Post-task resting-state fMRI of walking-related neural activity in patients with stroke: immediate and delayed brain network dynamics

BACKGROUND: Walking impairments post-stroke are common but studying their neural basis with fMRI is difficult due to motion constraints. This study used post-task resting-state residual activity (PTRRA) to investigate walking-related neural activity without in-scanner movement. METHODS: Ten patients with subcortical ischemic stroke and ten matched healthy controls underwent two resting-state fMRI sessions: one immediately after overground walking, and another after a 20-minute delay. Clinical assessments included Fugl-Meyer Assessment and Timed Up-and-Go Test (TUGT). Analyses included ALFF, functional connectivity (FC), and graph theory. Enhanced FC was found between contralesional S1 and ipsilesional sensorimotor regions. ALFF changes and bilateral S1 FC were significantly associated with mobility outcomes. Graph theory results were atlas-dependent. CONCLUSION: Increased contralesional S1 activation and its enhanced connectivity with bilateral motor areas may reflect adaptive changes supporting post-stroke balance. The PTRRA method proved feasible for capturing post-walk neural activity and may be useful for assessing large-scale network dynamics after stroke.