Transcranial Direct Current Stimulation Augmented Exposure and Response Prevention for Obsessive-Compulsive Disorder

tDCS for Inhibitory Control Deficits: A Test in OCD

This study is investigating whether combining noninvasive brain stimulation with behavior therapy can help to improve outcomes for obsessive-compulsive disorder (OCD). Exposure and response prevention (ERP) -- a specific type of behavior therapy -- is a first line treatment for OCD. This study will test whether a form of noninvasive brain stimulation called transcranial direct current stimulation (tDCS), can help ERP work better.

Inclusion Criteria:

• Current primary OCD diagnosis and current Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) total score of ≥16
• 18-65 years of age
• Ability to speak, read, write, and understand English sufficiently well to complete study procedures and provide informed consent
• Right-handed
• No use of psychiatric medications or stable psychiatric medication use for a minimum of 6 week prior to study entry. Psychiatric medications will be limited to the following: serotonin reuptake inhibitors (SRI; including clomipramine), combination antidepressants (including bupropion and serotonin-norepinephrine reuptake inhibitors), buspirone, benzodiazepines, and/or stimulants
• Naive to tDCS

Exclusion Criteria:

• Active substance use disorder
• Lifetime diagnosis of psychotic or bipolar mood disorder
• Previous minimally adequate trial of ERP (e.g., at least 16 sessions including both therapist and self-directed exposure and response prevention)
• Therapy outside the study protocol which has evidence for efficacy with OCD during the study intervention period
• Active suicidal or homicidal ideation
• Organic brain disease or injury
• Any health problems that would interfere with study participation, including contraindications to tDCS (e.g., skin condition, mental implant in skull)
• Women who are pregnant or breastfeeding. All women participants of child-bearing age are required to have a negative pregnancy test prior to treatment, and must use medically acceptable birth control during study participation. Medically acceptable birth control includes: established oral, injected, implanted, or vaginal ring hormonal contraception, an intrauterine device (IUD), two barrier contraception methods (condom or occlusive cap with spermicidal foam/gel/film/cream/suppository), or having a vasectomized partner
• Use of anticonvulsant medications (including depakote, gabapentin, tegretol, dilantin, lamictal) and/or glutamate-acting agents (including n-acetylcysteine, riluzole, amantadine, memantine).