Parkinson's disease tremor-related metabolic network: Characterization, progression, and treatment effects

►Parkinson's disease tremor network is characterized by covarying metabolic increases in the cerebellum, motor cortex, and putamen. ►This network correlates specifically with clinical tremor ratings, but not with other motor manifestations of the disease. Its activity is elevated in tremor-dominant versus akinesia-dominant patients. ►The activity of this network progresses over time at a slower rate than the previously validated akinesia network. ►Relief of tremor symptoms by thalamic DBS selectively reduces the activity of this network. By contrast, STN DBS reduces abnormal activity of both tremor- and akinesia-related brain networks.