Poster A64, Thursday, August 16, 10:15 am – 12:00 pm, Room 2000AB
Neurodevelopmental impact of early bilingual acquisition on children’s syntactic processing
Neelima Wagley1, Frank Hu1, Alisa Baron2, James Booth3, Teresa Satterfield1, Lisa M. Bedore2, Ioulia Kovelman1;1University of Michigan, 2University of Texas - Austin, 3Vanderbilt University
How does bilingual acquisition influence children’s neural architecture for sentence processing? Language acquisition is characterized by progressive use of inflectional morphology marking verb tense and agreement (“Today he is baking a cake” or “Every day he bakes a cake”). Children’s acquisition of linguistic milestones is also linked to increased neural specialization of the left inferior frontal (IFG) and posterior temporal (pSTG) regions associated with language processing. We used functional Near-Infrared Spectroscopy (fNIRS) to investigate how bilingual exposure influences children’s cortical organization for processing morphosyntax. 65 Spanish-English bilingual children growing up in the U.S. (7-9 yo) judged English sentences with grammaticality violations in earlier- (verb agreement, -ing) and later-acquired (verb tense/agreement, -ed/s) omissions, or correct structures. Children had high dual-language proficiencies and were faster and more accurate when processing violations of the earlier- than the later-acquired structures. Task accuracy was related to greater English exposure. Neuroimaging analyses revealed robust activations along the dorsal route involved in syntactic processing: left IFG (BA 44) to the left pSTG and STS. Overall task accuracy and performance on a behavioral Spanish morphosyntax assessment significantly predicted brain activity during the grammaticality task in key frontal, temporal, and temporoparietal regions. The findings parallel those previously found for young monolingual children with earlier neural specialization of the left temporal regions, followed by increased specificity of the frontal regions (dorsal IFG regions) considered critical for syntactic processing. The findings suggest that early-exposed and highly proficient bilinguals may show a cumulative impact of dual-language exposure and use on the neural architecture for language processing.
Topic Area: Multilingualism