Virtual reality-induced cortical reorganization and associated locomotor recovery in chronic stroke: an experimenter-blind randomized study.

BACKGROUND AND PURPOSE Virtual reality (VR) is a new promising computer-assisted technology to promote motor recovery in stroke patients. VR-induced neuroplasticity supporting locomotor recovery is not known. We investigated the effects of VR intervention on cortical reorganization and associated locomotor recovery in stroke patients. METHODS Ten chronic stroke patients were assigned randomly to either the control group or the VR group. VR was designed to provide interactive real-life practice environments in which practice parameters can be individualized to optimize motor relearning. Laterality index (LI) in the regions of interests (ROIs) and locomotor recovery were measured before and after VR using functional MRI (fMRI) and standardized locomotor tests, respectively. The t test and nonparametric test were performed to compare the mean differences at P<0.05. RESULTS There was a significant difference in the interval change in the LI score for the primary sensorimotor cortex (SMC) between the groups (P<0.05), indicating that VR practice produced a greater increase in LI for the control group. However, the interval changes in the other ROIs were not significantly different (P>0.05). Motor function was significantly improved after VR (P<0.05). CONCLUSIONS Our novel findings suggest that VR could induce cortical reorganization from aberrant ipsilateral to contralateral SMC activation. This enhanced cortical reorganization might play an important role in recovery of locomotor function in patients with chronic stroke. This is the first fMRI study in the literature that provides evidence for neuroplasticity and associated locomotor recovery after VR.