Stuttering induced by thalamic deep brain stimulation for dystonia.

We report a patient in whom deep brain stimulation of the ventral intermediate nucleus of the thalamus (Vim) for treating dystonia reversibly induced stuttering at suboptimal stimulation parameters. Adjustments of stimulation parameters resulted in excellent control of dystonic motor symptoms and complete resolution of speech dysfluency. This is the first report on stuttering as an adverse effect of Vim stimulation which is primarily used to treat tremors of various etiologies.