The role of executive control in bilingual language production: A study with Parkinson's disease individuals

We approach these issues in two ways. First, we employed a language switching task to investigate the integrity of LC in a group of Catalan-Spanish bilingual individuals with PD, as compared to a group of matched healthy controls. Second, to test the relationship between domain-general EC and LC we compared the performances of individuals with PD and healthy controls also in a non-linguistic switching task. We highlight that, compared to controls, individuals with PD report decreased processing speed, less accuracy and larger switching costs in terms of RT and errors in the language switching task, whereas in the non-linguistic switching task PD patients showed only increased switching cost in terms of errors. However, we report a positive correlation between the magnitudes of linguistic and non-linguistic mixing costs in individuals with PD. Taken together, these results support the notion of a critical role of the basal ganglia and connected structures in LC, and suggest a possible link between LC and domain-general EC.