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A note on the “word-order problem” in agrammatism
BRAIN
AND
LANGUAGE
20, 155-165 (1983)
NOTES AND DISCUSSION A Note on the “Word-Order Problem” in Agrammatism DAVID Montreal
CAPLAN
Neurological
Institute
This brief note has two parts. First, it presents an analysis of the ability of English agrammatic patients to assign the thematic roles of agent, instrument, theme, and locative to noun phrases in active and passive sentences and prepositional phrases. Data regarding this ability have been presented by Schwartz, Saffran, and Marin (Brain and Language, 10, 149-262 (1980)) regarding comprehension, and by Saffran, Schwartz, and Marin (Brain and Language, 10,263280 (1980)) regarding production. These authors claim their data show that English agrammatic aphasics do not map “word order” onto thematic information. However, a very simple set of principles accounts for all their results, including results which are discrepant in their treatment, but requires that English agrammatics assign thematic roles to NPs in part by virtue of the position of an NP in a sentence or a phrase. In the second part of this note, several issues raised by this re-analysis are briefly discussed.
I Saffran et al., (1980) presented data regarding the order of nouns around verbs in sentences describing simple pictures of actions, produced by five agrammatic patients. The authors note a strong effect of animacy upon the position of the nouns around the verbs. When an animate noun acts upon an inanimate noun (as in a picture of a boy hitting a ball), the resulting sentence almost always has the animate noun first-that is, before the verb-while when an animate noun acts upon another animate noun (as in a picture of a boy pushing a girl), the animate noun agent precedes the verb in about a third of storable sentences. The authors suggest that thematic roles are not mapped onto word-order positions, and that animacy determines the position of nouns around verbs. A I have benefited in the preparation of this note from discussions with Mary-Louise Kean, John Goldsmith, and Remu Job. Any remaining errors in this analysis or in its interpretation are solely my responsibility. Send requests for reprints to Dr. David Caplan, Department of Neurology, Montreal Neurological Institute, 3801 University, Montreal, Quebec, Canada H3A 2B4. 155
0093-934X/83 $3.00 Copyright 0 1983 by Academic Press. Inc. All rights of reproduction in any form reserved.
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NOTES AND DISCUSSION
similar set of results occurred when the experiment was replicated using a sentence anagram rather than a verbal production task. There were, however, some data which did not entirely correspond to the notion that animacy alone determined word order. When two inanimate nouns appeared in a picture (as in a picture of a boat pulling a truck), the noun depicted as instrument (in this case “the boat”) was produced before the verb virtually all the time. Furthermore, when an inanimate noun was acting upon an animate noun (as in a picture of a ball hitting a boy), the inanimate noun preceded the animate noun about half the time, with the animate noun preceding the inanimate noun the other half of the time. If animacy alone determines word order of nouns around verbs, one should find that the inanimate/inanimate pairs were treated like the animate/animate pairs (either noun appearing first), while the inanimate/animate pairs should have shown consistent reversals. The authors mention these problems, and conclude that a more general factor, termed “salience” or “potency” accounts for these orderings. One feature of the semantics of the words in question which does not enter into potency or salience, however, is knowledge of the thematic role played by the word involved, according to the authors. They specifically claim that such knowledge is not available to agrammatic patients, who, they say, lack the linguistic concept of thematic relations. There is a quite simple set of rules which does account for the pattern of data, however, and which requires that we assume that the patients know that language encodes thematic relations, and that lexical items can be assigned thematic roles. The rules are the following: 1. Assume the patient is producing sentences in the active voice. 2. Assume that the patient tends to put animate nouns before the verb. 3. Assume the patient tends to put nouns bearing the thematic role of agent or instrument before the verb. Principles 2 and 3 assume that the patient knows which words are animate and that he can assign thematic roles to items in a picture and then assign those roles to words. Principles 1 and 2 are accepted by Saffran and colleagues (1980). The first prerequisite underlying 3-the semantic parsing of pictures into thematic terms by these patients-is also accepted by these authors. What is at issue is the second prerequisite for assumption 3-that thematic information derived from the analysis of a picture can be mapped onto words. Assuming these principles are additive in their effects, they account for the production data in a straightforward way. In the animate-agent/ inanimate-theme cases, 2 and 3 both dictate the animate agent will go first. It does. In the animate-agent/animate-theme cases, 2 and 3 will dictate that the animate agent goes first, but 2 will also dictate that the animate theme go first (because of its animacy). The animate agent goes first two-thirds of the time; the animate theme goes first one-third of the time. The two-to-one ratio of which noun goes first exactly reflects the
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additive effects of each of these principles upon word order. In the inanimate-instrument/animate-theme cases, principle 2 dictates that the animate theme go first, and principle 3 dictates that the inanimate-instrument go first; the results are a 50-50 split, which is the case in the data. Finally, in the inanimate-instrument/inanimate-theme cases, only principle 3 applies, putting the inanimate instrument first-such is indeed the case. For the production of locative phrases, the data are that when the two nouns represented in a picture are both inanimate, the inanimate locative noun goes after the preposition about two-thirds of the time, and when the picture represents an animate noun in relation to an inanimate locative noun, the animate noun always precedes the preposition. That is, for pictures showing a pencil in a sink, agrammatics put “the pencil” first about two-thirds of the time and “the sink” first about one-third; for pictures of a bird in a cage, they put “the bird” first almost all the time. The principles which seem to be in operation are: 4. Assume the patient is producing forms of the sort: N Prep N; 5. Assume the patient puts inanimate nouns after the preposition; 6. Assume the patient puts locative nouns after the preposition. Then the data again follow naturally. In the inanimate-themeiinanimatelocative cases, principles 5 and 6 will both affect the inanimate-locative noun, and principle 5 will affect the inanimate theme. As in the sentence cases with animate-agent/animate-theme nouns, we would expect a twothirds/one-third split of responses, which is what occurs. In the animatetheme/inanimate-locative cases, only principle 6 applies, and we get the correct order of words, as observed. The data regarding comprehension provided by these same authors (Schwartz et al., 1980) are also accounted for by principles of exactly the same type. First consider what their patients did in the way of understanding semantically reversible simple active and passive declarative transitive sentences in which all nouns are animate. The authors do not give actual scores, but these are recoverable (or very nearly--I may have misread the exact scores in their Fig. 1 by one or two errors, which would not substantially change the analysis). As a group, the patients produced the correct word order in 75 of 100 active sentences, and in 68 of 100 passive sentences. Suppose the operative principles are: 7. The patient recognizes the voice of the sentence. 