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

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).