Effects of Virtual Reality Intervention on Neural Plasticity in Stroke Rehabilitation: A Systematic Review

To systematically review and examine the current literature regarding the effects of virtual reality (VR)-based rehabilitation on neural plasticity changes in survivors of stroke.We searched 6 bioscience and engineering databases, including Medline via EBSCO, Embase, PsycINFO, IEEE Explore, Cumulative Index of Nursing and Allied Health, and Scopus.We selected studies reporting on the pre-post assessment of a VR intervention with neural plasticity measures published between 2000 and 2021.Two independent reviewers conducted study selection, data extraction, and quality assessment. They assessed methodological quality of controlled trials using the Physiotherapy Evidence Database scale and evaluated risk of bias of pre-post intervention and case studies using the National Institutes of Health Quality Assessment Tool.We included 27 studies (n=232). We rated 7 randomized-controlled trials as good quality and 2 clinical-controlled trials as moderate. Based on the risk of bias assessment, we graded 1 pre-post study and 1 case study as good quality, 1 pre-post study and 1 case study as poor, and the other 14 studies as fair. After the VR intervention, main neurophysiological findings across studies include: (1) improved interhemispheric balance; (2) enhanced cortical connectivity; (3) increased cortical mapping of the affected limb muscles; (4) the improved neural plasticity measures were correlated to the enhanced behavior outcomes; (5) increased activation of regions in frontal cortex; and (6) the mirror neuron system may be involved.VR-induced changes in neural plasticity for survivors of stroke. Positive correlations between the neural plasticity changes and functional recovery elucidates the mechanisms of VR-based therapeutic effects in stroke rehabilitation. This review prompts systematic understanding of the neurophysiological mechanisms of VR-based stroke rehabilitation and summarizes the emerging evidence for ongoing innovation of VR systems and application in stroke rehabilitation.