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THC Memory & Reward Learning Pilot

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ClinicalTrials.gov Identifier: NCT05116527
Recruitment Status : Recruiting
First Posted : November 11, 2021
Last Update Posted : August 5, 2022
Yale University
Information provided by (Responsible Party):
Godfrey Pearlson, Yale University

Tracking Information
First Submitted Date  ICMJE October 28, 2021
First Posted Date  ICMJE November 11, 2021
Last Update Posted Date August 5, 2022
Actual Study Start Date  ICMJE July 7, 2022
Estimated Primary Completion Date February 2024   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: November 8, 2021)
  • Marijuana induced performance changes on fMRI Multi-Stage Decision Making (MSDM) Task. [ Time Frame: Baseline and post drug administration at 10 minutes. ]
    The MSDM is a reinforcement learning paradigm that quantifies the degree to which subjects can integrate recent trial-to-trial information about a stimulus' likelihood of reward with acquired knowledge about whether some choices generally lead to disadvantageous outcomes vs. others that more often lead to reward.
  • Marijuana induced performance changes on Relational and Item Specific Coding (RISE) fMRI Task. [ Time Frame: Baseline and post drug administration at 10 minutes. ]
    The RISE task is a hippocampal-dependent learning paradigm that assesses declarative memory.
  • Marijuana induced performance changes on fMRI Treadway/Effort Reward Task. [ Time Frame: Baseline and post drug administration at 10 minutes. ]
    The Treadway Effort/Reward Task independently measures the neural responses to two dimensions of a cost/benefit decision: the effort required and the magnitude of reward.
  • Marijuana induced performance changes on fMRI Monetary Incentive Delay (MID) Task. [ Time Frame: Baseline and post drug administration at 10 minutes. ]
    The MID task probes the brain's reward system to assess the anticipation and receipt of rewards or punishment.
Original Primary Outcome Measures  ICMJE Same as current
Change History
Current Secondary Outcome Measures  ICMJE Not Provided
Original Secondary Outcome Measures  ICMJE Not Provided
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE THC Memory & Reward Learning Pilot
Official Title  ICMJE Pilot fMRI Studies of THC Effects on Memory and Reward Learning
Brief Summary Tetrahydrocannabidiol (THC) is the psychoactive chemical in cannabis that makes people high. This study aims to dissect acute impairment of various forms of memory and learning by THC in cannabis compared to placebo. Impairment will be assessed via a short cognitive test battery and then subjects will complete four tasks in the fMRI scanner.
Detailed Description

The protocol below is designed to begin dissecting acute impairment of various forms of memory and learning by THC in cannabis compared to placebo, in a 2-session per subject double-blind, random assignment, placebo-controlled counterbalanced design in young to middle-aged adults. The purpose of these experiments is to gather important pilot data to demonstrate proof of principle for a planned NIDA submission of a P50 center application that will examine cannabis's differential effects on the neural circuit underpinnings these various cognitive domains across the lifespan in much more detail. In other words, these pilot data will show NIDA that the investigators' methods and approaches work and are suitable for use in their proposed center grant application. Unlike in the planned P50, in these small-scale pilot studies the investigators are only concerned with comparing these disrupting effects using a single dose of THC versus placebo, without exploration of age, sleep, or sex-related differential effects or of different dose-related effects.

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. Although each of the fMRI tasks is already implemented in the investigators' lab in other contexts, the investigators have never studied alteration of the fMRI tasks by THC. Neither have other investigators elsewhere used this approach. It is also important to point out that the dose of active THC to be administered is the same as that already used safely in the investigators' IRB-approved driving studies, one which subjects state subjectively (a blind to actual dose information) makes them feel moderately intoxicated, and similar to the amount that they would consume themselves recreationally.

The study will consist of 3 days (screening visit and 2 dose days). In a randomized, counterbalanced, double-blind study, investigators will administer high THC marijuana or placebo marijuana using paced inhalation through a vaporizer. Following administration, subjects will provide subjectively-rated CNB intoxication using a verbal analog scale, a short cognitive test battery, then complete 4 fMRI paradigms within ~1.5 hours: a) MSDM task, b) MID task, c) RISE task, and d) Treadway Effort/Reward task. These tests will be counterbalanced across subjects and sessions to minimize order and fatigue effects.

Study Type  ICMJE Interventional
Study Phase  ICMJE Phase 1
Phase 2
Study Design  ICMJE Allocation: Randomized
Intervention Model: Crossover Assignment
Intervention Model Description:
All subjects will receive both study drug and placebo.
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Other
Condition  ICMJE
  • Marijuana
  • THC
  • Cannabis
Intervention  ICMJE
  • Drug: Marijuana, Hash, THC, or Grass
    Marijuana flower with a high THC content
    Other Names:
    • Marijuana
    • THC
  • Drug: Placebo
    Placebo THC - marijuana flower with no THC content
Study Arms  ICMJE
  • Experimental: High Dose THC
    Participants will receive high dose THC.
    Intervention: Drug: Marijuana, Hash, THC, or Grass
  • Experimental: Placebo THC
    Participants will receive placebo THC.
    Intervention: Drug: Placebo
Publications * Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Recruiting
Estimated Enrollment  ICMJE
 (submitted: November 8, 2021)
Original Estimated Enrollment  ICMJE Same as current
Estimated Study Completion Date  ICMJE February 2025
Estimated Primary Completion Date February 2024   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

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
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 18 Years to 55 Years   (Adult)
Accepts Healthy Volunteers  ICMJE Yes
Contacts  ICMJE
Contact: Suyash Adhikari, B.S 860-545-7106 Suyash.Adhikari@hhchealth.org
Contact: Diana King, B.A 860-545-7563 Diana.King@hhchealth.org
Listed Location Countries  ICMJE United States
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT05116527
Other Study ID Numbers  ICMJE HHC-2021-0195
Has Data Monitoring Committee Yes
U.S. FDA-regulated Product
Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
IPD Sharing Statement  ICMJE Not Provided
Current Responsible Party Godfrey Pearlson, Yale University
Original Responsible Party Same as current
Current Study Sponsor  ICMJE Hartford Hospital
Original Study Sponsor  ICMJE Same as current
Collaborators  ICMJE Yale University
Investigators  ICMJE
Principal Investigator: Godfrey Pearlson, M.D Yale University
PRS Account Hartford Hospital
Verification Date August 2022

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP