Spinocerebellar ataxia (SCA) is a hereditary disorder with movement incoordination. The ataxia performed low intra-cortical facilitation mainly due to the degenerative cerebellum. Noninvasive sensory stimulations such as peripheral electrical stimulation were reported to modulate the excitability of the motor excitability. Neuromuscular electrical stimulation (NMES) was proposed as a neuromodulation tool for the aberrant motor excitability on the SCA. This study aims to investigate the effect of NMES on the motor excitability in the SCA, and the differentiation on the central or peripheral motor excitability changed by the NMES.

Inclusion Criteria:

• Clinical diagnosis of Spinocerebellar ataxia
• No history of epilepsy
• No other neuromuscular disorder
• No fracture within the last six months and restricted movement on the upper extremity
• Limited trembling hand allowed for the EMG recording.