Language athletes: Dual-language code-switchers exhibit inhibitory control advantages

Abstract

Recent studies have begun to examine bilingual cognition from more nuanced, experienced-based perspectives. The present study adds to this body of work by investigating the potential impact of code-switching on bilinguals' inhibitory control abilities. Crucially, our bilingual participants originated from a predominantly dual-language environment, the interactional context which is believed to require (and therefore, potentially train) cognitive control processes related to goal-monitoring and inhibition. As such, 266 French Canadian bilinguals completed an online experiment wherein they were asked to complete a domain-general (Flanker) and a language-specific (bilingual Stroop) inhibitory control task, as well as extensive demographic and language background questionnaires. Stepwise multiple regressions (including various potential demographic and linguistic predictors) were conducted on the participants' Flanker and Stroop effects. The results indicated that the bilinguals' propensity to code-switch consistently yielded significant positive (but unidirectional) inhibitory control effects: dual-language bilinguals who reported more habitual French-to-English switching exhibited better goal-monitoring and inhibition abilities. For the language-specific task, the analysis also revealed that frequent unintentional code-switching may mitigate these inhibition skills. As such, the findings demonstrate that dual-language code-switchers may experience inhibitory control benefits, but only when their switching is self-reportedly deliberate. We conclude that the bilinguals' interactional context is thus of primary importance, as the dual-language context is more conducive to intentional code-switching. Overall, the current study highlights the importance of considering individualistic language experience when it comes to examining potential bilingual executive functioning advantages.

Keywords: adaptive control hypothesis; bilingualism; code-switching; executive function; inhibitory control; interactional context.

Figure 1

(A) Individual variation in code-switching habits (BSwQ components; Rodriguez-Fornells et al., 2012) for all participants. (B) Individual variation in the language entropy statistic and proportion of bilingual interactions for all participants. An entropy value of 0 signifies complete linguistic compartmentalization; 1 indicates complete linguistic integration (Gullifer and Titone, 2020). For each variable, the thick black line represents the median, the outline of the box represents the inter-quartile range, the whiskers of the boxplot represent the maximum and minimum values, and the violin outline illustrates the density of the data.

Figure 2

Procedure for the Flanker (A) and Stroop (B) tasks. Both the single-language and bilingual blocks are depicted for the Stroop task.

Figure 3

(A) Individual variation in the Facilitation effect (neutral—congruent trials) for both tasks. (B) Individual variation in the Inhibition effect (neutral—incongruent trials) for both tasks. For each variable, the thick black line represents the median, the outline of the box represents the inter-quartile range, the whiskers of the boxplot represent the maximum and minimum values, and the violin outline illustrates the density of the data. Note that for the inhibition effect, negative is plotted up.

Figure 4

(A) Visualization of the significant predictor for the Flanker facilitation effect (top) and inhibition effect (bottom). (B) Visualization of the significant predictors for the Stroop facilitation effect (top) and inhibition effect (bottom). The shaded areas surrounding the regression line represent the standard error of the regression. Note that for inhibition effects, negative is plotted up.