EXPRESS: Task-Specific Effects of Bilingualism on Proactive and Reactive Cognitive Control

The impact of bilingualism on the Dual Mechanisms of Control (DMC) is unclear, with studies reporting differing effects on proactive, reactive, or both control modes, likely influenced by task-specific demands. To examine whether bilingual-monolingual differences in DMC depend on task demands, we administered three cognitive tasks targeting distinct executive functions: the AX-Continuous Performance Task (AX-CPT), Sternberg, and Stroop tasks. Each task included proactive and reactive control versions and used Turkish verbal stimuli.Participants were 48 Turkish-Macedonian or Turkish-Albanian bilinguals (40 women, 8 men) and 50 Turkish monolinguals (41 women, 9 men). All participants completed all three tasks. Data from each task were analyzed separately using mixed designs, with group as a between-subjects factor and control type and trial type as within-subjects factors. Linear Mixed-Effects analyses assessed reaction times and accuracy.Results indicate that any relation between bilingualism and DMC may vary across task contexts. Bilingual participants showed some evidence of reduced proactive control in tasks involving semantic processing (AX-CPT and Sternberg), whereas reactive control seemed affected in the Stroop task, which requires suppression of linguistic meaning. However, these effects were modest, suggesting limited evidence for bilingual influences on DMC.