Differentiating tics from functional (psychogenic) movements with electrophysiological tools

OBJECTIVE: We report on two patients that presented to our clinic with the differential diagnosis of functional movement disorder vs tic disorder. CASE REPORTS: The first patient is a 23-year-old woman with a 3-year history of repetitive involuntary neck flexion movements. The second patient is a 59-year-old man with a 10-month history of involuntary trunk jerks. In both cases, the polyelectromyographic study and the observation of Bereitschaftspotential helped us in making the final diagnosis. SIGNIFICANCE: The use of electrophysiological tools can be helpful in making the distinction between functional movement disorders and tic disorders.