The Effects of Bilingualism on Attention and Task-Switching

Abstract Imaging studies have indicated that when bilingual people switch between languages, there is activation of brain areas known for executive function. This study aimed to clarify the effects of bilingualism on attention and task-switching capabilities by measuring event-related potentials, ERPs, during two tasks: subjects participated in an auditory Oddball paradigm, following the Oddball paradigm, subjects took the Madrid Card Sorting Test, MCST—a computerized version of the Wisconsin Card Sorting Test. Both tests measured P300 potentials, which are indicative of significant attentional shifts. These shifts in attention are imperative to task-switching abilities. Participants were 49 students, staff, and faculty from The College of Wooster; however, EEG data was analyzed for only 25 participants between the ages of 18 and 22 —12 monolingual and 13 bilingual. Results showed that there were no behavioral differences of accuracy or reaction time in the MCST. However, bilingual participants produced significantly smaller P3b potentials during this task, indicating that they required less activation to produce the same behavioral output. The Oddball paradigm showed significant novelty effects but no group differences. Therefore, bilingual and monolingual participants did not show significant differences in the purely attentional task, but they did in the task-switching paradigm. Because the attention pathway is primarily localized in the parietal lobe, and task-switching incorporates both parietal and prefrontal activities, these findings indicate that the main effects of bilingualism on taskswitching are likely due to changes in prefrontal activation. This evidence supports the hypothesis that bilingual people show significantly greater efficiency in task-switching abilities. Key Words: bilingualism, attention, task-switching, event-related potential