Inclusion Criteria:

• * 18-55 years old
• * Right handed
• * CNB use within past 2 years and felt "high" when used
• * Able to read, speak, and understand English
• * Able and willing to provide written informed consent, and willing to commit to study protocol.

Exclusion Criteria:

• * Current marijuana tolerance, desire to cut down, or cravings to sue during periods of abstinence.
• * Strongly left-handed
• * Positive screen for drug or alcohol (except CNB) on test day will result in rescheduling the appointment
• * History of adverse effects with CNB
• * CNB users who are abstaining
• * Report of any psychotic disorder in a first degree relative
• * IQ \< 80 on the Wechsler Abbreviated Scale of Intelligence
• * Inability to comprehend written instructions using the WRAT-4 reading achievement test
• * Pregnant, breastfeeding, and ineffective birth control methods.
• * Unable or unsafe to have an MRI
• * Serious medical, neuro-ophthalmological, or neurological illness (e.g. cancer, seizure disorders, encephalopathy
• * History of head trauma with loss of consciousness \> 30 minutes or concussion lasting 30 days.
• * Focal brain lesion seen on structural MRI
• * Any medical/neurological condition that could compromise neurocognitive performance (e.g. epilepsy, multiple sclerosis, fetal alcohol syndrome).
• * Anyone deemed unsafe to study personnel for any reason