The goal of this clinical trial is to investigate the therapeutic efficacy of tTIS in patients with Parkinson's disease and to evaluate the immediate effects and conduct intrapatient comparisons of individualized 130 Hz Subthalamic Nucleus-transcranial Temporal Interference Stimulation (STN-tTIS) and Globus Pallidus Internus-transcranial Temporal Interference Stimulation (GPi-tTIS) on motor symptoms in patients with early to mid-stage Parkinson's Disease (PD) during "off" medication states.

The main questions this study aims to answer are:

1. Can tTIS significantly improve the motor symptoms of patients with Parkinson's disease?
2. Is the therapeutic effect of STN-tTIS superior to that of GPi-tTIS?

This clinical trial aims to verify the efficacy of tTIS in patients with Parkinson's disease and to explore which targets are better for improving PD motor symptoms.Patients were randomly assigned to receive Stimulation Type A, B, or C. Type A received STN-tTIS therapy; Type B received GPi-tTIS therapy; Type C received sham stimulation targeting the subthalamic nucleus.

Each session lasted 20 minutes, and patients were in the off-medication state for all treatments.The order of stimulation types was randomized, with at least 7 days of washout between sessions to avoid carryover effects. MDS-UPDRS-III evaluations were assessed before and after each treatment.

Inclusion Criteria:

• Diagnosis of primary Parkinson's disease (MDS);
• Hoehn & Yahr stage ≤ 3;
• Antiparkinsonian drugs must have remained unchanged in the past four weeks, and the dosage must have remained stable throughout the study.

Exclusion Criteria:

• Presence of neurological disorders that may affect the study (e.g., traumatic brain injury);
• Antipsychotics, antidepressants, or dopamine modulators outside of PD drugs;
• Metal devices in the head or heart (e.g., deep brain stimulators, pacemakers);
• Unstable vital signs.