Extended Effects of Cannabis Abstinence on Clinical Symptoms and Cognition in Depression

Inclusion Criteria: * All participants must be between the ages 18-55 * Meet SCID for DSM-5 diagnostic criteria for cannabis use disorder, moderate to severe * Meet SCID for DSM-5 diagnostic criteria for Major Depressive Disorder * Be an outpatient receiving a stable dose of antidepressant medication for at least three months (to ensure stability of depressive symptoms * Have a Hamilton Depression Rating Scale (HDRS-17) at baseline assessment in the range of 12-25.. * Have a Full-Scale IQ ≥ 80 as determined by the WTAR * Be a non-treatment seeking cannabis user * Evidence of sufficient motivation and effort as measured by a Test of Memory Malingering (TOMM) score ≥ 45. Exclusion Criteria: * Meets criteria for substance use disorder of alcohol or other illicit substances within the past 6 months (with the exception of cannabis, nicotine, or caffeine) * Positive urine screen for illicit substances other than cannabis, nicotine, or caffeine * Current suicidal or homicidal ideation * Psychotic disorder diagnosis (e.g. schizoaffective disorder, major depression with psychotic features) as determined by the SCID * Treatment seeking for cannabis use * Meet SCID for DSM-5 diagnostic criteria for Bipolar Disorder * Head Injury\> 5 minutes LOC * Exceed upper and lower cut-offs on HSRD-17 (See Inclusion Criteria)