Resting state fMRI reveals increased subthalamic nucleus-motor cortex connectivity in Parkinson's disease

► STN-motor cortex BOLD-FC is increased in PD. ► Results are a likely correlate of increased STN-M1 β-coherence observed in PD. ► Rigor and tremor appear to be associated with changes in STN-M1 hand area FC. ► Results agree with postulated overactivity in a “hyperdirect” M1-STN pathway.