Overview
The goal of this clinical trial is to compare the effects of different modes and frequencies of transcutaneous auricular vagus nerve stimulation (taVNS) on non-motor symptoms in people with Parkinson's disease. The main questions it aims to answer are:
Which mode and frequency of taVNS is most effective in improving non-motor symptoms? Are there any side effects or safety concerns with different taVNS frequencies? Researchers will compare three types of taVNS: 25 Hz non-expiratory gated, 25 Hz expiratory gated, and 100 Hz expiratory gated stimulation.
Participants will:
Receive each type of taVNS in three 2-week cycles, with 2-month breaks between cycles Undergo neuropsychological assessments, imaging, eye-tracking, and biological sample collection before and after each cycle.
Description
This study employs a three-cycle crossover design to compare the effects of three different modes and frequencies of transcutaneous auricular vagus nerve stimulation (taVNS). The interventions include: 25 Hz non-expiratory gated taVNS, 25 Hz expiratory gated taVNS, and 100 Hz expiratory gated taVNS. Participants will be randomly assigned to one of three groups, with each group receiving a different intervention during each cycle, lasting 2 weeks per cycle. A 2-month washout period will be implemented between cycles to eliminate any carryover effects.The study design will include neuropsychological assessments, imaging, eye-tracking data collection, and biological specimen collection before and after each intervention.
Eligibility
Inclusion Criteria:
- Age: 40 years or older.
- Confirmed diagnosis of Parkinson's disease (PD) per the United Kingdom Brain Bank Criteria by a neurologist specialized in movement disorders.
- Participants must be on a stable dose of all medications for at least 2 weeks, with no planned adjustments to anti-PD medications for the next 3 months.
- In the second version of the Non-Motor Symptoms Scale (NMSS-2) for Parkinson's disease, a score of ≥1 is assigned to either question 4 or question 8.
- Participants must be in good mental health and capable of completing behavioral tests and transcutaneous auricular vagus nerve stimulation.
Exclusion Criteria:
- Mini-Mental State Examination (MMSE) score <24.
- History of head injury, stroke, or other neurological disorders.
- Includes implanted cardiac pacemakers post-DBS operation, local infections, ear loss, or metal implants at the stimulation site.
- Current use of nonsteroidal anti-inflammatory drugs (NSAIDs) or corticosteroids.
- Inability to complete follow-up assessments.