The role of the cognitive control system in recovery from bilingual aphasia: a multiple single-case fMRI study
Radman, NargesNeurology Unit, Department of Medicine, Faculty of Sciences, University of Fribourg, Switzerland
Mouthon, MichaëlNeurology Unit, Department of Medicine, Faculty of Sciences, University of Fribourg, Switzerland
Pietro, Marie DiNeurorehabilitation Department, University Hospital, University of Geneva, Geneva, Switzerland
Gaytanidis, ChrisovalandouNeurorehabilitation Department, University Hospital, University of Geneva, Geneva, Switzerland - Neuropsychology Unit, Fribourg Cantonal Hospital, Fribourg, Switzerland
Leemann, BeatriceNeurorehabilitation Department, University Hospital, University of Geneva, Geneva, Switzerland
Abutalebi, JubinCenter for Neurolinguistics and Psycholinguistics, San Raffaele University and Scientific Institute San Raffaele, Milan, Italy
Annoni, Jean-MarieNeurology Unit, Department of Medicine, Faculty of Sciences, University of Fribourg, Switzerland
English
Aphasia in bilingual patients is a therapeutic challenge since both languages can be impacted by the same lesion. Language control has been suggested to play an important role in the recovery of first (L1) and second (L2) language in bilingual aphasia following stroke. To test this hypothesis, we collected behavioral measures of language production (general aphasia evaluation and picture naming) in each language and language control (linguistic and nonlinguistic switching tasks), as well as fMRI during a naming task at one and four months following stroke in five bilingual patients suffering from poststroke aphasia. We further applied dynamic causal modelling (DCM) analyses to the connections between language and control brain areas. Three patients showed parallel recovery in language production, one patient improved in L1, and one improved in L2 only. Language-control functions improved in two patients. Consistent with the dynamic view of language recovery, DCM analyses showed a higher connectedness between language and control areas in the language with the better recovery. Moreover, similar degrees of connectedness between language and control areas were found in the patients who recovered in both languages. Our data suggest that engagement of the interconnected language-control network is crucial in the recovery of languages.