Research on the effects of bilingualism and multilingualism on executive function has yielded conflicting results over the past decade. Addressing the issue, scholars have made significant advancements in methodological approaches. Yet, the operationalization and analysis of language proficiency, one of the major components of linguistic background, remain unsystematized. This study investigated how various measures of language proficiency and fluency differ in their ability to predict executive function performance in shifting. The Adaptive Control Hypothesis was the framework that motivated the study, with additional analysis of the effects of language proficiency and fluency as independent and interacting variables. The results from 68 Hungarian-English bilinguals showed that only performance in the category fluency task significantly predicted executive function abilities, and only when interacting with levels of engagement in interactional contexts. The study also highlighted that proficiency and fluency are related but not interchangeable constructs; however, further investigations and strict operationalization of the two concepts are necessary to understand the relation between interactional contexts and executive function.Disclosure Statement The authors reported no potential conflict of interests.

Eredeti fellelhetőség: eejpl.vnu.edu.ua