taVNS for Upper Limb Rehabilitation

Early Phase 1

Completed

Interventions: Device: Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) + Task Specifc Training

Brief Summary: This study explores the use of a new form of neuromodulation known as transcutaneous auricular vagus nerve stimulation (taVNS) which stimulates the ear. This stimulation will be delivered concurrently with upper limb motor rehabilitation training (3 days/week for 4 weeks) in chronic stroke patients. Patients will undergo a series of baseline assessments (including a brain scan), a 4-week course of motor rehabilitation, and post-assessments (including a second brain scan)

Detailed Description: This study aims to refine and develop closed loop taVNS, establish activity with key biomarkers, and show initial feasibility in a small clinical trial. For paired taVNS to succeed as a clinical treatment, it is critical to develop and refine a closed-loop taVNS platform that delivers stimulation concurrently during specific movements of the motor rehabilitation training.

Aim 1 develops this novel motion-gated closed-loop system that delivers taVNS in synchrony with specific upper limb motor activation (n=5) Aim 2 will combine the development of the closed-loop system with the investigator's mechanistic understanding to explore an open-label pilot trial (n=20) using closed-loop taVNS paired with task-specific training to determine the feasibility, safety, and potential effect size of this novel combination therapy.

Recruitment & Eligibility

Inclusion Criteria

18-80 years old
Ischemic or hemorrhagic stroke that occurred at least 6 months prior
Completed conventional rehabilitation therapy at least one month prior
Unilateral limb weakness with Fugl Meyer-Upper Extremity Scale score less than or equal to 58 (out of 66)

Exclusion Criteria

Primary intracerebral hematoma, or subarachnoid hemorrhage
Bilateral upper extremity weakness
Other concomitant neurological disorders affecting upper extremity motor function
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 despite treatment, specifically SBP (Systolic Blood Pressure) / DBP (Diastolic Blood Pressure) >=180/100mmHg at baseline
Contraindicated for MRI scanning.

Arm && Interventions

Group	Intervention	Description
"unpaired" taVNS + Task Specific Training	Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) + Task Specifc Training	-
"paired" taVNS + Task Specific Training	Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) + Task Specifc Training	-

Primary Outcome Measures

Name	Time	Method
Change in Fugl-Meyer Assessment of the Upper Extremity	Mean change in FMA-UE score after 4 weeks of rehab, compared to baseline	The Fugl-Meyer Assessment of the Upper Extremity (FMA-UE) is a stroke rehabilitation assessment of arm/hand movement impairment. It is scored by assigning 30 items assessing voluntary arm/hand movements and 3 items assessing reflexes an ordinal rating (0=unable, 1=partial, 2=near normal), then summing the ratings to obtain a general statement of ability. Possible aggregate scores range from 0/66 to 66/66 points. Higher scores indicate greater levels of arm movement ability.

Secondary Outcome Measures