No evidence for motor recovery-related cortical reorganization after stroke using resting-state fMRI

Branscheidt, M.; Ejaz, N.; Xu, J.; Widmer, M.; Harran, M. D.; Cortes, J. C.; Kitago, T.; Celnik, P.; Hernandez-Castillo, C.; Diedrichsen, J.; Luft, A.; Krakauer, J. W.

doi:10.1101/681320

bioRxiv · 10.1101/681320

No evidence for motor recovery-related cortical reorganization after stroke using resting-state fMRI

Branscheidt, M.·Ejaz, N.·Xu, J.·Widmer, M.·Harran, M. D.·Cortes, J. C.·Kitago, T.·Celnik, P.·Hernandez-Castillo, C.·Diedrichsen, J.·Luft, A.·Krakauer, J. W.

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Abstract

Cortical reorganization has been suggested as mechanism for recovery after stroke. It has been proposed that a form of cortical reorganization (changes in functional connectivity between brain areas) can be assessed with resting-state fMRI. Here we report the largest longitudinal data-set in terms of overall sessions in 19 patients with subcortical stroke and 11 controls. Patients were imaged up to 5 times over one year. We found no evidence for post-stroke cortical reorganization despite substantial behavioral recovery. These results could be construed as questioning the value of resting-state imaging. Here we argue instead that they are consistent with other emerging reasons to challenge the idea of motor recovery-related cortical reorganization post-stroke when conceived as changes in connectivity between cortical areas.

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Branscheidt, M., Ejaz, N., Xu, J., Widmer, M., Harran, M. D., Cortes, J. C., Kitago, T., Celnik, P., Hernandez-Castillo, C., Diedrichsen, J., Luft, A., Krakauer, J. W.. 2019-06-26. No evidence for motor recovery-related cortical reorganization after stroke using resting-state fMRI. https://doi.org/10.1101/681320

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