Exploring the Effect of Late, Unbalanced Bilingualism on Cognitive Control

One of the most fascinating and enduring mysteries of human cognition concerns the process of cognitive control, a function that depends on the engagement of the prefrontal cortex (Miller, 2000) in order to coordinate thoughts and actions (Koechlin, Ody, & Kouneiher, 2003). Considering language switching as a practice to improve the general control mechanisms, the effect of bilingual experience on cognitive control has been a matter of scientific debate in the past two decades. The existence of bilingual advantage, however, has remained highly controversial in the bilingualism literature because of a mix of negative, positive, and null effects. The current study investigated the influence of late unbalanced bilingualism on cognitive control among 97 participants aged 18 to 40 years. A group of 63 Iranian monolinguals and 34 Persian-English bilinguals took part in this study and were exposed to a computerized version of Stroop Color and Word Task so as to measure conflict monitoring and inhibition. An independent samples t-test analysis of the Stroop results showed no significant differences in the mean color-word interference effects (RT and score) across both groups. Therefore, late unbalanced bilinguals are not cognitively different from their monolingual counterparts. The study findings indicate that the role of other key variables such as intellectual, physical, and social activities should further be considered in dealing with the notion of bilingualism and cognitive control.