Analysis of Motor Module Transition from Tremor to Voluntary Reaching Movement in Patients with Parkinson's Disease**This research was supported in part by grants from the National Natural Science Foundation of China (No. 61361160415 and No. 81271684).

Voluntary movement could be initiated in spite of involuntary resting tremor in patients with Parkinson's disease (PD). It is unknown how the central nervous system (CNS) transits from the ongoing involuntary motor program of tremor to the execution of voluntary reaching movement. In this paper, muscle synergy analysis was used to unveil the motor module transitions from resting tremor to compound...