Polarity-dependent effects of transcranial direct current stimulation in obsessive-compulsive disorder.

Polarity-dependent effects of transcranial direct current stimulation in obsessive-compulsive disorder. Neurocase. 2015 May 14;:1-5 Authors: D'Urso G, Brunoni AR, Anastasia A, Micillo M, de Bartolomeis A, Mantovani A Abstract About one third of patients with obsessive-compulsive disorder (OCD) fail to experience significant clinical benefit from currently available treatments. Hyperactivity of the presupplementary motor area (pre-SMA) has been detected in OCD patients, but it is not clear whether it is the primary cause or a secondary compensatory mechanism in OCD pathophysiology. Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique with polarity-dependent effects on motor cortical excitability. A 33-year-old woman with treatment-resistant OCD received 20 daily consecutive 2 mA/20 min tDCS sessions with the active electrode placed on the pre-SMA, according to the 10-20 EEG system, and the reference electrode on the right deltoid. The first 10 sessions were anodal, while the last 10 were cathodal. Symptoms severity was assessed using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) severity score. In the end of anodal stimulation, OCD symptoms had worsened. Subsequent cathodal stimulation induced a dramatic clinical improvement, which led to an overall 30% reduction in baseline symptoms severity score on the Y-BOCS. Our study supports the hypothesis that pre-SMA hyperfunction might be respons...
Source: Neurocase - Category: Neurology Authors: Tags: Neurocase Source Type: research