Cognitive Training Program for Children's OCD

Inclusion Criteria: * Ages between 8 and 12 years; * Clinically significant OCD as the principal problem. This is defined as follows: they must meet DSM-V criteria for OCD as assessed with the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children Present and Lifetime Version (K-SADS-PL). OCD must be the primary source of interference and distress (based on clinical evaluation with K- SADS-PL and Children's Yale-Brown Obsessive Compulsive Scale (C-YBOCS) and they must have clinically significant symptoms (i.e., C-YBOCS) ≥ 16; * Not on psychotropic medication (either treatment-naïve or free of psychotropic medication for at least three months) and not receiving current psychotherapy for OCD; * Ability to tolerate a treatment-free period (i.e., no treatment other than study CBT); * Capacity to provide informed assent Exclusion Criteria: * Current or past diagnosis of major depressive disorder, PTSD, substance/alcohol abuse, psychotic disorder, bipolar disorder, eating disorder, pervasive developmental disorder, substance/alcohol dependence, or any other Axis I disorder not listed above; * Active suicidal ideation; * Females who are pregnant or nursing; * Any major medical or neurological problem (e.g., unstable hypertension, seizure disorder, head trauma); -Positive urine screen for illicit drugs; * Presence of metallic device or dental braces; * IQ \<80;