Executive function skills in English monolinguals and Mandarin-English bilinguals

Abstract

Previous studies report mixed evidence regarding bilinguals’ cognitive advantage in inhibition and other executive function (EF) tasks compared to monolinguals. This study aims to replicate previous research on Mandarin-English bilinguals. Forty-four participants (22 English monolinguals & 22 Mandarin-English bilinguals) were recruited to complete four EF tasks: Simon, Stroop, Letter-Number Switching and Color-Shape Switching (Cued), targeting inhibition and attention shifting skills. Dependent measures included reaction time (RT) and percentage accuracy (PA). In the Simon task, bilinguals responded significantly slower overall than monolinguals, although there was a significantly larger difference in RT between compatible vs. incompatible trials in monolinguals. The Stroop task revealed no group differences or interaction effects. For the switching tasks, bilinguals had a significantly higher PA overall than monolinguals in the Letter-Number Switching task with no significant group differences found in RT. No significant group differences were found in either measures for the Color-Shape Switching (Cued) task. Weak evidence of enhanced EF skills were reported in Mandarin-English bilinguals. Topics discussed include: choice of dependent measures, choice of cognitive tasks, controlling for confounding variables, and task formats. Future studies should focus on refining experimental design and better defining bilingualism to inform future clinical decisions for bilinguals with executive function-related impairments.