Verb agreement in Turkish-Dutch bilingual children with SLI Jan de Jong, Antje Orgassa, Nazife Çavuş, Anne Baker, Fred Weerman

Research issue Verb morphology is vulnerable in SLI. Explanations: locus of the problem either in representation or processing Explanations are based on crosslinguistic differences or commonalities in symptoms Are crosslinguistic differences found when the subjects are the same (bilingual) children? Which theory explains the symptoms best? Mention that crosslinguistic evidence shows this clearly for some languages and not so clearly for others.

Outline of the talk Two theories of SLI Characteristics of Dutch and Turkish Predictions for SLI in two languages: Dutch and Turkish The Dutch study The Turkish study Comparing the results from both studies Conclusions

SLI in Turkish and Dutch: two theories on SLI will be tested SLI is a representational deficit Agreement Deficit hypothesis (Clahsen) SLI is a processing deficit Sparse morphology hypothesis (Leonard)

Characteristics of Dutch and Turkish Agreement is marked Pro-drop Non-pro-drop Inflectional paradigm uniform Inflectional paradigm not uniform Rich morphology Sparse morphology

SLI in Turkish and Dutch: what do theories on SLI predict? Agreement Deficit hypothesis Agreement problems will be found in both languages Sparse morphology hypothesis Morphological problems will be more serious in Dutch than in Turkish

Possible outcomes and their interpretation Turkish – / Dutch – Agreement deficit hypothesis supported Turkish + / Dutch – Turkish – / Dutch + Turkish + / Dutch + Need to explain what the meaning of plus and minus is – here at this moment in the talk.

Possible outcomes and their interpretation Turkish – / Dutch – Agreement deficit hypothesis supported Turkish + / Dutch – falsified Turkish – / Dutch + Turkish + / Dutch +

Possible outcomes and their interpretation Turkish – / Dutch – Agreement deficit hypothesis supported Turkish + / Dutch – Sparse morphology hypothesis falsified Turkish – / Dutch + Turkish + / Dutch +

Possible outcomes and their interpretation Turkish – / Dutch – Sparse morphology hypothesis falsified Agreement deficit hypothesis supported Turkish + / Dutch – Turkish – / Dutch + Turkish + / Dutch +

Possible outcomes and their interpretation Turkish – / Dutch – Sparse morphology hypothesis falsified Agreement deficit hypothesis supported Turkish + / Dutch – Turkish – / Dutch + Turkish + / Dutch + neither falsified nor supported Need to explain what factors can influence both languages having high scores

Subjects Bilingual SLI 20 7;4 5;11 – 8;5 Turkish & Dutch Group Number Average Age Age range Data from: Bilingual SLI 20 7;4 5;11 – 8;5 Turkish & Dutch Bilingual typical 7;1 5;9 – 8;4 Beperking/voorzicht in matching: not same children in bi-typical

The Dutch study: Inflectional paradigm context suffix lezen ‘to read’ 1sg stem + ø ik lees ‘I read’ 2sg stem + t jij leest ‘you read’ 3sg hij/ zij leest ‘he/ she reads’ 1pl-3pl stem + en wij/ jullie/ zij lezen ‘we/ you/ they read’ Finite paradigm for regular verbs in present indicative Verb-subject agreement in Dutch declaratives (main & embedded clause)

The Dutch study: Task ilustration Antje leest een boek en Jan leest een krant Antje reads-3sg a book and Jan reads-3sg a newspaper

The Dutch study: Results - correctness Verb inflection (%) Bilingual Typical 88 (303) Bilingual SLI 77 (250)

The Dutch experiment: conclusions Children with SLI produce more incorrect forms than children without SLI in their L2

The Turkish study: inflectional paradigm context suffix okumak ‘to read’ -dI- (PAST evidenced) 1 sg stem + dI + m Oku-du-m ‘I read’ 2 sg stem + dI + n Oku-du-n ‘you read’ 3 sg stem + dI + Ø Oku-du- Ø ‘he/ she read’ 1 pl stem + dI + k Oku-du-k ‘we read’ 2pl stem + dI + nuz Oku-du-nuz ‘you read’ 3 pl stem + dI + lar Oku-du-lar ‘they read’

The Turkish study: task illustration Anne ben portakal-ı _____ (sık-tı-m). Mummy I orange-ACC ____ (press-PST.DI-1SG) Mummy, I have squeezed an orange.

