A comparison of structural brain differences in monolingual and highly proficient multilingual speakers

Abstract Structural and functional brain adaptations in bilingual speakers are well documented the neurolinguistic literature. However, far less is known about neural changes evidenced multilingual speakers. This study investigates plasticity a group of highly proficient multilinguals, fluent four or more languages, compared to monolinguals. An ROI analysis used evaluate differences core linguistic regions associated with language control revealed robust decreases for multilinguals grey matter thickness two within parietal lobe (i.e., precuneus angular gyrus), involved lexico-semantic processing, memory retrieval, maintenance. We discuss our findings context emerging models characterizing trajectorial structures experience. consider how demands optimal functioning multi-linguistic environments may foster cortical that manifest as decreased GM