Pilot fMRI Studies of Aging-Related Effects of THC

Summary

The purpose of this study is to begin investigating acute impairment of various forms of memory and learning by Tetrahydrocannabinol (THC) in cannabis (CNB) compared to placebo, in a 2-session per subject double-blind, random assignment, placebo-controlled counterbalanced design in young to middle-aged adults.

Detailed Description

Tasks tapping each of the major cognitive memory-related domains will be performed in the MRI scanner, to reveal the relevant underlying circuitry and its disruption by drug using functional MRI. On an initial Screening Visit, regular or novice cannabis (CNB) users will undergo informed consent, clinical assessment (to fully evaluate inclusion/exclusion criteria), cognitive/personality assessment, and a structural MRI scan. At each assessment, subjects will provide subjectively-rated CNB intoxication using a verbal analog scale, complete 2 fMRI paradigms within \~1.5 hours: a) Card Guessing task and b) Complex Working Memory Span, and complete the computer-based Effort Expenditure for Reward Task within \~2 hours. These tests will be counterbalanced across subjects and sessions to minimize order and fatigue effects. Breaks will be standardized in a private environment and snacks/meals provided. Bathroom visits given as needed. Subjects will be supervised at all times by study staff and vital signs monitored. On assessment days, participants will remain at the Olin NRC until they report no subjective intoxication, and are observed by study staff to be no longer objectively intoxicated, then use taxi or Uber transportation home.

Eligibility Criteria

Interventions