Saeideh Ghafouri - English Department, Yazd University, Yazd, Iran
Mohammad Javad Rezai - English Department, Yazd University, Yazd, Iran.

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, ۲۰۰۰) in order to coordinate thoughts and actions (Koechlin, Ody, & Kouneiher, ۲۰۰۳). 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 ۹۷ participants aged ۱۸ to ۴۰ years. A group of ۶۳ Iranian monolinguals and ۳۴ 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.

Bilingual advantage, Late Bilingualism, Unbalanced Bilingualism, Cognitive Control, Stroop Task