Is there electrophysiological evidence for a bilingual advantage in neural processes related to executive functions?

Over the last two decades, a large number of studies have concluded that bilingualism enhances executive functions. However, other studies have reported no significant results. In addition, it is not clear how bilingualism might modulate specific executive control processes. Event-related potentials (ERP) are an excellent technique for identifying whether the neural correlates of executive control processes are strengthened by bilingualism, given their high temporal resolution. On the basis of previous research into the ERP correlates of executive functions, we hypothesize that specific ERP differences between monolinguals and bilinguals can be considered to indicate a bilingual advantage in executive functions. We then review the very limited number of studies that have investigated ERP differences between monolinguals and bilinguals during the performance of executive control tasks. Overall, we conclude that the existence of a bilingual advantage in neural processing related to executive functions remains uncertain and further studies are required. We highlight the utility of investigating several ERPs that have been ignored by previous studies.