fMRI-guided Transcranial Magnetic Stimulation Treatment for Parkinson's Disease

Parkinson's disease (PD) is a neurodegenerative disorder commonly affecting middle-aged and elderly individuals. Besides conventional treatments such as medication (e.g., levodopa) and surgery (e.g., deep brain stimulation), non-invasive neuromodulation techniques, such as transcranial magnetic stimulation (TMS), have been widely used as a safe and well-tolerated non-pharmacological adjunct therapy for PD patients. However, the limited efficacy of TMS may be attributed to an incomplete understanding of PD-related cortical circuits and imprecise targeting.

Historically, the primary motor cortex (M1) has been selected as the repetitive TMS (rTMS) target for PD treatment. In 2022, Gordon et al. discovered a new network within the M1 that differs from effector-specific networks responsible for executing movements of specific body parts, such as those for the foot, hand, and face. This newly identified network, named the somato-cognitive action network (SCAN), is located in inter-effector regions and is responsible for motor planning, control, and coordination. Damage to this network correlates with key PD symptoms, making SCAN a promising new target for PD intervention.

This study aims to compare the efficacy of targeting the newly discovered SCAN versus traditional effector-specific networks in M1 using multimodal imaging and Intermittent theta burst stimulation (iTBS), a rapid form of rTMS. The objective is to provide new clinical evidence for non-invasive neuromodulation in Parkinson's disease.

Inclusion criteria

• Diagnosis of primary PD per the MDS Clinical Diagnostic Criteria (2015) or the Chinese Parkinson's Disease Diagnostic Criteria (2016).
• Age 18-75.
• Stable use of anti-PD medication for at least two months prior to enrollment.
• Normal cognitive function (MMSE > 24).
• Understanding of the study and signing of informed consent.

Exclusion criteria

• Diagnosed with other neurological diseases, such as stroke, brain tumor, traumatic brain injury, motor neuron disease, Alzheimer's disease, multiple sclerosis, etc.
• Implanted medical devices incompatible with MRI, such as deep brain stimulators, pacemakers, cochlear implants, or vagus nerve stimulators.
• Conditions contraindicated for MRI, such as claustrophobia, tattoos, or magnetic metal implants.
• Personal or family history of epilepsy.
• Prior neuromodulation treatments (e.g., TMS, transcranial electrical stimulation, transcranial ultrasound stimulation) within the last three months.
• Other health abnormalities that the investigator deems unsuitable for study participation.