Endocannabinoids in Reward

This study will examine sex differences in the effects of cannabis in people that regularly use it. Men and women that use cannabis at least 4 days a week will participate in a study involving 3 in-person visits. The first visit will be used to determine eligibility for the study. The other two visits will last 7 hours each and take place at least two days apart. Visits include administration of either THC, the chemical responsible for many of the psychoactive effects of cannabis, or a placebo; completion of questionnaires; and a 1-hour brain scan. One visit will also include a blood draw for genetic testing.

Inclusion Criteria: 1. Able and willing to provide informed consent 2. Age 21-45 3. Meet DSM-5 criteria for CUD 4. Report cannabis use ≥4 days/week on average in the last 30 days at screening 5. Provide a THC-positive urine sample at screening 6. BMI between 18-30 kg/m2 7. Regular menstrual cycle (females only) 8. Willing to use non-hormonal birth control for the duration of study participation (females only) Exclusion Criteria: 1. Meet DSM-5 criteria for any lifetime psychotic or bipolar disorder 2. Urinalysis results indicative of recent drug use other than cannabis 3. Current use of any psychotropic medication or over-the-counter supplements deemed by the investigator to have the potential to interfere with study outcomes 4. Current treatment-seeking for CUD or other SUDs 5. Meet DSM-5 criteria for any current psychiatric disorder other than nicotine or caffeine use disorder, mild alcohol use disorder, CUD, or ADHD 6. Females who are pregnant, nursing, or planning to become pregnant 7. MRI contraindications (e.g., metallic implants, claustrophobia) 8. Significant history of nausea associated with the use of cannabis and/or THC 9. History of cardiac or seizure disorders 10. Allergy to sesame oil