Semantic interference in second language learners: Cognitive control and proficiency in an L1-dominant context

Aims and objectives/purpose/research question: This study explores how L2 learners in an L1 environment resolve semantic interference from interlexical homographs, examining links with general cognitive control, reactive/proactive cognitive control, and L2 proficiency. Methodology: A cross-sectional design was employed with 29 Spanish–English bilingual university students. Participants completed a Semantic Judgment Task to assess semantic interference, along with tasks measuring general cognitive control and control strategy preference. L2 proficiency was assessed using standardized tests. Data and analysis: Accuracy and reaction times in the Semantic Judgment Task served as dependent variables, with L2 proficiency, general cognitive control, and control mode preference (proactive vs reactive) as predictors. Mixed-effects models included random intercepts and slopes for participants and items to account for variability. Findings: Performance was strongly determined by condition, with interlexical homographs (C1) yielding the lowest accuracy and slowest RTs. Beyond this condition effect, higher L2 proficiency and better general control predicted greater accuracy. Proactive versus reactive tendencies also modulated accuracy, with more reactive individuals performing better overall, though Behavioral Index Shift did not significantly affect RTs. These findings suggest that both linguistic proficiency and individual differences in control strategies shape bilingual word recognition under semantic judgment. Originality: This study contributes novel evidence by focusing on L2 learners in an L1-dominant environment, a population underrepresented in bilingualism research, and by examining the interaction between cognitive control strategies and proficiency outside immersion contexts. Significance/implications: Findings suggest that academic exposure alone does not guarantee greater reliance on proactive control. Instead, reactive control may be more adaptive when resolving interlexical competition, with implications for pedagogical approaches that support L2 processing in academic settings.