Language Control and Lexical Competition in Bilinguals: An Event-Related fMRI Study

TLDR

Language selection enables bilinguals to choose a language while suppressing interference, and prior work implicates multiple brain regions in this control. The study aimed to determine whether language selection depends on a language‑specific neural module or on general executive regions that also mediate switching between competing behavioral responses. Functional MRI was used to examine neural correlates of language selection in German‑French bilinguals during picture naming across monolingual and bilingual contexts. Bilingual context naming of the first language activated the left caudate and anterior cingulate cortex relative to monolingual contexts, with even greater activation when using a weaker second language, indicating that these regions support language control distinct from intralanguage task switching.

Abstract

Language selection (or control) refers to the cognitive mechanism that controls which language to use at a given moment and context. It allows bilinguals to selectively communicate in one target language while minimizing the interferences from the nontarget language. Previous studies have suggested the participation in language control of different brain areas. However, the question remains whether the selection of one language among others relies on a language-specific neural module or general executive regions that also allow switching between different competing behavioral responses including the switching between various linguistic registers. In this functional magnetic resonance imaging study, we investigated the neural correlates of language selection processes in German–French bilingual subjects during picture naming in different monolingual and bilingual selection contexts. We show that naming in the first language in the bilingual context (compared with monolingual contexts) increased activation in the left caudate and anterior cingulate cortex. Furthermore, the activation of these areas is even more extended when the subjects are using a second weaker language. These findings show that language control processes engaged in contexts during which both languages must remain active recruit the left caudate and the anterior cingulate cortex (ACC) in a manner that can be distinguished from areas engaged in intralanguage task switching.