Typical and atypical language development in Turkish-Swedish bilingual children aged 4–7

Sammanfattning: This thesis investigates the vocabulary and narrative macrostructure skills of 102 typically-developing (TD) 4- to 7-year-old Turkish-Swedish bilingual children (cross-sectional), the development of these skills over time from age 4 to 6 in a subgroup of 10 children (longitudinal), and six Turkish-Swedish children with a language impairment (LI) diagnosis (clinical). The children’s health, family and language backgrounds, their language use and input patterns are explored through parental questionnaires, family interviews, and interviews with teachers and speech-language pathologists. In both Turkish and Swedish, comprehension and production are assessed with comparable materials: Cross-Linguistic Lexical Tasks (CLT; Haman et al., 2015), and Multilingual Assessment Instrument for Narratives (MAIN; Gagarina et al., 2012). For vocabulary (CLT), age development, language differences (Turkish vs. Swedish), differences between comprehension and production, and effects of language use and input are explored. For narrative macrostructure (MAIN), age development, language differences and task differences (Cat/Dog vs. Baby Birds/Baby Goats) are analyzed. LI children’s scores are compared with TD children, with additional focus on the LI children’s communicative, linguistic and social behavior. In both vocabulary comprehension and production, the youngest TD groups performed better in Turkish than in Swedish, but by age 6, Turkish and Swedish vocabulary scores matched due to rapid improvement in Swedish. Factors related to vocabulary scores were: daily language input, parents’ language use with each other and with the child, and child’s language with the sibling(s). For narratives, comprehension was ahead of production. There was no difference between Turkish and Swedish MAIN comprehension, but for both languages a task effect was found (higher scores on Cat/Dog than Baby Birds/Baby Goats). Narrative production scores were generally low for both languages, but increased more with age in Swedish than in Turkish. The longitudinal study largely confirmed the patterns found in the cross-sectional data.The majority of the LI children performed far below their TD peers in both their languages. Some LI children performed very low in only one language, despite extensive and long-term exposure to that language. In contrast, TD children with very low scores in one language usually had very limited exposure to that language. LI children were also reported to have difficulties with word learning, pragmatics, and attention, and a family history with language problems. It is suggested that bilingual children with potential language impairment should be assessed holistically in both their languages and extensive information about their family backgrounds and language input characteristics be collected.