8. In the active, assign the noun before the verb as the agent. 9. In the active, assign an animate noun as agent. This strategy will produce a situation where two factors combine to assign agency to animate nouns preceding verbs, and one factor assigns agency to an animate noun following the verb. The results (a three-fourths/onefourth split) are very close to this pattern. Now, consider the following principles for the passive. Principle 7 still applies, and we add:
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DISCUSSION
10. In the passive, assign an animate noun as agent (same as principle 9). 11. In the passive, assign the noun following the verb as the agent. Again, a two-thirds/one-third split of responses is predicted, as is observed. Notice that, except for assigning agency to a post verbal noun in the passive, these principles are exactly the same as those needed for the production data. All that we are adding here is the assumption that the patient recognizes, but not use, the passive form (which is a very reasonable assumption), and that when he recognizes the passive form, he assigns agency to the postverbal rather than the preverbal noun (which is essentially the most expected consequence of “recognizing” the passive form). The authors also report comprehension data for locative constructions. In these cases, only inanimate objects (drawings of circles and squares) were used. Again, I had to estimate the actual error scores from their Fig. 3, but my estimates are certainly accurate enough to support the analysis. Subtracting out lexical errors according to the authors’ Model 2, (which they use themselves), there were 103 correct responses and 91 reversals out of 240 sentences. We account for this pattern by: 12. In a locative construction, an inanimate noun is locative. Here, then, is the only place so far where animacy alone determines thematic role. However, if we make a different assumption about lexical errors-the authors’ Model 3-we get a somewhat different pattern. In this case, there are 114 correct and 91 reversed selections of pictures in these locative phrases-a split close to two-thirds/one-third. If this is the right way to handle lexical errors, we would account for the data by principle 12, above, and principle 13: 13. In a locative construction, the noun after the preposition is locative. In combination, these two principles assign two factors to put the “right” noun after the preposition, and only one to put the “wrong” noun after the proposition-as the data roughly suggest. Principles 12 and 13 are quite similar to 5 and 6. Finally, Schwartz et al. (1980) look at a situation in which line drawings of circles and squares are given feet, hands, and faces, and shown to interact as if they were capable of actions such as shooting each other, and are presented to patients along with sentences like “The square shoots the circle.” It is hard to know what the aphasic patients might have made of these stimuli. Did they take the pictures to depict actions, assigning imaginary agency properties to inanimate objects, thus possibly invoking the action-agency situation? Or did they focus on the inherent inanimacy of the objects, invoking the inanimacy-position (or perhaps an inanimacy-recipient) situation ? Or were they confused? What they did, as a group, was to choose the correct picture in 84 of 120 trials in the active voice, and in 68 of 120 trials in the passive. On this account, several principles might be operative. For the active, we assume recognition of the active voice, and could suppose that agency is assigned by virtue
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of the active nature of the picture. Then principles 8 and 9 apply, as to usual actives with words depicting realistic situations. The passive, however, seems to require an account in which the patients simply fail to appreciate the relation between voice, position, and thematic role, suggesting a tendancy to interpret any noun as agent. Or, in the more complicated passive voice, the patients may be less able to apply either a “sentence” or a “locative” strategy, and apply principle 11 and a variant of principle 13, such as 14: 14. In these special circumstances, the word after the verb is recipient. These conflicting principles would also produce random results. These possibilities aside, there is a simpler solution. The main source of discrepant data in the passive constructions is one patient, B.L., who overwhelmingly assigns agency to the first noun. The authors remark that “B.L. proves a model of inconsistency” (Schwartz et al., 1980, p. 261) and give details of his performance which indeed suggest he has the most trouble adopting any consistant stratagy. So, let us remove his scores from this especially confusing task. Then we have 72 of 96 responses correct in the active voice, and 65 of 96 responses correct in the passive. Principles 7, 8, and 9 give the expected results for the actives, and principles 7, 10, and 11 give the expected results for the passive-on the assumption that the patients are operating in the “sentence” frame of mind. We have now accounted for the entirety of the data presented by these authors, in both production and comprehension tasks, and for both sentences and locative prepositional phrases. Saffran et al. (1980) only account for some of the data in a principled way. We have accounted for the pattern of results on the assumptions that the patients both map thematic roles onto lexical items and map thematically marked nouns onto positions around verbs and prepositions. We have not had to make use of undefined notions such as “potency” or “salience,” as was necessary for Schwartz et al. We therefore are authorized to accept this analysis of the data, since it is both more general and more principled. Let us now turn to some implications of this analysis. II First, we must reject the claim Saffran et al. make that thematic relations are among the linguistic structures not appreciated and not used by agrammatic patients. If the analysis just presented is correct, agrammatic patients do appreciate that language encodes these aspects of semantic representations, can map these semantic functions onto individual words, and can relate this aspect of the semantic information associated with a word to the position of a word in a sentence or a phrase. It does not appear that the agrammatic has lost any aspect of this system. What seems, rather, to be the case, is that the agrammatic has added a set of principles dealing with intrinsic animacy of nouns to the set dealing with
