Clinical Research Directory

Inclusion Criteria: * Individuals with high scores on obsessive-compulsive traits (with or without a diagnosis of OCD established by a psychiatrist) and healthy volunteers (male or female) between 18 and 70 years. Compulsive individuals without an OCD diagnosis are individuals without a history of psychiatric or other major medical conditions but scoring abnormally high on the Obsessive-Compulsive Inventory (OCI) questionnaire. Exclusion Criteria: * Current or previous neurological disease, severe somatic disease, or consumption of medical drugs likely to influence the test results * Non- fluent in Danish or pronounced visual or auditory impairments * Current or past learning disability. * Pregnancy * Lactation * Participation in experiments with radioactivity (\> 10 mSv) within the last year or significant occupational exposure to radioactivity. * Contraindications for MRI (pacemaker, metal implants, etc.). * Allergy to the ingredients in the administered drug. * Abnormal ECG (e.g. prolonged QT syndrome). * Dizzy when changing from supine to upright position (e.g. postural orthostatic tachycardia syndrome). * Mild hypotension (blood pressure below 100/70 mmHg) or hypertension (blood pressure above 140/90 mmHg). * Head injury or concussion resulting in loss of consciousness for more than 2 min. * Alcohol or drug abuse * Drug use other than tobacco and alcohol within the last 30 days. * Hash \> 50 x lifetime. * Drugs \> 10 x lifetime (for each substance). * Current medication with serotonergic acting compounds. Use of other psychoactive substances must be stable at least one month prior to inclusion and maintained throughout the study. * Severe physical impairments affecting eyesight or motor performance. * For the OCD group: other Axis I mental disorder as primary diagnosis according to ICD-10 criteria. * For healthy volunteers: any current or former primary psychiatric disorder (Axis I WHO ICD-10 diagnostic classification).