Cranial Nerve Neuromodulation to Improve Arm Function and Brain Plasticity in Stroke

What this study is about

Following a stroke, persistent residual muscle weakness in the upper limb (UL) drastically impacts the individuals' quality of life and level of independence. Training interventions are recommended to promote UL motor recovery, and recent studies have shown that training must be tailored to each individual's recovery potential to maximise training gains. Complementary to training interventions, non-invasive brain stimulation devices (NIBS) can help support the provision of post-stroke care by modulating brain excitability and enhancing recovery. Among NIBS, cranial nerve non-invasive neuromodulation (CN-NINM) is gaining increasing attention in rehabilitation since it can directly and non-invasively stimulate the tongue's cranial nerves. The impulses generated can then reach the motor cortex, induce neuroplastic changes and support recovery. Promising results in various neurological populations have been observed, but in stroke, the efficacy of CN-NINM at improving arm motor recovery and brain plasticity is yet to be determined. This is what the present project intends to address, using a stratified randomized controlled trial, where participants in the chronic phase of a stroke will take part in a 4-week individualized training program of their affected UL in combination with real or sham CN-NINM. Before and after the intervention, participants will undergo clinical and neurophysiological evaluations to thoroughly evaluate CN-NINM-induced changes in UL motor function and associated neuroplastic changes. The proposed study will allow an in-depth evaluation of the effects of CN-NINM for an eventual implementation in clinics and at home to support optimal post-stroke recovery.

Who can join (things the study team will check)

✅ You may be able to join if…

• be ≥18 years of age;
• have had a unilateral supratentorial stroke;
• be in a chronic stage of recovery (>6 months);
• present some UL motor recovery (Fugl-Meyer Stroke Assessment [FMA-UE] score ≥25/66);
• are not involved in rehabilitation treatments.

🚫 You may not be able to join if…

• significant spasticity at UL (score >3 on the modified Ashworth scale);
• major sensory deficit at UL (a score <25/34 on the Nottingham sensory assessment and a score <6 on the vibration threshold assessment);
• hemineglect (> 70% of unshaded lines on the same side as the motor deficit on the Line Cancellation test);
• apraxia (score >2.5 on the Alexander test);
• a neurological disorder other than stroke-related;
• orthopedic problems at UL;
• cognitive impairment (score <2/5 on the Mini-Cog);
• significant pain intensity at UL (a score ≥ 6/10 on the Visual Analog Pain Scale);
• absence of MEP (peak-to-peak MEP amplitude <20μV);
• contraindications to CN-NINM and TMS.

Where this trial is running

• CRIR/Feil/Oberfeld Research Center; Centre intégré de santé et de services sociaux de Laval; Jewish Rehabilitation Hospital, Laval, Quebec, Canada
• CIRRIS, Québec, Quebec, Canada
• Centre de recherche sur le vieillissement, Sherbrooke, Quebec, Canada

Who to contact

Marie-Helene Milot, PhD · 819-780-2220 · marie-helene.milot@usherbrooke.ca

It's completely normal to call and ask questions before deciding anything. Mention the study ID: NCT06386510.