Reassessing the role of language dominance in n-2 language repetition costs as a marker of inhibition in multilingual language switching.

Speaking two or more languages shows bilingual flexibility, but flexible switching requires language control and often incurs performance costs. We examined inhibitory control assessing n-2 repetition costs when switching three languages (L1 [German], L2 [English], L3 [French]). These costs denote worse performance in n-2 repetitions (e.g., L2-L3-L2) than in n-2 nonrepetitions (e.g., L1-L3-L2), indicating persisting inhibition. In two experiments (n = 28 in Experiment 1; n = 44 in Experiment 2), n-2 repetition costs were observed, but only for L2. Looking into L2 trials specifically, we found n-2 repetition costs when switching back to L2 from the still weaker L3 but not when returning from the stronger L1, suggesting that L2 is a strong competitor for L3 (requiring L2 inhibition) but less so for L1. Finding n-2 repetition costs supports an inhibitory account of language control in general, but our study shows only partial evidence for the theoretically assumed more specific relation between language dominance and language inhibition (i.e., only for dominance relations with respect to L1 and L3 when switching back to L2). Taken together, the findings thus suggest the need for further refinement of the concept of language dominance and its relation to inhibition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).