The present study aimed at investigating whether cognitive flexibility plays the same role in language switching as in task switching.

Cognitive flexibility (CF) of 52 low proficiency Chinese (L1)–English (L2) bilinguals was assessed by the Wisconsin Card Sorting Task. These bilinguals were then subdivided in 26 high- and 26 low-CF participants. Both groups performed a task-switching (Simon switch task) and a language-switching task (picture-naming task). The former task required participants to press a button congruent or incongruent to the pointing direction of an arrow, while in the latter participants had to name pictures in their L1 and L2.

Both response latencies and accuracy scores were obtained. Afterwards switch costs (i.e. longer latencies or reduced accuracy for switch in contrast to repeat trials) were calculated.

Results of the Simon switch task showed that switch costs for congruent and incongruent trials were symmetrical in the high-CF group, whereas the low-CF group showed larger switch costs for congruent than incongruent trials. Similarly, results of the language-switch task showed symmetrical switch costs for naming pictures in their L1 and L2 for the high-CF group, but L1 switch costs were larger than L2 ones in the low-CF group. These findings indicate that cognitive flexibility can modulate switch costs of two different switching tasks. This is in line with the inhibitory control model and the task-set inertia theory which assume that cognitive flexibility might modulate the symmetry of different types of switch costs via inhibition.

This study provides first direct evidence that cognitive flexibility plays a comparably important role in language switching as well as in task switching. Thus, cognitive flexibility can be beneficial for low proficiency bilinguals’ inhibitory control during task switching and language switching.