Reorganization of Motor Execution Networks During Sub-Acute Phase After Stroke.

Numerous studies focused on brain reorganization after stroke from aspects of task-related brain activity and resting-state brain networks. However, studies focusing on the longitudinal reorganization of task-state brain networks were scarce. In this study, functional magnetic resonance imaging data were collected from twelve stroke patients during blocked finger-tapping task at four post-stroke time points (less than 10 days, around 2 weeks, 1 month and 3 months), respectively. The dynamic changes and prognostic value of the network parameters (i.e., topological parameters, functional connectivity and nodal parameters) in task-state motor execution networks were thoroughly evaluated. We found that the topological configuration (clustering coefficient and characteristic path length) of task-state motor execution networks underwent significant shift during stroke recovery. Especially, we found the topological configuration of task-state motor execution networks at the early recovery stage were capable of predicting the motor function restoration during sub-acute phase. In addition, we found increasing functional connectivity between ipsilesional cerebellum and motor cortices in task-state motor execution networks. In general, this study demonstrated the reorganization and prognostic value of task-state brain network after stroke, which provides new insights into understanding the brain reorganization and rehabilitation after stroke.