Language Switching Costs in Working Memory Tasks among Urdu–English Bilinguals: The Roles of Executive Function Capacity and Language Dominance

Abstract

Language switching is a defining feature of bilingual communication and provides important insights into the cognitive mechanisms underlying bilingual language control. This study investigates language switching costs during working memory tasks among proficient Urdu–English bilinguals, with particular attention to the moderating roles of executive function capacity and language dominance. Guided by theories of bilingual cognitive control and executive functioning, the study examined whether balanced and Urdu-dominant bilinguals differ in their ability to switch efficiently between languages while performing cognitively demanding tasks. Sixty proficient Urdu–English bilinguals participated in the study, including 30 balanced bilinguals and 30 Urdu-dominant bilinguals. Participants completed a language-switching paradigm involving digit span and n-back working memory tasks presented in both Urdu and English under alternating and non-alternating block conditions. Switching costs were calculated as differences in reaction time and response accuracy between switch and non-switch trials. Quantitative analyses revealed significant switching costs in both language directions, with greater costs observed for Urdu-to-English switches (mean reaction time cost = 78 ms) than English-to-Urdu switches (54 ms), demonstrating asymmetric switching effects that favored the dominant language. Balanced bilinguals exhibited significantly smaller switching costs than Urdu-dominant bilinguals (d = 0.62), indicating greater efficiency in language control and cognitive flexibility. Furthermore, working memory capacity, measured through the backward digit span task, showed a significant negative correlation with switching cost magnitude (r = –.49), suggesting that individuals with stronger executive function experienced lower cognitive costs during language switching. Accuracy analyses supported these findings, indicating fewer performance declines among balanced bilinguals across switching conditions. The results provide empirical support for the bilingual advantage hypothesis by demonstrating that balanced bilingualism and stronger executive functioning facilitate more efficient language control during demanding cognitive tasks. The study contributes to research on bilingual cognitive processing by extending evidence to the underexplored population of Urdu–English bilinguals and offers valuable implications for psycholinguistic models of bilingual language control, working memory, and executive function.