Bilingual switching between languages and listeners: Insights from immersive virtual reality

Perhaps the main advantage of being bilingual is the capacity to communicate with interlocutors that have different language backgrounds. In the life of a bilingual, switching interlocutors hence sometimes involves switching languages. We know that the capacity to switch from one language to another is supported by control mechanisms, such as task-set reconfiguration. This study investigates whether similar neurophysiological mechanisms support bilingual switching between different listeners, within and across languages. A group of 48 unbalanced Dutch-English bilinguals named pictures for two monolingual Dutch and two monolingual English life-size virtual listeners in an immersive virtual reality environment. In terms of reaction times, switching languages came at a cost over and above the significant cost of switching from one listener to another. Analysis of event-related potentials showed similar electrophysiological correlates for switching listeners and switching languages. However, it was found that having to switch listeners and languages at the same time delays the onset of lexical processes more than a switch between listeners within the same language. Findings are interpreted in light of the interplay between proactive (sustained inhibition) and reactive (task-set reconfiguration) control in bilingual speech production. It is argued that a possible bilingual advantage in executive control may not be due to the process of switching per se. This study paves the way for the study of bilingual language switching in ecologically valid, naturalistic, experimental settings.