SLI Children's Delayed Acquisition of Passive

1. SLI Children's Delayed Acquisition of Passive Mabel L. Rice, Kenneth Wexler, & Jennifer Francois Paper Presented at the BU Conference on Language Development Boston, MA, November 1-4, 2001

2. ABSTRACT Children’s accurate comprehension of passive sentences, such as “The horse was kicked by the goat,” appears around 4 to 5 years of age in typically developing children. There has been limited empirical documentation of the acquisition of passives by children with SLI. In this study, we examined passive comprehension in 10-year-old children with SLI and found that they understood full passives as well as age controls. Grammaticality judgment tasks reveal that affected children can detect semantic errors of agent assignment, as well as omission of the participial morphology, but they are more likely than younger controls to accept omission of the

3. Abstract (continued) auxiliary was. In a follow up study, we found that 5-year-old children with SLI comprehend passives at a level commensurate with children 2 years younger, at equivalent levels of vocabulary comprehension (i.e., around 50%, a chance level of responding, which is below age controls, 83%). At the same time, the SLI children perform lower than the younger controls on grammatical tense in production probes (around 40% vs. 69%). Acquisition of passives for SLI children appears to track with receptive vocabulary, as part of a general language delay, whereas grammatical tense levels are lower than expected.

4. Normative Acquisition Typically developing children of 4 to 5 years of age know the passive structure (e.g., de Villiers and de Villiers, 1972; Harris, 1976; Strohner & Nelson, 1973) The monkey kissed the goat. The goat was kissed by the monkey.

5. Reported Deficits in Children with SLI Teenagers with grammatical SLI do not understand full verbal passive constructions (van der Lely, 1996), a deficit attributable to an underlying problem with constituent movement (?) The fish is eaten by the man

6. The Purpose of this Study To investigate children with SLI, to determine if they understand full “by” passives, and how performance on passive tasks corresponds with performance on EOI probes and general vocabulary levels.

7. Study 1: Older Children • Older Child Participants 19 10-year-old children 17 age-equivalent controls 16 8-year-old lexically- equivalent controls (PPVT raw scores)

8. Three Tasks for Older Children 1) Comprehension Stromswold’s 32-item task for reversible full passives, with toy animals. Examiner: “The goal kicked the horse.” Child: act out action with toy animals [Verbal item set: Kiss, slap, touch, hug, kick, lick, tickle, push]

9. 2) TNS Probe TNS probe: 3rd personal singular present –s, past –ed Examiner: “Here is a policeman. Tell me what he does.” Child: “He helps people.” Examiner: “Here the boy is raking. Now he is done. Tell me what he did with the leaves.” Child: “He raked all of them into a pile.”

10. 3) Grammaticality Judgment Task Examiner says: “Imagine that Felix is watching some children playing. Felix does not speak English very well. He knows that there are two boys, one named Bill and one named Harry, and two girls one named Martha and one named Patsy. [Show the child each character’s picture. Name each one, and be sure the child notices each.] I’m going to tell you some stories. In these stories, the children are playing and some of the children’s mother’s are there too. Felix wants to tell what happened, but he gets confused. He tries several ways to describe what happened. What I want you to do is listen carefully and tell me if what he says is a correct way to say what happened. More than one sentence could be correct. I’m going to read you the story, and then you’ll listen to Felix on the tape.

11. Be omission: Bill was hidden by Martha/Bill hidden by Martha Bare stem: Bill was hidden by Martha/Bill was hide by Martha Be omission + Bare stem: Bill was hidden by Martha/Bill hide by Martha Semantic error: Bill was hidden by Martha/Martha was hidden by Bill [Item set: hide/hidden; catch/caught/ find/found; crush/crushed/ smash/smashed; forget/forgotten; hoot/shot; throw/thrown]

12. Outcomes

13. Study 1

14. Study 1

15. Study 1

16. Study 1

17. Study 1

18. Study 1

19. Conclusions from Study 1 • By 10 years of age, children in the SLI group comprehended reversible full verbal passives, showing knowledge of movement (A-chains)

20. By 10 years of age, children in the SLI group were more likely to accept omitted BE aux in passives than younger controls, but were accurate in rejecting bare stem violations (with or without BE omission) and were accurate in detecting semantic errors of erroneous theta role assignment (i.e, they knew movement was required). Thus, they did not make errors of semantic interpretation and they detected omissions of participial morphology, at the same time they continued to accept omissions of BE auxiliary.

21. By 10 years of age, children in the SLI group had outgrown their earlier period of TNS omission in simple declarative contexts

22. Study 2: Younger Children • Younger child participants 17 5-year-old SLI children 17 age-equivalent controls 16 3-year-old lexically- equivalent controls (PPVT raw scores)

23. Two tasks for younger children 1) Comprehension Stromswold’s 32-item task for reversible full passives, with toy animals. 2) TNS probe (3rd person –s, past –ed)

24. Outcomes for Study 2

25. Study 2

26. Study 2

27. Conclusions from Younger Children • At 5 years of age, children in the SLI group were below age peers in their comprehension of reversible full verbal passives, and similar to their younger lexically-equivalent peers • At 5 years of age, children in the SLI group performed significantly lower than their younger lexically equivalent peers in their performance on the TNS probe

28. General Interpretations • Children with SLI comprehend full passives by age 10, but at 5 years of age, passive acquisition seems to be delayed at a rate commensurate with younger children (~3 years of age). This suggests a delayed onset that is resolved at levels of general language growth similar to unaffected children (i.e., that the movement requirements of passives appear [mature] in the same way as is evident in unaffected children, just offset in age by a later start-up of the general language system in SLI).

29. Children with SLI show extended persistence of an EOI period, in their performance on grammaticality judgment tasks in which they are more likely than younger controls to accept omitted aux BE in passives, even at 10 years of age. The grammatical problem that underlies the EOI period in English (and other grammatical phenomena in other languages) persists as a marker of SLI for an extended period of time.

30. The outcomes are consistent with maturational models of passive acquisition (e.g., the A-chain deficit hypothesis of Borer & Wexler, 1987, 1992, and Babyonyshev et al., 2000). This hypothesis says that movement from object to subject positions (as in passive structures and unaccusative structures) is an operation that immature children consider ungrammatical

31. Several possible scenarios: • Very late maturation of finiteness (and anything else related to what underlies finiteness); • Everything that matures in unaffected children also matures late (if at all) in children with SLI;

32. A general language acquisition delay, in which maturational and learning mechanisms of language acquisition appear late but follow the same growth patterns as unaffected children (although at older ages), which can be combined with selective delays-within-a-delay in which certain grammatical properties show maturational delays beyond those of other properties of language acquisition (cf. Rice, in press; Wexler, in press).