Bilingual Experience and Resting-State Brain Connectivity: Impacts of L2 Age of Acquisition and Social Diversity of Language Use on Control Networks

Publication date: Available online 1 May 2018 Source:Neuropsychologia Author(s): Jason W. Gullifer, Xiaoqian J. Chai, Veronica Whitford, Irina Pivneva, Shari Baum, Denise Klein, Debra Titone We investigated the independent contributions of second language (L2) age of acquisition (AoA) and social diversity of language use on intrinsic brain organization using seed-based resting-state functional connectivity among highly proficient French-English bilinguals. There were two key findings. First, earlier L2 AoA related to greater interhemispheric functional connectivity between homologous frontal brain regions, and to decreased reliance on proactive vs. reactive executive control in an AX-Continuous Performance Task completed outside the scanner. Second, greater diversity in social language use in daily life related to greater connectivity between the anterior cingulate cortex and the putamen bilaterally, and to increased reliance on proactive control in the same task. These findings suggest that early vs. late L2 AoA links to a specialized neural framework for processing two languages that may rely on a specific type of executive control (i.e., reactive control). In contrast, higher vs. lower degrees of diversity in social language use link more to a broadly distributed set of brain networks implicated in another type of executive control (i.e., proactive control) and context monitoring.
Source: Neuropsychologia - Category: Neurology Source Type: research