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the thematic role of nouns in establishing the mapping between “wordorder” and thematic relations conveyed by a sentence or phrase. Several points can be made about this addition to the usual English mapping. First, the existence of a mapping between “word order” and a hierarchy of nouns (or words) based on animacy (and on further distinctions within the category of animacy) is a feature of the grammars of some languages, though not of English. Navaho, for instance, requires that animate nouns precede inanimate nouns, and that within the animate group, terms referring to adult humans precede terms referring to children who talk, which in turn precede terms referring to nonverbal children, which in turn precede terms referring to animals. Though the English agrammatic seems to be adding a principle foreign to English, it is a principle which is consistant with universal grammar. Second, we may note that notions like agency, instrument, etc., include the notion of animacy. Agents are, roughly, animate beings who initiate events or accomplish actions; instruments are, roughly, inaminate objects that accomplish actions, etc. Though the data presented by Saffran et al. (1980) argue that agrammatic patients appreciate both notions like agency and notions like animacy, we might speculate that some patients might show interesting dissociations in this regard. Perhaps there are patients who appreciate both animacy and the notion of initiating of an action, but not the combination of the two; such patients would presumably not distinguish agentive and instrumental subjects of sentences. More subtle effects might also be found. There is a clear difference in the sense of instrumentality in 15 and 16. 15. John broke the window with a stone. 16. A stone broke the window. In 16, but not 15, “a stone” is perceived as the proximate cause of the window’s breaking. The difference in sense is paralleled in 17 and 18. 17. The window was broken with a stone. 18. The window was broken by a stone. Perhaps these more subtle distinctions could be lost to an aphasic patient who retained the less subtle distinction between agents and instruments. Third, we may speculate as to why different principles need to be formulated for the sentence cases and the locative constructions. Some quite simple possibilities come to mind. The pictures which are related to a locative convey static scenes. Perhaps the basis for the perceptual and conceptual organization of such pictures is the item in which another resides. If so, the locative noun may be highlighted. The usual prepositional arrangement in English puts it last, and agrammatics may use this arrangement. Since the noun highlighted is usually inanimate, the effects of an animacy stratagy may be such as to put inanimate nouns last. In sentences depicting the active situations used to elicit sentences in these experiments, the initiator of the action may be the most important item for the perceptual/conceptual analysis of the picture. Thus agents and
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instruments are highlighted: in the active voice, these come first. Given that many initiators of action are animate, the animacy effect focuses on animate objects, and also places them first. Let us now turn to the second interpretive claim of Saffran et al., that abstract notions like subject and predicate are not used by the agrammatic patient. We have accounted for the data on the assumption that agrammatic patients map thematically marked words onto positions around other words. Clearly, the data presented support a more abstract analysis of the linguistic structures involved in this mapping. At the least, we seem secure in the interpretation that these patients appreciated lexical categories, and we can rephrase the statement to say that they mapped thematically marked nouns onto positions around verbs and prepositions. Is there any evidence that yet more abstract analyses apply to the results; such as, that the patients map thematically marked noun phrases onto subject and object configurations? Let me briefly indicate the distinction I am making here. Saffran et al. write of the “word-order” problem in agrammatism, and of a mapping between thematic relations and word order, as if such a mapping existed in standard English. The terminology they use is inaccurate, however. Thematic relations are mapped onto constituents of certain sorts, like noun phrases, not onto wora’s, directly. Furthermore, the linear order of constituents alone does not determine the mapping. Aspects of sentence form such as voice marking on the verb enter into the linear mapping, as recognized by the authors. But even within a single voice, constituent order must be supplemented by facts about constituent hierarchy to define abstract configurations like “subject” or “object” for this mapping to be achieved. In 19, “zebra” immediately precedes “ate”, but “elephant” is its subjects and plays the role of agent in its functional argument structure, because the notion of subject is defined over the tree structure 20: 19. The elephant that nudged the zebra ate the grass 20.
/“\, /Np\
VP
/\
AAiiz The elephant
that nudged the zebra
ate
the grass
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NOTES AND DISCUSSION
In Part I, I phrased principles 1-14 in terms of analytic notions like “precedes” and “follows.” These notions, applied to lexical categories, cio seem to enter into the mapping of thematically marked nouns onto sentence form. But there is no evidence in the present experiment which bears on these patients’ utilization or knowledge of the more abstract and complex configurations which constitute notions like subject or object. Other work (Zurif & Caramazza, 1976) does suggest that agrammatics fail to construct grammatical relations, but this work can be accepted only tentatively. (See Caplan, 1983, for discussion.) The distinction between notions like precedence and configurationally defined grammatical relations is related to a fundamental idea expressed by Chomsky (1982), that of a “primitive basis of concepts” from which others are derivable. Such a primitive basis, for universal grammar, must meet a number of conditions, one of which is “epistemological priority”: The primitive basis must meet a condition of epistemological priority. That is, still assuming the idealization to instantaneous language acquisition, we want the primitives to be concepts that can plausibly be assumed to provide a preliminary, prelinguistic analysis of a reasonable selection of presented data, that is, to provide the primary linguistic data that are mapped by the language faculty onto a grammar; relaxing the idealization to permit transitional stages, similar considerations still hold. It would, for example, be reasonable to suppose that such concepts as “precedes” or “is voiced” enter into the primitive basis, and perhaps such notions as “agent-of-action” if one believes, say, that the human conceptual system permits analysis of events in these terms independently of acquired language. But it would be unreasonable to incorporate, for example, such notions as “subject of a sentence” or other grammatical relations within the class of primitive notions, since it is unreasonable to suppose that these notions can be directly applied to linguistically unanalyzed data. (Chomsky, 1982, p. IO)
