Early evidence suggests the benefits of post-stroke motor rehabilitation may be enhanced by applying electrical stimulation to the ear. This study aims to test the new approach of pairing ear stimulation with motor rehabilitation in the home setting in stroke survivors with upper limb motor function deficits.

This study seeks to advance prior research conducted here at MUSC exploring the use of transcutaneous auricular vagus nerve stimulation (taVNS) paired with motor rehabilitation to improve motor function post-stroke. Early evidence from a recently completed NIH-funded, clinical trial suggests that our new approach of delivering electrical stimulation to the ear at the same time as motor rehabilitation double the clinical benefits of motor rehabilitation. These benefits are due in part to a facilitation of neuroplasticity caused by activating the auricular branch of the vagus nerve.

This project takes this approach one step further, moving it into the home in combination with telerehabilitation in order to make this technology more accessible to individuals in rural and remote areas. In order to accomplish this, investigators will a) conduct lab-based testing and validation of the stimulation triggering sensors for at-home use, and b) determine the safety, feasibility, and acceptability of at-home taVNS in five stroke survivors with unilateral upper limb motor deficits.

Investigators hypothesize that our lab-based validation will facilitate an optimized home intervention. Furthermore, investigators hypothesize taVNS will be safe and feasible to self-administer in the at-home setting. Lastly, investigation will help elucidate any challenges that may occur as investigators begin to expand this technology into future larger trials

Inclusion Criteria:

• 18-80 years old with an ischemic or hemorrhagic stroke that occurred ≥6 months prior;
• Ability to give consent;
• Unilateral limb (left or right) weakness with Fugl Meyer-Upper Extremity Scale score of 19-53/60 points which indicates adequate arm/hand use for rehabilitation tasks;
• active wrist flexion/extension ≥10° with active abduction/extension of thumb and at least 1 digit ≥10° to further assure ability to participate in rehabilitation tasks;
• Passive range of motion in affected shoulder, elbow and wrist within 20 degrees of normal values.

Exclusion Criteria:

• Other concomitant neurological disorders affecting upper extremity motor function;
• Presence of Dysphagia or aspiration difficulties;
• Prior injury to vagus nerve;
• Pregnancy;
• Documented history of dementia before or after stroke;
• Documented history of uncontrolled depression or psychiatric disorder either before or after stroke which could affect their ability to participate in the experiment;
• Uncontrolled hypertension;
• Botox injections within 4 weeks of the first day of rehabilitation therapy.