One consequence of globalization, or the increased interconnectedness and interdependence of peoples and countries, is that speaking more than one language is now the norm worldwide. Because of this worldwide prevalence, the bilingual mind has increasingly become an important topic of study in cognitive science and has generated a unique set of questions: Are the two languages represented in separate systems? Do interactions between languages facilitate or hinder language comprehension and production? How does the bilingual speaker select a target language and avoid the nontarget language?

Early research investigating the effects of bilingualism on language and cognitive processing concluded that knowledge of more than one language results in disadvantages in every aspect of cognition. This entry reviews a large body of research that demonstrates that bilingualism ...