Published on June 15, 2007
Slide1: Investigations of Grammar in Autism: Knowledge of Passives and Binding Alexandra Perovic1, Nadya Modyanova1, Ellen Hanson2, Leonard Rappaport2, Ken Wexler1 1Massachusetts Institute of Technology, 2Children’s Hospital Boston Experiment I: Passives two choice picture task actional verbs: kiss, push, hold non-actional verbs: love, see, a. Active c. Active remember Marge pushes Homer. Lisa loves Bart. b. Passive d. Passive Homer is pushed. Bart is loved. Homer is pushed by Marge. Bart is loved by Lisa. (6 items in each condition) Summary and Interpretation of Results Passives: Children with autism perform poorer than verbal and non-verbal MA-matched controls on all types of passives: short and long, of actional and non-actional verbs. TD controls show difficulties with passives of non-actional verbs only, in line with reports in the literature. Children with autism lack A-chains. Due to underdeveloped grammar, they cannot even resort to a linguistic strategy of interpreting non-actional passives as adjectival passives. Binding: Children with autism show some difficulties interpreting personal pronouns, just like the TD controls, but show severe difficulties interpreting reflexives, unlike either verbal or non-verbal MA matched controls. Children with autism cannot interpret the syntactic relation between the reflexive and its antecedent. Their interpretation of coreference however is in line with MA-matched TD controls. The fact that participants with autism performed worse than even their verbal MA-matched controls suggests that grammar is specifically impaired in this disorder. References Borer, H., andamp; Wexler, K. (1987). The maturation of syntax. In Roeper andamp; Williams (eds), Parameter Setting, 23-172. Dordrecht: Reidel. Chien, Y-C. andamp; Wexler, K. (1990). Children’s knowledge of locality conditions in binding as evidence for the modularity of syntax and pragmatics. Language Acquisition 1 (3): 225-295. Churchill D.W. (1972). The relationship of early infantile autism and developmental language disorders of childhood. Journal of Autism and Child Schizophrenia 2: 182-197. Hirsch, C. andamp; Wexler, K. (2004). Children’s passives and their resulting interpretation. Paper presented at GALANA 2004. Kjelgaard M. andamp; Tager-Flusberg, H. (2001). An investigation of language impairment in autism: Implications for genetic subgroups. Language and Cognitive Processes 16: 287-308. Roberts, J., Rice, M. andamp; Tager-Flusberg, H. (2004). Tense marking in children with autism. Applied Psycholinguistics 25: 429-448. Tager-Flusberg, H. (1981). Sentence comprehension in autistic children. Applied Psycholinguistics 2: 5-24. Is grammar impaired in autism? Standard view: Functional aspects of language are impaired (pragmatics, conversational skills, prosody) Computational aspects of language are spared (morphosyntax, phonology). BUT: Very early research (e.g. Churchill 1972) and very recent research (e.g. Kjelgaard andamp; Tager-Flusberg, 2001; Roberts, Rice andamp; Tager-Flusberg, 2004) suggest this view is inaccurate: a large proportion of children with autism omit functional morphemes and especially verbal inflection in their spontaneous speech and in elicited production. What about complex syntax in autism? Tager-Flusberg (1981) suggests difficulties on actional passives The goal of this study: To investigate aspects of complex grammar in children with autism, that of passives and binding, compared to typically developing (TD) control children functioning at similar verbal or non-verbal mental age (MA). Participants 11 children clinically diagnosed with autism age = 6;6-16 (mean age = 11) non-verbal IQ: 40-103 (mean 67, SD=21.4); receptive vocabulary SS: 40-87 (mean 58, SD=16.8) Two groups of individually matched TD controls a. matched on non-verbal MA (KBIT 1); age = 4 – 7;8 (mean age = 6) b. individually matched on verbal MA (PPVT 3); age = 3;6 – 8 (mean age = 5) (only ‘average’ controls were used – SS ranging 90-109) Predictions for children with autism Passives: If grammar is not impaired in autism, children with this disorder will show either intact knowledge of both types of passives, or at least knowledge comparable to that of TD controls functioning at similar MA levels: difficulties with non-actional, but not actional passives. If their grammar is impaired, children with autism will show poor performance on all passives in comparison to TD controls functioning at similar MA levels. Binding: If only pragmatic, but not syntactic knowledge is affected in autism, children with this disorder will show difficulties interpreting personal but not reflexive pronouns. If syntax is also affected in autism, children may show difficulties interpreting reflexive pronouns, the pattern not evidenced in TD controls at any stage of language development. Acquisition of Passives in TD Actional passives (pushed, kissed) are mastered before non-actional passives (seen, loved) (Maratsos et al 1980, Gordon andamp; Chafetz, 1990; Hirsch andamp; Wexler, 2004). Explanation: According to Borer andamp; Wexler (1987), young children lack A-chains. Their seemingly good performance on actional passives is a result of a linguistic strategy of interpreting actional passives as adjectival, where no formation of A-chain is required. Acquisition of Binding in TD Reflexive pronouns are mastered before personal pronouns (‘Delay of Principle B Effect’). Explanation: There is a distinction between syntactic binding and coreference: children know the syntactic principle governing the distribution of reflexives, but may have difficulties executing non-syntactic (pragmatic) principles that govern coreference (Chien andamp; Wexler, 1990). Experiment II: Binding two choice picture task a. Name Pronoun: Bart’s dad is washing him. c. Control Possessive: Bart’s dad is petting a dog. b. Name Reflexive: Bart’s dad is washing himself. d. Control Name: Bart is petting a dog. (8 items in each condition) Conclusion Grammar IS impaired in autism. Results: Binding Main effect of sentence type: F(3,90) = 13.606, p andlt; .001 Main effect of group: F(2,30) = 8.049, p = .002 Interaction bet. sen.t type andamp; group: F(6,90)=5.818, pandlt;.001 Results: Passives Main effect of sentence type: F(5,150) = 38.061, p andlt; .001 Main effect of group: F(2,30) = 38.56, p andlt; .001 Interaction between sent. type andamp; group: F(10,150), p andlt; .001 This research is sponsored by the Anne and Paul Marcus Family Foundation and the Brain Development and Disorders Project at MIT. We thank all our participants and their families.