Neuroprotective Effects of Long-term TaVNS in Early Parkinson's Disease Patients

This study is testing whether a gentle, non-invasive technique called transcutaneous auricular vagus nerve stimulation (taVNS) — which delivers mild electrical pulses through the outer ear to stimulate the vagus nerve — can slow the progression of early Parkinson's disease when combined with standard medication. **You may be eligible if...** - You are between 55 and 75 years old - You have been clinically diagnosed with Parkinson's disease within the past 3 years - Your Parkinson's is in an early stage (Hoehn and Yahr stage 2.5 or lower) - You are currently on standard Parkinson's medication **You may NOT be eligible if...** - You have significant memory or thinking problems (low score on a cognitive screening test) - You have taken certain neuroprotective medications (like rasagiline, selegiline, or GLP-1 drugs) within the past 90 days - You have taken medications that interfere with dopamine (antipsychotics, some anti-nausea drugs) in the past 90 days - You have previously received vagus nerve stimulation treatment - You have MRI contraindications (like some implants or severe claustrophobia) or significant brain abnormalities on imaging Talk to your doctor to see if this trial is right for you.