Deep brain stimulation in movement and psychiatric disorders.

Deep brain stimulation (DBS) is the most focal and invasive of the electromagnetic brain stimulation therapies. A subcutaneous pulse generator provides continuous stimulation of circumscribed brain tissue via a multicontact microelectrode that terminates within its target. The result is an adjustable, reversible, and specific therapy. Despite limited understanding of its mechanisms of action, DBS efficacy has been established in several movement disorders, and promising reports have emerged for Tourette syndrome, obsessive-compulsive disorder, and major depression. Deep brain stimulation may prove to be a reasonable option for severely ill and treatment-resistant patients who otherwise have limited therapeutic options and a poor prognosis.