ABSTRACT
This chapter discusses the research field on bilingualism and its purported effects on cognition, both for children and across the lifespan. It explores some of the factors behind the conflicting and often contradictory results and interpretations. The chapter also discusses the contributions of neuroscience to the debate thus far and identify future opportunities in the field of research. The implications of bilingualism in education also extend beyond English as an additional language. There is the question of when best to introduce the acquisition of additional languages. Numerous studies, both behavioural and neuroimaging, have yielded at best inconsistent and at worst contradictory results. The reasons for some of these inconsistent results have been explained already. A critical but unresolved issue, therefore, is how multi-linguistic experience impacts on crucial cognitive processes across the lifespan, from infancy to old age. Neuroscience has helped to identify the regions of the brain associated with both the language representation and other non-linguistic cognitive activity in bilinguals.
