Whether bilingualism confers non-linguistic cognitive advantages continues to generate both interest and debate in the psychological sciences. In response to mixed reports and methodological critiques, researchers have embraced more rigorous practices when investigating bilingual effects, including those in the domain of cognitive control. Despite considerable advances, one significant issue persists: the assumption that task performance remains stable over time. To address this, the present study investigated the relationship between bilingual language experience and Simon task performance modeled as a continuous function of time. In a sample of Mandarin-English bilingual young adults, we identified distinct patterns of results across both conventional and time-sensitive performance trajectory measures with each supporting a different relationship between language experience and cognitive control. Results suggest that reliance on conventional performance measures may be partially responsible for mixed results, necessitating reevaluation of how bilingual effects on cognitive control manifest and which analysis methods best support their identification.

Effective communication in multilingual environments requires bilinguals to constantly monitor linguistic cues. It is hypothesized that the constant need to monitor may result in improved attention. However, previous investigations have reported mixed, often null results, with positive findings attributed to non-linguistic variables. To address these issues, we investigated whether higher levels of bilingualism were associated with improved attentional function in a sample of culturally and socioeconomically homogenous Mandarin–English speaking bilingual adolescents. Participants completed the Attention Network Task to assess attentional network function. Data were analyzed using linear mixed-effects models in order to account for nontrivial differences. Mixed results provide partial support for domain general cognitive benefits associated with higher levels of bilingualism. Both improved and reduced performance differed based on the specific dimension of bilingualism and the attentional network assessed. Findings support the conclusion that separable dimensions of bilingual language experience assert different influences on attentional network function.