Cognitive efficiency and expertise-dependent automaticity in the working memory performance of bilinguals

Brain and Cognition. 2025. Vol. 187. Article 106308.

Federico Gallo, Liliia Terekhina, Jubin Abutalebi, Yury Shtyrov, Andriy Myachykov

The concepts of cognitive efficiency (CE) and expertise-dependent automaticity are central to the understanding of cognitive adaptations related to bilingual experiences. This study examined their behavioral manifestations in bilingual young adults by manipulating the cognitive load of a working memory task; the possibility to manipulate the difficulty of a cognitive task is necessary to observe behavioral outcomes associated with CE and automaticity. To this end, participants completed an n-back task ranging in difficulty from 0-back to 3-back, with the 3-back condition being commonly recognized as being a highly cognitively demanding one. We aimed to determine whether degree of bilingual experience could predict performance outcomes – accuracy, reaction times, and the speed/accuracy tradeoff – reflecting bilingualism’s putative dynamic impact on CE and automaticity in working memory. The results showed a positive relationship between degree of bilingual experience and working memory performance, particularly when the task-induced cognitive load increased. More experienced bilinguals demonstrated a smaller decline in performance when task difficulty intensified, a behavioral manifestation compatible with increased CE. Additionally, a relationship with expertise-dependent automaticity emerged, with the speed/accuracy tradeoff trajectory unfolding differentially across varying task difficulties at different degrees of bilingual experience.

Keywords: bilinguals, Cognitive efficiency, working memory