Abstract
The present review focuses on event-related potential (ERP) studies that have addressed two fundamental issues in bilingualism research, namely the processing of a first versus a second language in the bilingual brain and the issue of control of two languages. A major advantage of the ERP technique is its high temporal resolution that enables the study of task-related neural activity at the millisecond level. For example, ERP studies of bilingualism have shown that developmental changes in the ability to discriminate native and foreign speech sounds can experimentally be traced by the presence or absence of a specific ERP component (the mismatch negativity). They have also revealed latency delays in a semantic-related ERP component (the N400) in bilinguals compared to monolinguals, as well as in bilinguals reading in their L1 or L2 language. These studies have also highlighted the importance of L2 proficiency level and age of acquisition on bilingual language processing. Moreover, ERP studies have pointed out potential mechanisms of avoidance of interference between languages (the NoGo N200 effect). The present review aims to describe and integrate the main results of the selected ERP studies on bilingualism and to provide an overview of how different ERP components can be used to address important theoretical questions in this field. Finally, we suggest potential research directions to clarify unresolved issues and to advance this emerging field of research.