It is an intriguing thought that agrammatic patients, or some other group of language-impaired subjects, may retain this primitive basis and not the structures complexly defined over it. Thus it may be that Saffran and colleagues are correct in their interpretation that agrammatics do not retain notions like subject and object, and this may entail a reliance on their part on epistemologically more available analyses. In this case, some rather interesting questions arise for languages that rely on devices which obviate the critical role of constituent structure in mapping thematic relations. Italian, for instance, permits relatively free, constituent order and thematic role is signaled by verbal-noun agreement. Languages like German, Russian, and SerboCroatian, among others, mark thematic roles through case-marking systems, some involving markings on prenominal elements, others involving markings on nouns directly. Which of these devices might be available are questions which would be of interest. Whether any genera1 statements might be forthcoming regarding the availability of these various devices,
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either in terms of some structural linguistic theory of agrammatism (Kean, 1977) or in terms of notions such as epistemologically primitive analyses and other conditions met by a primitive basis of concepts in linguistics, is an interesting question. Finally, in this regard, we may note that the relationship between syntactic and morphological devices and identification of thematic roles is variable over languages. Ergative languages case mark the subject of intransitive and the object of transitive verbs identically. Just as the feature of animacy, operative in Navaho, seemsto intrude into the mapping of thematic role onto constituent order in English, the basic analysis underlying an ergative rather than an accusative/nominative system may intrude into the mapping from thematic role to a conjunction of case marking and sequential features of constituents in a language which uses one of these systems. Finally, what does the analysis presented in Part I have to say about the agrammatic syndrome? It is again helpful to begin with Saffran and colleagues’ assessment, because, though incorrect on the present reanalysis, it provides a useful framework for answering this question. Saffran et al. argue for a view of agrammatism which sees the deficit as residing at a “deep” level of linguistic representations, the appreciation of the linguistic syntactic notion of grammatical relations and the linguistic semantic notion of thematic relations. They draw two conclusions from this characterization which are worth considering here. First, they argue that it can be related to a model of sentence production developed from analysis of normal speech errors by Garrett (1976). Second, they argue that it constitutes a point against the “phonological hypothesis” of agrammatism developed by M. -L. Kean (1977). The second point is the easier to deal with. Saffran et al. seriously misrepresent Kean’s hypothesis. Their construal of the phonological hypothesis is that it claims that phonological features of language will be affected in agrammatism. The hypothesis makes no such claim, however. It states that agrammatism is to be defined over a set of linguistic items characterized by their phonological properties. The role of that set of items in language structure and in language processing is not necessarily uniquely related to the sound system, nor need other aspects of the phonology be affected. Taken in its intended form, the phonological hypothesis is entirely compatible with a disturbance in syntactic structure (Kean, 1982). Whether it is compatible with a problem in the mapping of thematic role onto constituent order is not entirely clear, given the indeterminacy of present models of language processing. But this latter is a moot point, given the arguments in Part I of this paper. Given the re-analysis of the Saffran et al. data presented here, it seems clear that, if this analysis is to be related to Garrett’s model of sentence
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production, the level at which the disturbance lies is the “positional” rather than the “functional” level. Even this may not be the case. The analysis is neutral as to whether agrammatics do or do not construct syntactic forms corresponding to notions such as subject and object. If they do, there would seem no basis for ascribing any disturbance in structure-generation to them. Rather, normative semantic properties (thematic roles) and normative syntactic structures are utilized and complicated by additional, usually inoperative, principles. Further work, along the lines mentioned above, would bear on these possibilities. In sum, there is no “word-order problem” in agrammatism. The term “word order” is, in any case, a misnomer. A re-analysis of data provided by Saffran et al. accounts for their results quite generally only by asserting the statements these authors seek to deny: that agrammatic patients appreciate the linguistic semantic notions of thematic relations and map them onto constituent order. If there is a structural defect in agrammatism, it would seem to be in the use or knowledge of higher-order syntactic structures, such as those required to define grammatical relations. I have proposed one such deficit (Caplan, 1981, 1982), quite consistent with, though not proven by, the analysis presented here. Kean’s proposals (Kean, 1982) are also consistent with the present analysis. Both my work and Kean’s constitute variants of the “function word theory” of agrammatism. Though Saffran et al. do not directly comment on this group of theories, their rejection of Kean’s hypothesis might make a reader suspect they believe their experiments argue against these theories. It therefore seemsappropriate to end this note with the observation that these theories, in their present formulation, directly lead to accounts of an inability to construct syntactic structures of the sort which might be affected in agrammatism and that, to the extent that the analysis presented here bears on these theories, it supports them. REFERENCES Caplan, D. 1981. Syntactic competence in agrammatism, a lexical hypothesis. Delivered at Neuroscience Research Program, Boston, MA. Caplan, D. 1983. Syntactic and semantic structures in agrammatism. In M. -L. Kean (Ed.), Agrammatism. N.Y.: Academic Press. In press. Chomsky, N. 1982. Lectures on government and binding. Dordrecht: Foris. Garrett, M. F. 1976. Syntactic processes in sentence production. In R. Wales & E. Walker (Eds.), New approaches to language mechanisms. Amsterdam: North-Holland. Kean, M. -L. 1982. Three perspectives for the analysis of aphasic syndromes. In M. A. Arbib, D. Caplan, & J. C. Marshall (Eds.), Neural models of language processes. New York: Academic Press. Kean, M. -L. 1977. The linguistic interpretation of aphasic syndromes. Cognition, 5, 946. Saffran, E., Schwartz, M., & Marin, 0. 1980. The word order problem in agrammatism II: Production. Brain and Language 10, 263-280.
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Schwartz, M., Saffran, E., & Marin, 0. 1980. The word order problem in agrammatism I: Comprehension. Brain and Language 10, 149-262. Zurif, E., & Caramazza, A. 1976. Psycholinguistic structures in aphasia: Studies in syntax and semantic. In H. Whitaker & H. Whitaker (Eds.), Studies in neurolinguistics I. New York: Academic Press.
