Prolonged silent periods produced by magnetic cortical stimulation in patients with cerebellar ataxia

Magnetic cortical stimulation can produce silent periods (SP) following excitatory motor responses. The SP in eight patients with cerebellar ataxia was examined. The onset latency of the SP in hand muscles after magnetic cortical stimulation was not different from that in control subjects. The duration of the SP was longer than that in control subjects, but the difference was not significant statistically. The end latency of the SP in patients with cerebellar ataxia was more prolonged than that in control subjects. Therefore, the inhibitory function may be enhanced in patients with cerebellar ataxia.