Effects of Trans-Auricular Vagal Stimulation on Neuromotor Recovery in Subacute Stroke During Technological and Traditional Training

This randomized pilot clinical study aims to investigate the effects of trans-auricular vagus nerve stimulation (tVNS) on neuromotor recovery in patients in the subacute phase after stroke. Participants admitted for intensive rehabilitation at ICS Maugeri Centers (Montescano, Pavia, Nervi) will be randomized into four groups receiving either traditional or technological rehabilitation (Khymeia device), combined with active or sham tVNS. The Parasym® device (CE 0197) delivers non-invasive stimulation of the auricular branch of the vagus nerve at the left ear for 60 minutes daily. The primary outcome is the improvement in upper limb motor function, assessed by the Fugl-Meyer scale. Secondary outcomes include other clinical, cognitive, and psychological measures, as well as neurophysiological and cardiovascular autonomic parameters. The study hypothesizes that coupling tVNS with rehabilitation enhances cortical plasticity and accelerates motor recovery. Adverse effects are expected to be minimal, with previous studies reporting only mild transient skin irritation. The results may provide new insights into the neurophysiological mechanisms of recovery and support the integration of non-invasive neuromodulation in post-stroke rehabilitation.