AND
LANGUAGE
20, 155-165 (1983)
NOTES AND DISCUSSION A Note on the “Word-Order Problem” in Agrammatism DAVID Montreal
CAPLAN
Neurological
Institute
This brief note has two parts. First, it presents an analysis of the ability of English agrammatic patients to assign the thematic roles of agent, instrument, theme, and locative to noun phrases in active and passive sentences and prepositional phrases. Data regarding this ability have been presented by Schwartz, Saffran, and Marin (Brain and Language, 10, 149-262 (1980)) regarding comprehension, and by Saffran, Schwartz, and Marin (Brain and Language, 10,263280 (1980)) regarding production. These authors claim their data show that English agrammatic aphasics do not map “word order” onto thematic information. However, a very simple set of principles accounts for all their results, including results which are discrepant in their treatment, but requires that English agrammatics assign thematic roles to NPs in part by virtue of the position of an NP in a sentence or a phrase. In the second part of this note, several issues raised by this re-analysis are briefly discussed.
I Saffran et al., (1980) presented data regarding the order of nouns around verbs in sentences describing simple pictures of actions, produced by five agrammatic patients. The authors note a strong effect of animacy upon the position of the nouns around the verbs. When an animate noun acts upon an inanimate noun (as in a picture of a boy hitting a ball), the resulting sentence almost always has the animate noun first-that is, before the verb-while when an animate noun acts upon another animate noun (as in a picture of a boy pushing a girl), the animate noun agent precedes the verb in about a third of storable sentences. The authors suggest that thematic roles are not mapped onto word-order positions, and that animacy determines the position of nouns around verbs. A I have benefited in the preparation of this note from discussions with Mary-Louise Kean, John Goldsmith, and Remu Job. Any remaining errors in this analysis or in its interpretation are solely my responsibility. Send requests for reprints to Dr. David Caplan, Department of Neurology, Montreal Neurological Institute, 3801 University, Montreal, Quebec, Canada H3A 2B4. 155
0093-934X/83 $3.00 Copyright 0 1983 by Academic Press. Inc. All rights of reproduction in any form reserved.
156
NOTES AND DISCUSSION
similar set of results occurred when the experiment was replicated using a sentence anagram rather than a verbal production task. There were, however, some data which did not entirely correspond to the notion that animacy alone determined word order. When two inanimate nouns appeared in a picture (as in a picture of a boat pulling a truck), the noun depicted as instrument (in this case “the boat”) was produced before the verb virtually all the time. Furthermore, when an inanimate noun was acting upon an animate noun (as in a picture of a ball hitting a boy), the inanimate noun preceded the animate noun about half the time, with the animate noun preceding the inanimate noun the other half of the time. If animacy alone determines word order of nouns around verbs, one should find that the inanimate/inanimate pairs were treated like the animate/animate pairs (either noun appearing first), while the inanimate/animate pairs should have shown consistent reversals. The authors mention these problems, and conclude that a more general factor, termed “salience” or “potency” accounts for these orderings. One feature of the semantics of the words in question which does not enter into potency or salience, however, is knowledge of the thematic role played by the word involved, according to the authors. They specifically claim that such knowledge is not available to agrammatic patients, who, they say, lack the linguistic concept of thematic relations. There is a quite simple set of rules which does account for the pattern of data, however, and which requires that we assume that the patients know that language encodes thematic relations, and that lexical items can be assigned thematic roles. The rules are the following: 1. Assume the patient is producing sentences in the active voice. 2. Assume that the patient tends to put animate nouns before the verb. 3. Assume the patient tends to put nouns bearing the thematic role of agent or instrument before the verb. Principles 2 and 3 assume that the patient knows which words are animate and that he can assign thematic roles to items in a picture and then assign those roles to words. Principles 1 and 2 are accepted by Saffran and colleagues (1980). The first prerequisite underlying 3-the semantic parsing of pictures into thematic terms by these patients-is also accepted by these authors. What is at issue is the second prerequisite for assumption 3-that thematic information derived from the analysis of a picture can be mapped onto words. Assuming these principles are additive in their effects, they account for the production data in a straightforward way. In the animate-agent/ inanimate-theme cases, 2 and 3 both dictate the animate agent will go first. It does. In the animate-agent/animate-theme cases, 2 and 3 will dictate that the animate agent goes first, but 2 will also dictate that the animate theme go first (because of its animacy). The animate agent goes first two-thirds of the time; the animate theme goes first one-third of the time. The two-to-one ratio of which noun goes first exactly reflects the
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additive effects of each of these principles upon word order. In the inanimate-instrument/animate-theme cases, principle 2 dictates that the animate theme go first, and principle 3 dictates that the inanimate-instrument go first; the results are a 50-50 split, which is the case in the data. Finally, in the inanimate-instrument/inanimate-theme cases, only principle 3 applies, putting the inanimate instrument first-such is indeed the case. For the production of locative phrases, the data are that when the two nouns represented in a picture are both inanimate, the inanimate locative noun goes after the preposition about two-thirds of the time, and when the picture represents an animate noun in relation to an inanimate locative noun, the animate noun always precedes the preposition. That is, for pictures showing a pencil in a sink, agrammatics put “the pencil” first about two-thirds of the time and “the sink” first about one-third; for pictures of a bird in a cage, they put “the bird” first almost all the time. The principles which seem to be in operation are: 4. Assume the patient is producing forms of the sort: N Prep N; 5. Assume the patient puts inanimate nouns after the preposition; 6. Assume the patient puts locative nouns after the preposition. Then the data again follow naturally. In the inanimate-themeiinanimatelocative cases, principles 5 and 6 will both affect the inanimate-locative noun, and principle 5 will affect the inanimate theme. As in the sentence cases with animate-agent/animate-theme nouns, we would expect a twothirds/one-third split of responses, which is what occurs. In the animatetheme/inanimate-locative cases, only principle 6 applies, and we get the correct order of words, as observed. The data regarding comprehension provided by these same authors (Schwartz et al., 1980) are also accounted for by principles of exactly the same type. First consider what their patients did in the way of understanding semantically reversible simple active and passive declarative transitive sentences in which all nouns are animate. The authors do not give actual scores, but these are recoverable (or very nearly--I may have misread the exact scores in their Fig. 1 by one or two errors, which would not substantially change the analysis). As a group, the patients produced the correct word order in 75 of 100 active sentences, and in 68 of 100 passive sentences. Suppose the operative principles are: 7. The patient recognizes the voice of the sentence. 8. In the active, assign the noun before the verb as the agent. 9. In the active, assign an animate noun as agent. This strategy will produce a situation where two factors combine to assign agency to animate nouns preceding verbs, and one factor assigns agency to an animate noun following the verb. The results (a three-fourths/onefourth split) are very close to this pattern. Now, consider the following principles for the passive. Principle 7 still applies, and we add:
