Association between lesion location and sensorimotor rhythms in stroke - a systematic review with narrative synthesis

BackgroundStroke causes alterations in the sensorimotor rhythms (SMRs) of the brain. However, little is known about the influence of lesion location on the SMRs. Understanding this relationship is relevant for the use of SMRs in assistive and rehabilitative therapies, such as Brain-Computer Interfaces (BCIs)..MethodsWe reviewed current evidence on the association between stroke lesion location and SMRs through systematically searching PubMed and Embase and generated a narrative synthesis of findings.ResultsWe included 12 articles reporting on 161 patients. In resting-state studies, cortical and pontine damage were related to an overall decrease in alpha (similar to 8-12 Hz) and increase in delta (& SIM;1-4 Hz) power. In movement paradigm studies, attenuated alpha and beta (similar to 15-25 Hz) event-related desynchronization (ERD) was shown in stroke patients during (attempted) paretic hand movement, compared to controls. Stronger reductions in alpha and beta ERD in the ipsilesional, compared to contralesional hemisphere, were observed for cortical lesions. Subcortical stroke was found to affect bilateral ERD and ERS, but results were highly variable.ConclusionsFindings suggest a link between stroke lesion location and SMR alterations, but heterogeneity across studies and limited lesion location descriptions precluded a meta-analysis.SignificanceFuture research would benefit from more uniformly defined outcome measures, homogeneous methodologies, and improved lesion location reporting.