Overview
- An international team analyzed brain imaging from 863 people across U.S. and China cohorts, comparing Parkinson’s patients with healthy volunteers and individuals with other movement disorders.
- Parkinson’s was marked by excessive connectivity between the motor-cortex SCAN and deep-brain regions, with higher connectivity tracking with worse clinical symptoms.
- Standard therapies such as levodopa and brain stimulation reduced SCAN connectivity, and larger reductions were associated with greater motor improvement.
- In a randomized trial, SCAN-targeted transcranial magnetic stimulation produced a 56% response after two weeks versus 22% for stimulation at adjacent areas, based on 18 patients per group.
- The findings reframe Parkinson’s as a brain-network disorder and spur plans for larger trials and new noninvasive precision devices, while the causal link to substantia nigra neuron loss remains unresolved.