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10. In the passive, assign an animate noun as agent (same as principle 9). 11. In the passive, assign the noun following the verb as the agent. Again, a two-thirds/one-third split of responses is predicted, as is observed. Notice that, except for assigning agency to a post verbal noun in the passive, these principles are exactly the same as those needed for the production data. All that we are adding here is the assumption that the patient recognizes, but not use, the passive form (which is a very reasonable assumption), and that when he recognizes the passive form, he assigns agency to the postverbal rather than the preverbal noun (which is essentially the most expected consequence of “recognizing” the passive form). The authors also report comprehension data for locative constructions. In these cases, only inanimate objects (drawings of circles and squares) were used. Again, I had to estimate the actual error scores from their Fig. 3, but my estimates are certainly accurate enough to support the analysis. Subtracting out lexical errors according to the authors’ Model 2, (which they use themselves), there were 103 correct responses and 91 reversals out of 240 sentences. We account for this pattern by: 12. In a locative construction, an inanimate noun is locative. Here, then, is the only place so far where animacy alone determines thematic role. However, if we make a different assumption about lexical errors-the authors’ Model 3-we get a somewhat different pattern. In this case, there are 114 correct and 91 reversed selections of pictures in these locative phrases-a split close to two-thirds/one-third. If this is the right way to handle lexical errors, we would account for the data by principle 12, above, and principle 13: 13. In a locative construction, the noun after the preposition is locative. In combination, these two principles assign two factors to put the “right” noun after the preposition, and only one to put the “wrong” noun after the proposition-as the data roughly suggest. Principles 12 and 13 are quite similar to 5 and 6. Finally, Schwartz et al. (1980) look at a situation in which line drawings of circles and squares are given feet, hands, and faces, and shown to interact as if they were capable of actions such as shooting each other, and are presented to patients along with sentences like “The square shoots the circle.” It is hard to know what the aphasic patients might have made of these stimuli. Did they take the pictures to depict actions, assigning imaginary agency properties to inanimate objects, thus possibly invoking the action-agency situation? Or did they focus on the inherent inanimacy of the objects, invoking the inanimacy-position (or perhaps an inanimacy-recipient) situation ? Or were they confused? What they did, as a group, was to choose the correct picture in 84 of 120 trials in the active voice, and in 68 of 120 trials in the passive. On this account, several principles might be operative. For the active, we assume recognition of the active voice, and could suppose that agency is assigned by virtue
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of the active nature of the picture. Then principles 8 and 9 apply, as to usual actives with words depicting realistic situations. The passive, however, seems to require an account in which the patients simply fail to appreciate the relation between voice, position, and thematic role, suggesting a tendancy to interpret any noun as agent. Or, in the more complicated passive voice, the patients may be less able to apply either a “sentence” or a “locative” strategy, and apply principle 11 and a variant of principle 13, such as 14: 14. In these special circumstances, the word after the verb is recipient. These conflicting principles would also produce random results. These possibilities aside, there is a simpler solution. The main source of discrepant data in the passive constructions is one patient, B.L., who overwhelmingly assigns agency to the first noun. The authors remark that “B.L. proves a model of inconsistency” (Schwartz et al., 1980, p. 261) and give details of his performance which indeed suggest he has the most trouble adopting any consistant stratagy. So, let us remove his scores from this especially confusing task. Then we have 72 of 96 responses correct in the active voice, and 65 of 96 responses correct in the passive. Principles 7, 8, and 9 give the expected results for the actives, and principles 7, 10, and 11 give the expected results for the passive-on the assumption that the patients are operating in the “sentence” frame of mind. We have now accounted for the entirety of the data presented by these authors, in both production and comprehension tasks, and for both sentences and locative prepositional phrases. Saffran et al. (1980) only account for some of the data in a principled way. We have accounted for the pattern of results on the assumptions that the patients both map thematic roles onto lexical items and map thematically marked nouns onto positions around verbs and prepositions. We have not had to make use of undefined notions such as “potency” or “salience,” as was necessary for Schwartz et al. We therefore are authorized to accept this analysis of the data, since it is both more general and more principled. Let us now turn to some implications of this analysis. II First, we must reject the claim Saffran et al. make that thematic relations are among the linguistic structures not appreciated and not used by agrammatic patients. If the analysis just presented is correct, agrammatic patients do appreciate that language encodes these aspects of semantic representations, can map these semantic functions onto individual words, and can relate this aspect of the semantic information associated with a word to the position of a word in a sentence or a phrase. It does not appear that the agrammatic has lost any aspect of this system. What seems, rather, to be the case, is that the agrammatic has added a set of principles dealing with intrinsic animacy of nouns to the set dealing with
