of a reduction transformation to this scheme, only a noun remains from the complete VP. It seems that a complicated explanation is being sought for a simple phenomenon. There is no reason to assume that the child, during its development, would first apply an intricate transformational rule and only later apply a simple phrase structure rule. From the data of developmental grammar, it is apparent that the child is first capable of expressing such a simple locative relationship as ‘mommy chair’. Only much later do sentences of the type subject + verb + adverb of place occur. There is no evidence which supports the possibility of movement in the opposite direction. From data derived from the child itself, it appears that 1. The symbol $ represents the possibilities of choosing either NP or VP alone.

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‘mommy chair > ‘mommy is sitting on the chair’.2 The T/G-grammar contends that the opposite is true : ‘mommy is sitting on the chair’ + ‘mommy chair’. This could be a reasonable conclusion, but if one considers the description of competence as being correlated to a psychological reality in the child, the T/G-model conclusion is no longer justified. If the T/G-model correctly represents child language, a more developed model appearing in the simplified form only after the transformations had been completed would already be present in the child. One may apply the same criticism to this line of reasoning as Chomsky has applied to Skinner’s presumptions, namely, that a model exists for which there is no evidence in the language itself. One might accept this model, however, because it is fairly simple and straightforward and because it is consistent with the preconceived, general framework in which one thinks, in this case the T/G-model. This model tries to describe the entire child grammar through the employment of a limited number of phrasestructure rules. A number of transformational rules must then be employed to explain the diversity in the surface structure. Even if this model might be applicable to adult grammar, its a priori application to child grammar is methodologically a very daring jump. A generalization of the transformational model to child grammar is certainly preposterous at this time. There are some arguments, on the contrary, which contend that a child does not employ transformations, and some evidence supporting this contention is provided by the argument presented here. Some linguists have recently maintained that the simplicity of the two-word-grammar sentences render unconvincing the notion that transformations are part of such grammars. Slobin (197 1, p. 51) comments on this on the basis of studies concerning the development of the negation transformation: ‘Because his sentences are so simple, he does not need to use the complex transformational apparatus of adult speech . . . In the course of his development he has more and more complicated things to say, and must figure out ways of doing so. At first he isn’t very good at it, and he invents rather clumsy grammars. Eventually, it seems, these clumsy grammars break down and the child is forced to invent something like a transformational grammar for the sake of efficiency.’ In a recent study (1971, p. 317) Van der Geest claims that the child speaks initially without transformations because the meaning of the lexical items automatically indicates the syntactic relation which is implied. Consequently he refers to the period of the two-word-sentence as semantic speech. In his view the child only later feels the need to eliminate the contextual ambiguity of his speech and is less and less contextually oriented. Only then can the label syntactic speech be applied. For the time being, it is impossible to ascribe any psychological reality to the concept of transformation. 2. The symbol into’.

> represents

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Even from a linguistic point of view, the need of transformations in early childhood is still under discussion. As long as transformations at this stage of the child’s language development have not yet been proven a reality, one must conclude for yet another reason that it is unjustified to presume that a child reduces a very complex competence to a more primitive performance through transformations. This does indeed contradict some of the conclusions of developmental psychology. Piaget and Inhelder (1968, pp. 16-17) maintain that the child’s concepts of number and three-dimensional space are changed from the acquisition of a series of uncoordinated discoveries to a long progressive assimilation of the entire system in which these two concepts are structured. Their description is as follows: ‘To start with spatio-temporal structures, one may observe at the beginning that there exists no unique space nor does there exist a temporal order which encompasses the objects and the events . . . All that is supplied is a mixture of heterogeneous spaces . . . Progressively these spaces are later coordinated, but these coordinations remain partial for a long time . . .‘. Metzger (1956) explains that, within the Gestalt theory, the genesis of the Gestalt does not progress uniformly from the whole to the parts, but that the genesis may also move from the parts to the more complex whole. In the light of these findings of developmental psychology, it is even more probable that the child will master the grammatical relations in an at first uncoordinated fashion. The relations which do occur are positional relations between two nouns, subject-verb relations and objectverb relations. Only after perceiving these relationships can the child perceive the unified structure of subject-verb-adverb of place. It is, consequently, quite possible to adopt the position that in establishing a child grammar one is looking for an adequate formal logical model which can explain the child’s performance and to which no psychological reality is attributed. Bloom, however, does not do this. Instead she takes a somewhat ambiguous position, which in the end attributes psychological reality to the T/G-model. Language development: Form andfunction in emerging grammars does not solve this ambiguity.

REFERENCES Chomsky, N. (1965) Aspects of the theory of syntax. Cambridge, Mass., M.I.T. Press. McNeill, D. (1970) The acquisition of kmguage: The study of developmental psycholinguistics. New York, Harper & Row. Metzger, W. (1958) Die Entwicklung der Gestaltauffassung in der Zeit der Schulreife.

Westermans Padagogische Beitrage VIII. Piaget, J., and Inhelder, B. (1968) La psychologie de l’enfant. Paris, Presse Uni-

versitaires de France. Slobin, D. (1971) Psycholinguistics. Glenview, Ill., and London, Scott, Foresman. Van der Geest, A. J. N. (1971) De zinstrukturen die kinderen gebruiken: Een bespreking van P. Menyuk, Sentences children use. In Nederlands Tgdschrift voor de Psychologie 7, 317.

en haar Grensgebieden,