1. A. Baker, J. de Jong, A. Orgassa & F. Weerman Collaborators: VARIFLEX project: Elma Blom & Daniela Polišenská (NWO-research grant 254-70-010: Disentangling bilingualism and specific language impairment (BISLI)) Verbal inflection: why is it vulnerable in SLI?

2. Contents Overview of theories Data relevant to the various theories - from Turkish - from Dutch Discussion & Conclusions

3. OVERVIEW OF THEORIES

4. Linguistic theories Agreement deficit account: Missing knowledge of the system underlying agreement relations. Lack of access to UG. (e.g. Clahsen 1989, 1993, 2008; van der Lely 1998, 2005) Predictions SLI children will make numerous errors. Previous data Great variation across languages. Some languages barely show verb inflection problems in SLI. Possibly only part of the paradigm affected? (Clahsen 2008)

5. Linguistic theories Procedural deficit account: problem in procedural memory (Ullman & Pierpoint 2005) Predictions SLI children will make similar errors to adult L2 learners since they are relying on declarative memory. Data Monolingual Dutch SLI children make different errors to L2 learners of Dutch. (de Jong 1999; Blom et al. 2006) Unlikely?

6. Processing theories Surface hypothesis Sparse morphology hypothesis (e.g. Leonard 1998, 2000, 2009) Predictions More problems with phonetically non- salient morphemes and those that are semantically less transparent. More problems in languages with poor morphology. Data e.g. Italian and Hebrew better than English. But total explanation? (de Jong 1999; Blom et al. 2006)

7. Processing theories Vulnerability feature hypothesis (e.g. Bishop 1994) Predictions Performance limitations such as sentence length or phonological complexity will negatively affect the application of the rule. Data Evidence of effects from naturalness of tokens, complexity of task. (Coady et al. 2007; Gillam et al. 2002)

8. Processing theories General slowing hypothesis for bilingual SLI (e.g. Paradis et al. 2005, 2006, 2007) Predictions Delay compared to monolingual SLI children. Data But no evidence of delay in simultaneous bilinguals. Sequential bilinguals?

9. METHOD

10. Research variables Turkish: verb inflectional agreement Dutch: verb inflectional agreement Grammatical closure procedures used Turkish: past tense dI, 1st, 2nd, 3rd sing. Dutch: present 1st, 2nd, 3rd sing.; 1st, 2nd pl. Dutch: tested in main clauses (SVO, OVS) and subordinate clauses (SOV)

11. Overview populations GroupsNAge range (x) Onset Dutch exposure Length Dutch exposure L1-TD204;0-5;11 (4;4)0 yrs58 months L1-SLI256;1-7;12 (7;3)0 yrs87 months L2-TD206;7-7;11 (7;3)1-4 yrs63 months L2-SLI206;8-8;3 (7;5)1-4 yrs62 months Adult L2918-31 (23)> 15 yrsca. 120 months

12. RESULTS

13. Comparing Turkish and Dutch Percentage accuracy verb inflection in main clauses

14. Comparing Turkish and Dutch Percentage accuracy verb inflection in main clauses Significant SLI effect in both languages BUT Turkish better than Dutch Support for the Sparse Morphology Hypothesis.

15. Comparing Turkish and Dutch Percentage accuracy verb inflection in main clauses Significant SLI effect in both languages BUT Turkish better than Dutch Support for the Sparse Morphology Hypothesis. Accuracy rate is high in both languages. Too high for a general agreement deficit to be plausible

16. Verb inflection – error types in Dutch

17. -en Significant difference between adult L2 and all child groups. Adults use more -en). No support for Procedural Deficit hypothesis.

18. Verb inflection – error types in Dutch Percentage of substitution errors

19. Verb inflection – error types in Dutch No part of paradigm particularly vulnerable. No support for Clahsen’s 2008 suggestion. Percentage of substitution errors

20. L2 effect in Dutch? Percentage accuracy verb inflection in main clauses

21. L2 effect in Dutch? Percentage accuracy verb inflection in main clauses No significant L2 effect No support for the General Slowing Hypothesis. Four years of input has been sufficient to learn the rule (fairly) well.

22. Comparing main clauses and subordinate clauses in Dutch NB 3rd pers. sing. only Percentage accuracy in main and sub. clauses

23. Comparing main clauses and subordinate clauses in Dutch NB 3rd pers. sing. only Percentage accuracy in main and sub. clauses Significantly higher accuracy in subordinate clauses. Accuracy so high that rule must have be learned. Movement rule in main clauses is a source of complexity for all learners. Support for the Vulnerability Feature Hypothesis.

24. Avoidance of inflectional contexts Percentage response types in V2 sentences

25. Avoidance of inflectional contexts Percentage response types in V2 sentences Dummy auxiliaries and Root Infinitives require no verb movement. Evidence of avoidance of these contexts where inflection has to be used. Support for the Vulnerability Feature Hypothesis.

26. DISCUSSION AND CONCLUSIONS

27. What is vulnerable? Distinction necessary between learning the verb inflection rule and applying it. Word order is not highly problematic (Orgassa 2009) Computing two operations is problematic and results in: - avoidance of the V2 order - errors in inflection What causes problems with computation?

28. Possible model of factors influencing vulnerability of verb inflection

29. Bilingualism

30. Thank You!

31. How about other agreement rules? Percentage accuracy in verb and adjectival inflection in Dutch

32. Verb inflection in Dutch contextsuffix lezen (to read) 1SGstem + ø ik lees (I read) 2SGstem + tjij leest (you read) 3SGstem + thij/zij leest ( he/she read) 1PL - 3PLstem + enwij/jullie/zij lezen (we/you/they read)

33. Method – verb inflection Zij leest een boek enhij leest de krant (She reads a book andhe reads a newspaper) Controlled elicitation – sentence completion