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the thematic role of nouns in establishing the mapping between “wordorder” and thematic relations conveyed by a sentence or phrase. Several points can be made about this addition to the usual English mapping. First, the existence of a mapping between “word order” and a hierarchy of nouns (or words) based on animacy (and on further distinctions within the category of animacy) is a feature of the grammars of some languages, though not of English. Navaho, for instance, requires that animate nouns precede inanimate nouns, and that within the animate group, terms referring to adult humans precede terms referring to children who talk, which in turn precede terms referring to nonverbal children, which in turn precede terms referring to animals. Though the English agrammatic seems to be adding a principle foreign to English, it is a principle which is consistant with universal grammar. Second, we may note that notions like agency, instrument, etc., include the notion of animacy. Agents are, roughly, animate beings who initiate events or accomplish actions; instruments are, roughly, inaminate objects that accomplish actions, etc. Though the data presented by Saffran et al. (1980) argue that agrammatic patients appreciate both notions like agency and notions like animacy, we might speculate that some patients might show interesting dissociations in this regard. Perhaps there are patients who appreciate both animacy and the notion of initiating of an action, but not the combination of the two; such patients would presumably not distinguish agentive and instrumental subjects of sentences. More subtle effects might also be found. There is a clear difference in the sense of instrumentality in 15 and 16. 15. John broke the window with a stone. 16. A stone broke the window. In 16, but not 15, “a stone” is perceived as the proximate cause of the window’s breaking. The difference in sense is paralleled in 17 and 18. 17. The window was broken with a stone. 18. The window was broken by a stone. Perhaps these more subtle distinctions could be lost to an aphasic patient who retained the less subtle distinction between agents and instruments. Third, we may speculate as to why different principles need to be formulated for the sentence cases and the locative constructions. Some quite simple possibilities come to mind. The pictures which are related to a locative convey static scenes. Perhaps the basis for the perceptual and conceptual organization of such pictures is the item in which another resides. If so, the locative noun may be highlighted. The usual prepositional arrangement in English puts it last, and agrammatics may use this arrangement. Since the noun highlighted is usually inanimate, the effects of an animacy stratagy may be such as to put inanimate nouns last. In sentences depicting the active situations used to elicit sentences in these experiments, the initiator of the action may be the most important item for the perceptual/conceptual analysis of the picture. Thus agents and
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instruments are highlighted: in the active voice, these come first. Given that many initiators of action are animate, the animacy effect focuses on animate objects, and also places them first. Let us now turn to the second interpretive claim of Saffran et al., that abstract notions like subject and predicate are not used by the agrammatic patient. We have accounted for the data on the assumption that agrammatic patients map thematically marked words onto positions around other words. Clearly, the data presented support a more abstract analysis of the linguistic structures involved in this mapping. At the least, we seem secure in the interpretation that these patients appreciated lexical categories, and we can rephrase the statement to say that they mapped thematically marked nouns onto positions around verbs and prepositions. Is there any evidence that yet more abstract analyses apply to the results; such as, that the patients map thematically marked noun phrases onto subject and object configurations? Let me briefly indicate the distinction I am making here. Saffran et al. write of the “word-order” problem in agrammatism, and of a mapping between thematic relations and word order, as if such a mapping existed in standard English. The terminology they use is inaccurate, however. Thematic relations are mapped onto constituents of certain sorts, like noun phrases, not onto wora’s, directly. Furthermore, the linear order of constituents alone does not determine the mapping. Aspects of sentence form such as voice marking on the verb enter into the linear mapping, as recognized by the authors. But even within a single voice, constituent order must be supplemented by facts about constituent hierarchy to define abstract configurations like “subject” or “object” for this mapping to be achieved. In 19, “zebra” immediately precedes “ate”, but “elephant” is its subjects and plays the role of agent in its functional argument structure, because the notion of subject is defined over the tree structure 20: 19. The elephant that nudged the zebra ate the grass 20.
/“\, /Np\
VP
/\
AAiiz The elephant
that nudged the zebra
ate
the grass
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In Part I, I phrased principles 1-14 in terms of analytic notions like “precedes” and “follows.” These notions, applied to lexical categories, cio seem to enter into the mapping of thematically marked nouns onto sentence form. But there is no evidence in the present experiment which bears on these patients’ utilization or knowledge of the more abstract and complex configurations which constitute notions like subject or object. Other work (Zurif & Caramazza, 1976) does suggest that agrammatics fail to construct grammatical relations, but this work can be accepted only tentatively. (See Caplan, 1983, for discussion.) The distinction between notions like precedence and configurationally defined grammatical relations is related to a fundamental idea expressed by Chomsky (1982), that of a “primitive basis of concepts” from which others are derivable. Such a primitive basis, for universal grammar, must meet a number of conditions, one of which is “epistemological priority”: The primitive basis must meet a condition of epistemological priority. That is, still assuming the idealization to instantaneous language acquisition, we want the primitives to be concepts that can plausibly be assumed to provide a preliminary, prelinguistic analysis of a reasonable selection of presented data, that is, to provide the primary linguistic data that are mapped by the language faculty onto a grammar; relaxing the idealization to permit transitional stages, similar considerations still hold. It would, for example, be reasonable to suppose that such concepts as “precedes” or “is voiced” enter into the primitive basis, and perhaps such notions as “agent-of-action” if one believes, say, that the human conceptual system permits analysis of events in these terms independently of acquired language. But it would be unreasonable to incorporate, for example, such notions as “subject of a sentence” or other grammatical relations within the class of primitive notions, since it is unreasonable to suppose that these notions can be directly applied to linguistically unanalyzed data. (Chomsky, 1982, p. IO)
