Improving Stroke Rehabilitation with Vagus Nerve Stimulation
Stroke is a leading cause of neurological damage, with an estimated 795,000 cases reported in the United States each year. A large percentage of patients who suffer a stroke exhibit long-term impairments in motor function. Poststroke rehabilitation in part aims to promote adaptive changes in neural circuits to support recovery of function, but insufficient or maladaptive plasticity often limits benefits. Adjunctive strategies that support plasticity in conjunction with rehabilitation represent a potential means to improve recovery after stroke. Vagus nerve stimulation (VNS) has emerged as one such targeted plasticity strategy, providing phasic activation of neuromodulatory nuclei associated with plasticity. Repeatedly pairing brief bursts of VNS with motor training drives robust, specific plasticity in neural circuits. A number of studies in animal models of stroke and neurological injury demonstrate that VNS paired with rehabilitative training improves recovery of motor function. Moreover, emerging evidence from clinical trials indicates that VNS delivered during rehabilitation promotes functional recovery in stroke patients. Here, we provide a discussion of the existing literature of VNS-based targeted plasticity therapies in the context of stroke and outline challenges for clinical implementation.
KeywordsVagus nerve stimulation Vagal nerve stimulation Rehabilitation Stroke Neuroplasticity
Brain-derived neurotrophic factor
Disability-adjusted life years
Traumatic brain injury
Vagus nerve stimulation
We would like to thank Dr. Michael Kilgard and Dr. Robert Rennaker for insightful comments and discussion about the manuscript. This work was supported by grants from the NIH National Institute for Neurological Disorders and Stroke (R01 NS094384 and R01 NS085167) and by the Defense Advanced Research Projects Agency (DARPA) Biological Technologies Office (BTO) ElectRx program under the auspices of Dr. Doug Weber through the Space and Naval Warfare Systems Center, Pacific Cooperative Agreement No. HR0011-15-2-0017.
Conflict of Interest Statement
The author has no conflicts of interest to declare.
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