Using a Brain-Computer Interface System for Rehabilitation of Upper Extremity Motor Function after Stroke: Neuroplastic and Practical Insights

Demographic shifts toward an aging population combined with increasing stroke survival rates have made stroke a leading cause of acquired disability. With many stroke patients failing to achieve full recovery using traditional therapies, this growing population of stroke survivors constitutes a considerable need for new options in stroke rehabilitation. One new class of therapies being developed to address this growing need incorporates neuromodulatory training using brain-computer interface (BCI) technology in an attempt to harness the latent recovery potential in these patients and facilitate functional gains. Given the brain-based nature of such interventions, understanding the brain and behavioral relationships associated with these therapies is key to understanding the recovering brain. The focus of this work is to examine the neuroplastic effects in stroke survivors using one such BCI device.;We recruited stroke patients with persistent upper extremity motor impairment and administered rehabilitative therapy using a BCI system with integrated functional electrical stimulation and tongue stimulation. Subjects were assessed with magnetic resonance imaging at various time points relative to BCI therapy to examine functional and structural brain changes. We also examined brain-behavior relationships that emerged during the therapy period and dose-response effects based on de facto variation in therapy administration parameters.;Our results demonstrated neuroplastic changes associated with BCI therapy in the form of shifts in brain activation laterality, which correlated with simultaneous behavioral changes. Changes in behavioral outcome measures were also shown to correlate with changes in functional connectivity in the motor network and with changes in measures of structural integrity in the corticospinal tract. The results showed both direct and indirect dose-response relationships with changes in brain and behavioral measures.;These analyses suggest that rehabilitative therapies using BCI systems may represent a means of eliciting additional improvements in stroke survivors through neuromodulatory training. The findings suggest a beneficial compensatory role for the contralesional hemisphere in stroke recovery using BCI therapy, particularly among more severely impaired individuals, and hint at the presence of differential responses to BCI-based rehabilitative therapy among various subpopulations of stroke survivors. Such insights may be used to inform the design of future BCI systems and studies.