Proceedings of the Annual Meeting of the Cognitive Science Society

This study examines the general claim that bilingualism leads to a facilitatory effect on cognitive control. Repeatedly resolving conflict between simultaneously active representations is thought to spill over into other domains involving conflict resolution. Recent literature indicates that the effects of bilingualism on executive functions need examination with a more comprehensive characterization of bilingualism and the use of multiple measures of executive control (Backer & Bortfeld, 2021; K. R. Paap & Greenberg, 2013). Here, we operationalize bilingualism as a set of continuous variables related to language knowledge and use. Next, we employ Bayesian regression analyses to assess the evidence for the null i.e., the lack of an effect of bilingualism. We aimed to address arguments in favor of an advantage that appeal to the measurement of bilingualism, task-specificity of the effect, and the methodological issues that exist with widely used tasks such as the Simon, Stroop or Flanker (K. R. Paap, Anders-Jefferson, Zimiga, Ma- son, & Mikulinsky, 2020). We assess the effects of bilingualism under a newly specified mechanism of attentional control (Bialystok & Craik, 2022), specifically in sustained attention. We administer new tasks, developed to be psychometrically sound and an improvement to existing measures of attentional control by Draheim, Tsukahara, Martin, Mashburn, and Engle. Two sustained attention tasks, along with two versions of the Flanker task were administered. The null model was the best model (with the greatest posterior probability) for all tasks. Bilingualism-related characteristics failed to show reliable influence for both sustained attention tasks. Even for ”improved measures” less susceptible to methodological flaws related to RT impurity and processing confounds, the best model was the null model. The results imply that the source of null effects is not the inadequate choice of inhibition as an explanatory mechanism. We conclude that bilingualism does not have coherent and consistent effects on cognitive control (specified as either inhibition or sustained attention) and the lack of an effect is not specific to the type of conflict involved in a task or its reliance on reaction times.