Impaired Motor Preparation in Writer's Cramp Patients: A fMRI Study at 3T

Purpose: Writer's cramp is a task-specific focal dystonia, characterized by involuntary muscle contractions. Clinical symptoms often manifest upon holding a pen, even before writing, and behavioral and electrophysiological studies suggest abnormal motor processing already during the phase prior to movement onset. Disturbed activity in premotor cortical and interconnected subcortical areas has been observed, but previous functional neuroimaging studies were not designed to distinguish between motor preparation and execution. Our aim was to separately characterize motor preparation and execution related brain acti…