Embargo
Item embargoed until 2099-12-31Document type
ArticlePublication date
All rights reserved
Please use this identifier to cite or link to this item: https://hdl.handle.net/2445/66067
Overactivation of the Supplementary Motor Area in Chronic Stroke Patients
Journal Title
Director/Tutor
Journal ISSN
Volume Title
Related resource
Abstract
Stroke induces a loss of neural function, but it triggers a complex amount of mechanisms to compensate the associated functional impairment. The present study aims to increase our understanding on the functional reshape of the motor system observed in chronic stroke patients during the preparation and the execution of movements. A cohort of fourteen chronic stroke patients with a mild-to-moderate hemiparesis and fourteen matched healthy controls were included in this study. Participants were asked to perform a bimanual reaction time task synchronizing alternated responses to the presentation of a visual cue. We used Laplacian-transformed EEG activity (LT-EEG) recorded at the locations Cz and C3/C4 to study the response-locked components associated to the motor system activity during the performance of this task. Behaviorally, patients showed larger variable errors in synchronizing the frequency of execution of responses to the ISI and slower responses compared to controls. LT-EEG analysis showed that while control participants increased their SMA activity during the preparation of all responses, patients only showed this activity during their first response of the sequence. More interestingly, patients showed a clear increment of the LT-EEG activity associated to SMA short after responses compared to control participants. Finally, patients showed a hand-dependent inhibitory activity over motor areas ipsilateral to the response hand. Overall, our findings reveal drastic differences in the temporal dynamics of the LT-EEG components associated to the activity over motor and premotor cortices in chronic stroke patients compared to matched control participants during alternated hand responses.
Subject (English)
Citation
Citation
AMENGUAL, Julià L., et al. Overactivation of the Supplementary Motor Area in Chronic Stroke Patients. Journal of Neurophysiology. 2014. Vol. 112, num. 9, pags. 2251-2263. ISSN 0022-3077. [consulted: 17 of June of 2026]. Available at: https://hdl.handle.net/2445/66067