Transcranial Direct Current Stimulation of Dorsolateral Prefrontal Cortex in Patients with Obsessive Compulsive Disorder to Improve Decision Making and Reduce Obsession Symptoms

Objective: Recent studies on treating obsessive compulsive disorder (OCD) have investigated noninvasive brain stimulation techniques such as transcranial direct current stimulation (tDCS) to improve patients’ impaired emotion and cognition. However, such experiments have yielded mixed results, especially with respect to cognition. This study aimed to investigate whether anodal and cathodal tDCS applied over the dorsolateral prefrontal cortex (DLPFC) would improve decision making and reduce obsession symptoms in patients with OCD. Methods: the current study is analysis of variance. In this regard, 20 patients with obsessive compulsive disorder (n=20) were randomly assigned to receive either experimental (active) or control (sham) tDCS. To measure cognitive functions, the participants underwent a series of decision making neuropsychological tasks; to measure obsession symptoms, the Yale-brown obsessive compulsive and Beck anxiety scale (BAI) were used. The parameters of active tDCS included administration of 2 mA for 20 minutes per day for 15 consecutive days, anode electrode over the right DLPFC (F4), and cathode electrode over the left DLPFC (F3) region. Results: After 10 sessions of anodal and cathodal tDCS, patients showed significant improvement in decision making tasks. The same results were observed for obsession symptoms. Conclusion: The data were analyzed by SPSS 18.0.0 software, using analysis of variance methods.This study demonstrated that anodal tDCS over left DLPFC, concurrent with cathodal tDCS over right DLPFC, improved cognitive impairment and reduced obsession symptoms in patients with OCD.