Deep brain stimulation for psychiatric disorders.

Over the last decade, deep brain stimulation (DBS) has revolutionized the practice of neurosurgery, particularly in the realm of movement disorders. It is no surprise that DBS is now being studied in the treatment of refractory psychiatric disease. Deep brain stimulation has inherent advantages over previous lesioning procedures. It is fully reversible, and stimulation can be adjusted according to a patient's changing symptoms and disease progression. Coupled with the fact that the stimulation can generally be turned on or off without the patient's awareness, DBS provides a unique opportunity for double-blinding studies. To undertake DBS for psychiatric conditions, appropriate surgical targets must be chosen. What is most strongly supported is the role of cortico-striato-thalamocortical (CSTC) loops in the pathophysiology of psychiatric symptoms. Recent functional imaging studies have consistently found evidence that corroborate this model of psychiatric symptom pathogenesis. Based on the psychiatric and cognitive effects seen in recent movement disorder surgery, it is apparent that modulation of neural systems subserving psychiatric phenomenon can be accomplished by DBS. The few published studies on DBS for obsessive-compulsive disorder (OCD) suggest that this can be done safely. While efficacy data are still uncertain, initial data are promising.