Electrophysiological evidence for domain-general inhibitory control during bilingual language switching.

Huanhuan Liu,Baoguo Chen,Huixia Zhou,Sonja Rossi,J Bruce Morton

doi:10.1371/journal.pone.0110887

Abstract

This paper presents an experiment that explored the role of domain–general inhibitory control on language switching. Reaction times (RTs) and event–related brain potentials (ERPs) were recorded when low–proficient bilinguals with high and low inhibitory control (IC) switched between overt picture naming in both their L1 and L2. Results showed that the language switch costs of bilinguals with high–IC were symmetrical, while that of bilinguals with low–IC were not. The N2 component failed to show a significant interaction between group, language and task, indicating that inhibition may not comes into play during the language task schema competition phase. The late positive component (LPC), however, showed larger amplitudes for L2 repeat and switch trials than for L1 trials in the high–IC group, indicating that inhibition may play a key role during the lexical response selection phase. These findings suggest that domain–general inhibitory control plays an important role in modulating language switch costs and its influence can be specified in lexical selection phase.

Highlights

Switching between languages can sometimes cause processing delays, which is referred to as the so–called ‘‘switch costs’’
The main finding of the behavioral results was that the high–IC group showed symmetrical language switch costs, whereas the low–IC group showed asymmetrical switch costs, indicating that domain–general inhibitory control seems to play an important role in modulating language switch costs
The event–related brain potentials (ERPs) results concerning the N2 component failed to show a significant interaction between group, language, and task, while the late positive component (LPC) revealed such a three–way interaction, indicating that inhibition may play a key role during the lexical response selection phase

Summary

Introduction

Switching between languages can sometimes cause processing delays, which is referred to as the so–called ‘‘switch costs’’. The model argued that the degree of inhibition for language is positively correlated with language proficiency and the reactivation of a suppressed language is positively correlated with the degree of inhibition. This means that a dominant language needs to recruit a more laborious inhibition and reactivation. Due to the high inhibition needed to suppress a dominant L1 in the previous trial when switching from L1 to L2, participants spend more time in relieving the inhibition when switching from L2 to L1, leading to larger switch costs from L2 to L1 than vice versa. Evidences from behavioral experiments have been taken as support for the IC model [1,2,3], [6]

Methods

Results

Conclusion