Ecological Validity in Bilingualism Research and the Bilingual Advantage

Results of traditional language switching tasks have suggested that language switching is behaviorally effortful and requires increased involvement of cognitive control areas. Recent evidence has challenged this conclusion, showing that when bilinguals are allowed to switch languages freely, this cognitive effort and behavioral cost are either greatly reduced or completely eliminated. These findings show that switching languages is not inherently effortful, but rather particular circumstances and communicative demands may make it costly. The new evidence also challenges the basic premise of the hypothesis that bilingualism leads to executive control advantages due to frequent use of control mechanisms in language switching. We articulate a more nuanced, experience-dependent, version of this hypothesis, in which the advantage is limited to bilinguals who frequently switch languages based on external constraints. Traditional research in bilingualism has consistently found that switching languages is effortful, placing demands on neural systems of cognitive control. This finding runs counter to most bilinguals’ intuitive experience. We review a body of recent work showing that, in fact, when bilinguals switch languages voluntarily, both the behavioral cost of switching and the associated recruitment of cognitive control areas are greatly reduced or completely eliminated. This suggests that switching languages is not inherently effortful, but rather, particular communicative demands may make it costly. The new evidence also challenges the basic premise underlying the bilingual advantage hypothesis. We articulate a more nuanced version of it, in which the advantage is limited to bilinguals who frequently switch languages based on external constraints. Traditional research in bilingualism has consistently found that switching languages is effortful, placing demands on neural systems of cognitive control. This finding runs counter to most bilinguals’ intuitive experience. We review a body of recent work showing that, in fact, when bilinguals switch languages voluntarily, both the behavioral cost of switching and the associated recruitment of cognitive control areas are greatly reduced or completely eliminated. This suggests that switching languages is not inherently effortful, but rather, particular communicative demands may make it costly. The new evidence also challenges the basic premise underlying the bilingual advantage hypothesis. We articulate a more nuanced version of it, in which the advantage is limited to bilinguals who frequently switch languages based on external constraints. Commanding more than one language is the norm for the majority of the world’s population [1Craik F.I. Bialystok E. Cognition through the lifespan: mechanisms of change.Trends Cogn. Sci. 2006; 10: 131-138Abstract Full Text Full Text PDF PubMed Scopus (354) Google Scholar, 2US Census Bureau Statistical Abstract of the United States (2011) Languages Spoken at Home by Language: 2008, Table 53, US Census BureauGoogle Scholar], and multilingualism has been notably increasing in recent years [3Cenoz, J. et al. (2006) Benefits of linguistic diversity and multilingualism. Sustainable Development in a Diverse World (SUS. DIV) Position Paper, Research Task, 1, European Commission: Community Research and Development Information ServiceGoogle Scholar]. A remarkable feature of multilingual individuals is their ability to quickly and accurately switch back and forth between their different languages. Thus, multilingual individuals not only command each of their languages independently, but they are additionally able to alternate and coordinate the rules that govern each language. What are the mechanisms that allow bilingual individuals to effectively do this? How are these systems organized to achieve seamless transitions from one language to the other? Methodologically, these questions are not easy to answer as it is highly nontrivial to find reliable ways to elicit language switches on demand in the laboratory. To accomplish this, researchers have commonly devised rather artificial switching paradigms, in which bilingual individuals are asked to name a picture or a number in one or another language as prompted by an external cue displayed on the screen [4Meuter R.F. Allport A. Bilingual language switching in naming: asymmetrical costs of language selection.J. Mem. Lang. 1999; 40: Scopus Google Scholar, J. et switching in bilinguals as a of and Scopus Google Scholar, A. in bilingual evidence from language switching in highly bilinguals and Mem. Lang. Scopus Google Scholar, et control in and Scopus Google Scholar, E. 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