It is an intriguing thought that agrammatic patients, or some other group of language-impaired subjects, may retain this primitive basis and not the structures complexly defined over it. Thus it may be that Saffran and colleagues are correct in their interpretation that agrammatics do not retain notions like subject and object, and this may entail a reliance on their part on epistemologically more available analyses. In this case, some rather interesting questions arise for languages that rely on devices which obviate the critical role of constituent structure in mapping thematic relations. Italian, for instance, permits relatively free, constituent order and thematic role is signaled by verbal-noun agreement. Languages like German, Russian, and SerboCroatian, among others, mark thematic roles through case-marking systems, some involving markings on prenominal elements, others involving markings on nouns directly. Which of these devices might be available are questions which would be of interest. Whether any genera1 statements might be forthcoming regarding the availability of these various devices,
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either in terms of some structural linguistic theory of agrammatism (Kean, 1977) or in terms of notions such as epistemologically primitive analyses and other conditions met by a primitive basis of concepts in linguistics, is an interesting question. Finally, in this regard, we may note that the relationship between syntactic and morphological devices and identification of thematic roles is variable over languages. Ergative languages case mark the subject of intransitive and the object of transitive verbs identically. Just as the feature of animacy, operative in Navaho, seemsto intrude into the mapping of thematic role onto constituent order in English, the basic analysis underlying an ergative rather than an accusative/nominative system may intrude into the mapping from thematic role to a conjunction of case marking and sequential features of constituents in a language which uses one of these systems. Finally, what does the analysis presented in Part I have to say about the agrammatic syndrome? It is again helpful to begin with Saffran and colleagues’ assessment, because, though incorrect on the present reanalysis, it provides a useful framework for answering this question. Saffran et al. argue for a view of agrammatism which sees the deficit as residing at a “deep” level of linguistic representations, the appreciation of the linguistic syntactic notion of grammatical relations and the linguistic semantic notion of thematic relations. They draw two conclusions from this characterization which are worth considering here. First, they argue that it can be related to a model of sentence production developed from analysis of normal speech errors by Garrett (1976). Second, they argue that it constitutes a point against the “phonological hypothesis” of agrammatism developed by M. -L. Kean (1977). The second point is the easier to deal with. Saffran et al. seriously misrepresent Kean’s hypothesis. Their construal of the phonological hypothesis is that it claims that phonological features of language will be affected in agrammatism. The hypothesis makes no such claim, however. It states that agrammatism is to be defined over a set of linguistic items characterized by their phonological properties. The role of that set of items in language structure and in language processing is not necessarily uniquely related to the sound system, nor need other aspects of the phonology be affected. Taken in its intended form, the phonological hypothesis is entirely compatible with a disturbance in syntactic structure (Kean, 1982). Whether it is compatible with a problem in the mapping of thematic role onto constituent order is not entirely clear, given the indeterminacy of present models of language processing. But this latter is a moot point, given the arguments in Part I of this paper. Given the re-analysis of the Saffran et al. data presented here, it seems clear that, if this analysis is to be related to Garrett’s model of sentence
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production, the level at which the disturbance lies is the “positional” rather than the “functional” level. Even this may not be the case. The analysis is neutral as to whether agrammatics do or do not construct syntactic forms corresponding to notions such as subject and object. If they do, there would seem no basis for ascribing any disturbance in structure-generation to them. Rather, normative semantic properties (thematic roles) and normative syntactic structures are utilized and complicated by additional, usually inoperative, principles. Further work, along the lines mentioned above, would bear on these possibilities. In sum, there is no “word-order problem” in agrammatism. The term “word order” is, in any case, a misnomer. A re-analysis of data provided by Saffran et al. accounts for their results quite generally only by asserting the statements these authors seek to deny: that agrammatic patients appreciate the linguistic semantic notions of thematic relations and map them onto constituent order. If there is a structural defect in agrammatism, it would seem to be in the use or knowledge of higher-order syntactic structures, such as those required to define grammatical relations. I have proposed one such deficit (Caplan, 1981, 1982), quite consistent with, though not proven by, the analysis presented here. Kean’s proposals (Kean, 1982) are also consistent with the present analysis. Both my work and Kean’s constitute variants of the “function word theory” of agrammatism. Though Saffran et al. do not directly comment on this group of theories, their rejection of Kean’s hypothesis might make a reader suspect they believe their experiments argue against these theories. It therefore seemsappropriate to end this note with the observation that these theories, in their present formulation, directly lead to accounts of an inability to construct syntactic structures of the sort which might be affected in agrammatism and that, to the extent that the analysis presented here bears on these theories, it supports them. REFERENCES Caplan, D. 1981. Syntactic competence in agrammatism, a lexical hypothesis. Delivered at Neuroscience Research Program, Boston, MA. Caplan, D. 1983. Syntactic and semantic structures in agrammatism. In M. -L. Kean (Ed.), Agrammatism. N.Y.: Academic Press. In press. Chomsky, N. 1982. Lectures on government and binding. Dordrecht: Foris. Garrett, M. F. 1976. Syntactic processes in sentence production. In R. Wales & E. Walker (Eds.), New approaches to language mechanisms. Amsterdam: North-Holland. Kean, M. -L. 1982. Three perspectives for the analysis of aphasic syndromes. In M. A. Arbib, D. Caplan, & J. C. Marshall (Eds.), Neural models of language processes. New York: Academic Press. Kean, M. -L. 1977. The linguistic interpretation of aphasic syndromes. Cognition, 5, 946. Saffran, E., Schwartz, M., & Marin, 0. 1980. The word order problem in agrammatism II: Production. Brain and Language 10, 263-280.
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Schwartz, M., Saffran, E., & Marin, 0. 1980. The word order problem in agrammatism I: Comprehension. Brain and Language 10, 149-262. Zurif, E., & Caramazza, A. 1976. Psycholinguistic structures in aphasia: Studies in syntax and semantic. In H. Whitaker & H. Whitaker (Eds.), Studies in neurolinguistics I. New York: Academic Press.