EFFECTS OF VIRTUAL REALITY INTERVENTION ON NEURAL PLASTICITY IN STROKE REHABILITATION: A SYSTEMATIC REVIEW

J. Hao¹, H. Xie¹, K. Harp², Z. Chen³, K.-C. Siu¹

Background: Virtual reality (VR) has been increasingly adopted in medicine for recent decades, and this emerging technology has shown promising results in stroke rehabilitation. As a computer-generated simulation technology, VR creates an enriched and gamified environment, facilitate task-specific training and provides multimodal feedback to augment the functional recovery by driving the experience-dependent neural plasticity. Currently, a majority of research focuses on effects of VR on functional recovery and clinical outcomes; understanding how the neural underpinnings of those effects are critical for optimizing the use of VR technology for patient care.

Purpose: This systematic review summarized the current literature regarding the effects of VR-based rehabilitation on neural changes in stroke patients.

Methods: By following the PRISMA reporting guideline, this systematic review was conducted and registered at the PROSPERO (ID: CRD42020196405). Six literature databases were searched, including Medline via Ebsco, Embase, PsycoINFO, IEEE Explore, Cumulative Index of Nursing and Allied Health, and Scopus. The results were limited to articles published between 2000-2020 and in English. The search strategy was designed by an experienced academic medical librarian and using keywords such as “virtual reality”, “stroke” and “neural plasticity”. The Physiotherapy Evidence Database (PEDro) scale was used to evaluate the methodological quality of all included randomized controlled studies. Two reviewers screened, selected and evaluated the articles independently, and any discrepancy was resolved by the third experienced reviewer.

Results: A total of 217 records were identified from the six databases, and another 4 were found from through other sources. After removing duplicates, 137 records remained and were screened. 29 full-text articles were assessed for eligibility, and finally 6 randomized controlled trials were included in this systematic review. In terms of the quality assessment, all of the 6 RCTs had the PEDro score no less than 6, which was considered as high quality. The interactive VR gaming systems were used in both upper and lower extremity exercises. The functional magnetic resonance, electroencephalogram (EEG) and navigated brain stimulation techniques were used to measure the changes of neural activities. The general findings regarding the VR-induced neural plasticity shown across the studies include: (1) improved interhemispheric balance, with the shift of activation from the contralesional to the ipsilesional primary sensorimotor cortex dominance during the paretic limb movement; (2) increased cortical representation mapping of the lesioned side muscles; (3) the correlation between improved neural plasticity measures and enhanced behavior outcomes; (4) increased activation of the frontal region identified by the EEG; (5) the mirror neuron system may be involved in the VR intervention.

Conclusion(s): Virtual reality induced changes in neural plasticity for stroke patients, these changes reflected the neural substrates of restoration and compensation of functional deficits. The positive correlation between the neural plasticity changes and functional recovery elucidates the mechanisms of VR’s therapeutic effects in stroke rehabilitation.

Implications: This review prompts the systematic understanding of the neurophysiological mechanisms of VR-based stroke rehabilitation, and provides the emerging evidence for ongoing innovation of VR system and its application in stroke rehabilitation.

Funding, acknowledgements: None.

Keywords: virtual reality, stroke, neural plasticity

Topic: Neurology: stroke

Did this work require ethics approval? No

Institution: University of Nebraska Medical Center

Committee: UNMC Institutional Review Board

Reason: This study was a literature review and didn't involve any human subjects.