Genetic bases of language control in bilinguals: Evidence from an EEG study

Abstract

Previous studies have debated whether the ability for bilinguals to mentally control their languages is a consequence of their experiences switching between languages or whether it is a specific, yet highly-adaptive, cognitive ability. The current study investigates how variations in the language-related gene FOXP2 and executive function-related genes COMT, BDNF, and Kibra/WWC1 affect bilingual language control during two phases of speech production, namely the language schema phase (i.e., the selection of one language or another) and lexical response phase (i.e., utterance of the target). Chinese–English bilinguals (N = 119) participated in a picture-naming task involving cued language switches. Statistical analyses showed that both genes significantly influenced language control on neural coding and behavioral performance. Specifically, FOXP2 rs1456031 showed a wide-ranging effect on language control, including RTs, F(2, 113) = 4.00, FDR p =.036, and neural coding across three-time phases (N2a: F(2, 113) = 4.96, FDR p =.014; N2b: F(2, 113) = 4.30, FDR p =.028, LPC: F(2, 113) = 2.82, FDR p =.060), while the COMT rs4818 (ts >2.69, FDR ps 5.31, FDR ps −3.29, FDR ps