Paths to characterizing typical and atypical bilingual language development
The realization of appropriate clinical tools for bilingual children rests on an increasingly accurate understanding of bilingual language development. To enhance our understanding of bilingualism, this dissertation investigates typical and atypical bilingual language development under two complementary perspectives. The first approach, a single-language focus, emphasizes careful measurement of performance in a single language to identify clinical tools and establish benchmarks that are appropriate for bilingual children. The second approach, the uniquely bilingual lens, leverages patterns of language use that are specific to the experience of dual language exposure, including cross-language interactions, to support the creation of clinical tools that are tailored to bilingual speakers. Taken together, these approaches allow for a more comprehensive picture of language development in young bilinguals.
Consistent with a single-language focus, Chapters 2 and 3 utilize measures derived from language samples to characterize young bilinguals’ use of English tense and agreement marking, a grammatical feature that is challenging for typically developing children and particularly challenging for children with atypical language development. Participants included Spanish-English bilingual children recruited at a time when language assessment is common, their preschool year. Across these studies, results indicated that clinically relevant information for bilingual children may be obtained from single-language measures provided that the measure is well-matched to the child’s level of language development and that comparisons are made with care (i.e., bilingual children are compared to bilingual children).
Chapters 4 and 5 investigate cross-language interactions in Spanish-English bilingual preschoolers, consistent with the uniquely bilingual lens. Results in Chapter 4 demonstrate that young bilinguals may be sensitive to cognates (e.g., elephant/elefante in English/Spanish), thus demonstrating patterns of cross-language interactions that are widely documented in adult bilinguals. Chapter 5 extends this work to investigate whether Spanish-English bilingual preschoolers with varying levels of language ability demonstrate cognate sensitivity as they encounter novel words in each language. Findings from off-line accuracy measures and fixation patterns indicate that cross-language interactions in development are linked to multiple factors, including language dominance, task requirements and, potentially, language ability.