Convergent cortical representation of semantic processing in bilinguals

This study examined whether semantic processes in two languages (English an d Spanish) are mediated by a common neural system in fluent bilinguals who acquired their second language years after acquiring their first language. Functional magnetic resonance imaging was performed while bilingual partici pants made semantic and nonsemantic decisions about words in Spanish and En glish. There was greater activation for semantic relative to nonsemantic de cisions in left and right frontal regions, with greater left frontal activa tion. The locations of activations were similar for both languages, and no differences were found when semantic decisions for English and Spanish word s were compared directly. These results demonstrate a shared frontal lobe s ystem for semantic analysis of the languages and are consistent with cognit ive research on bilingualism indicating that the two languages of a bilingu al person access a common semantic system. (C) 1999 Academic Press.