Role of top-down language control in bilingual production and comprehension: Evidence from induced oscillations

Abstract

Aims: The present study was designed to investigate the role of language control during simultaneous production and comprehension. Design: Participants completed a set of language background and cognitive skills questionnaires and were randomly divided into pairs. Then, the pairs of participants were asked to finish a joint language switching task while their electroencephalogram was recorded. When one participant was naming pictures, the other one was listening. The language to be used in each trial was specified by cues. Data and Analysis: Response latencies were obtained. An analysis was conducted on induced oscillations in a cue-locked period and a stimulus-locked period. Findings: An analysis of induced oscillations showed that production and comprehension exhibited different delta and theta oscillations, suggesting that cross-modality interference may be caused by joint language switching, and bilinguals employed different degrees of language control in comprehension and production. Furthermore, the cross-person condition exhibited stronger oscillations than the within-person condition, indicating that joint language switching involves cross-person interference and that bilinguals use additional oscillations to inhibit such interference. Importantly, the stimulus-locked period showed larger delta and theta oscillations in second language switch trials than in first language switch trials in the within-person condition, indicating that delta and theta may index the inhibition of cross-language interference. Originality: The current study revealed the top-down language control mechanism by analysing induced oscillations, which reflected a mainly cognitively driven process. Significance: Bilinguals’ language control might be used to inhibit complex interference during daily life.