The Turkish study: Results - correctness Verb inflection (%) Bilingual Typical 100 (251) Bilingual SLI 93 (295)

Turkish The Turkish study Children with SLI produce more incorrect forms than children without SLI in their L1

Turkish versus Dutch: correctness (%) Bilingual typical 100 88 Bilingual SLI 93 77

Turkish versus Dutch: conclusion for the group More errors in Dutch than in Turkish Crosslinguistic difference The Sparse Morphology hypothesis is confirmed The Agreement Deficit hypothesis is disconfirmed

Comparing the individual patterns within the SLI group (+ = >90% correct) Turkish –/ Dutch – n = 3 Turkish +/ Dutch - n = 12 Turkish –/ Dutch + n = 2 Turkish +/ Dutch +

Explaining the individual patterns within the SLI group (+ =>90% correct) Turkish –/ Dutch – n = 3 Supports Missing Agreement hypothesis Turkish +/ Dutch - n = 12 Turkish –/ Dutch + n = 2 Turkish +/ Dutch + But 17 that falsify MAH

Explaining the individual patterns within the SLI group (+ =>90% correct) Turkish –/ Dutch – n = 3 Supports Missing Agreement hypothesis Turkish +/ Dutch - n = 12 Supports Sparse Morphology hypothesis Turkish –/ Dutch + n = 2 Turkish +/ Dutch + BUT 5 that falsify SMH and 3 not clear

Explaining the individual patterns within the SLI group (+ =>90% correct) Turkish –/ Dutch – n = 3 Supports Missing Agreement hypothesis Turkish +/ Dutch - n = 12 Supports Sparse Morphology hypothesis Turkish –/ Dutch + n = 2 Differential input from two languages (D>T) Turkish +/ Dutch + 2 children falsify both hypothesis – alternative explnation

Explaining the individual patterns within the SLI group (+ =>90% correct) Turkish –/ Dutch – n = 3 Supports Missing Agreement hypothesis Turkish +/ Dutch - n = 12 Supports Sparse Morphology hypothesis Turkish –/ Dutch + n = 2 Differential input from two languages (D>T) Turkish +/ Dutch + 3 children do not falsify Sparse Morphology but alternative explnation

Explaining the individual patterns within the SLI group (+ =>90% correct) Turkish –/ Dutch – n = 3 Supports Missing Agreement hypothesis Turkish +/ Dutch - n = 12 Supports Sparse Morphology hypothesis Turkish –/ Dutch + n = 2 Differential input from two languages (D>T) Turkish +/ Dutch + Misdiagnosis? 3 children do not falsify Sparse Morphology but alternative explnation

Conclusions The crosslinguistic differences in the group comparison support processing-based explanations like the Sparse morphology hypothesis and do not support the Agreement Deficit hypothesis The individual patterns support processing-based explanations like the Sparse morphology hypothesis and do not support the Agreement Deficit hypothesis The individual differences also highlight the importance of considering L2 factors (like language input, language dominance) in understanding bilingual SLI Only two children who perhaps have an agreement deficit – possible after all! Majoirty seem to have Processing problem. Answer does not have to be absolute

What about the typical bilingual group? (+ = >90% correct) Turkish –/ Dutch – n = 0 Turkish +/ Dutch - n = 8 Supports Sparse Morphology hypothesis? Differential input from two languages (T>D)? Turkish –/ Dutch + Turkish +/ Dutch + n = 12