Chapter 13. Bilingualism and executive function

This chapter examines the idea that much of the confusion and contradictory evidence about the relation between bilingualism and executive function can be traced to an over-simplification of the two main terms. Using more nuanced definitions for “bilingualism” and “executive function”, research examining the effect of bilingualism on cognition in infancy, childhood, and adulthood is reviewed. The sum of the evidence is then used to attempt to extract a common “mechanism” for the diverse effects that is consistent with a broader definition of the main concepts of bilingualism and executive function. The conclusion is that a continuous notion of “executive attention” in which there is a linear relation between degree of bilingualism and degree of executive function demands provides a good fit with the empirical evidence and a plausible explanation for the modifications found in the brain and behavior of bilinguals across the lifespan.