The Differential Role of Executive Functions in the Cognitive Control of Language Switching

Studies of bilingual speech production suggest that different executive functions (EFs) contribute to the cognitive control of language production. However, no study has simultaneously examined the relationship between different EFs and language control during online speech production. The current study examined individual differences in three EFs (working memory updating, inhibitory control, and task-set switching) and their relationship with performance in a trilingual language-switching task for a group of forty-seven native English (L1) speakers learning French (L2) and Spanish (L3). Analyses indicate complex interactions between EFs and language switching: better inhibitory control was related to smaller L1 switch costs, whereas better working memory was related to larger L1 switch costs. Working memory was also related to larger L2 switch costs, but only when switching from L1. These results support theories of cognitive control that implicate both global and local control mechanisms, and suggest unique contributions of each EF to both global and local cognitive control during language switching. Finally, we discuss the implications for theories of multilingual language control.