Abstract/Summary

It has been suggested that bilingualism is beneficial for executive control and could have positive long-term effects by delaying the onset of symptoms of degenerative diseases. This research investigates, for the first time, the impact of bilingualism on executive control (monitoring and inhibitory control) in individuals with Multiple Sclerosis (MS), a neurodegenerative disease which commonly causes deficiencies in the cognitive system. Bilingual and monolingual adults, with and without an MS diagnosis, performed a flanker task with two degrees of monitoring demands (high monitoring vs. low monitoring). Results showed that bilingual MS patients had inhibitory control and monitoring abilities that were similar to healthy bilingual controls. In contrast, monolingual MS patients showed similar inhibitory control but significantly worse monitoring abilities compared to monolingual healthy controls. We propose that the similar behaviour between bilingual groups suggests that bilingualism might counteract cognitive deficits related to MS, especially with respect to monitoring. The high monitoring cost observed in monolingual patients seems related to underlying deficits in monitoring and possibly switching, executive control abilities commonly impaired in MS patients from early stages. Our findings provide some preliminary evidence for the cognitive reserve hypothesis in bilingual MS patients.