tDCS for Treatment Resistant Obsessive Compulsive Disorder

Inclusion Criteria: * Meets criteria for obsessive compulsive disorder according to Diagnostic and Statistical Manual (DSM IV) with a "good insight" (BABS) * No current depressive and suicidal risks * No epileptic pathology * Age: Participants will be both males and females, 18-70 years of age included. * Chronic Obsessive compulsive disorder ( Total Y-BOCS\>20 or Y-BOCS one subscale \> 15) * Obsessive compulsive disorder resistant to pharmacology treatment : 1. at least 2 antidepressants (IRS type) (\> 12 weeks) 2. cognitive and comportment therapy since at least one year * Treatment stability (antidepressants) for more than 12 weeks without significant improvement. * Affiliation to a social security system (recipient or assignee), * Signed written inform consent form Exclusion Criteria: * Female subject who is pregnant, or of child-bearing age, sexually active and not using reliable contraception or who is nursing, * Patient under curators * Patient hospitalized under duress * Meets another diagnosis of axe 1 of DSM-IV * Current depressive or suicidal risks * Patient with any form of metal in the cranium, a pacemaker, skull defects, or skin lesions to the scalp (cuts, abrasions, rash) * Epileptic patient * Patient with a medical history of cranial trauma * Patient unable to give his or hers informed consent