Testing a closely spaced brain stimulation programme

This clinical trial will evaluate the efficacy of accelerated Temporal Interference Stimulation (TIS) as a therapeutic intervention for individuals diagnosed with Parkinson's disease or secondary Parkinson's syndrome. Accelerated TIS will be delivered targeting the bilateral subthalamic nuclei of the brain. The primary objective is to assess whether accelerated TIS yields measurable improvements in motor performance and verbal speech function among enrolled subjects. Functional magnetic resonance imaging (fMRI) will be adopted as an auxiliary imaging modality to objectively characterize underlying cerebral functional alterations induced by accelerated TIS intervention. The core scientific research questions to be addressed in this trial are listed as follows: * Will accelerated TIS administered to the bilateral subthalamic nuclei produce significant improvements in motor function and speech performance among enrolled subjects with Parkinson-related disorders? * What quantitative and qualitative modifications in cerebral functional activity will be detected via fMRI after standardized accelerated TIS intervention administration? Investigators will implement a four-arm parallel controlled comparative design for all enrolled eligible subjects. All confirmed Parkinson's disease patients will undergo standardized random grouping and be allocated into two independent research arms. Subjects in the experimental arm will receive continuous, standardized accelerated TIS intervention targeting bilateral subthalamic nuclei. Subjects in the control arm will receive matched sham stimulation intervention. Sham stimulation adopts identical operation procedures, equipment wearing mode and on-site operating environment as formal accelerated TIS, with no valid neuromodulation therapeutic effect generated. Identical random grouping, intervention arrangement and controlled research design will be fully implemented in eligible subjects diagnosed with secondary Parkinson's syndrome. Rigorous controlled grouping design will ensure objective, verifiable data support for verifying the actual intervention efficacy of accelerated TIS on motor dysfunction and speech impairment in Parkinson-related patients. All enrolled subjects will complete the following standardized trial procedures in full compliance with the trial protocol: * Receive continuous targeted intervention of either formal accelerated TIS or matched sham stimulation on bilateral subthalamic nuclei, with consecutive 5-day fixed-course administration in strict accordance with trial operating specifications * Complete unified fMRI brain scanning examinations and standardized motor function as well as speech function quantitative evaluation assessments at two fixed time nodes, including the baseline time point before intervention initiation and the follow-up time point after all intervention courses are completed * Truthfully record all adverse reactions and abnormal physical discomfort symptoms that occur throughout the whole intervention and follow-up observation cycle in standardized adverse event registration forms