Cognitive Recovery With Cannabis Abstinence Among High School-Aged Adolescents

January 3, 2024 updated by: Randi Melissa Schuster, Massachusetts General Hospital
This study will use a randomized controlled design to test whether 30 days of cannabis abstinence, compared to 30 days of monitoring, is associated with improvements in cognitive functioning. Non-using controls will also be enrolled to determine the clinical significance of any cognitive improvements with abstinence.

Study Overview

Status

Completed

Intervention / Treatment

Detailed Description

This is a 5-year randomized, longitudinal trial of cannabis abstinence designed to determine (1) if performance improves with abstinence beyond that observed with continued cannabis use, and if so, (2) when during abstinence cognitive improvement occurs, and (3) whether performance in abstinent individuals "returns" to performance levels observed in non-using peers. We hypothesized that abstinent adolescent cannabis users would have more neurocognitive improvement over four weeks compared to non-abstinent cannabis users, and performance would continuously improve throughout four weeks of abstinence. We will recruit 210 adolescents with and without regular cannabis use. Eligible cannabis users will be randomized to either a contingency management intervention which will incentivize 4 weeks of cannabis abstinence (n = 70), or non-contingent monitoring with no abstinence requirement (n = 70). All participants (including non-users; n = 70) will complete cognitive assessments, toxicology testing, self-report questionnaires and semi-structured mood and substance use interviews during the 4-week study as well as one 30-day follow-up visit. Abstinence will be indexed by decreasing levels of cannabis metabolites in urine.

Study Type

Interventional

Enrollment (Actual)

201

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Massachusetts General Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

13 years to 19 years (Child, Adult)

Accepts Healthy Volunteers

Yes

Description

General Inclusion Criteria for School-Aged Study Component:

  • Male and female adolescents from the Boston area who are between the ages of 10 and 19 (inclusive);
  • Have a parent or legal guardian who is able and willing to provide written informed consent for the active study phase (if under the age of 18);
  • Competent and willing to provide written informed assent for the active study phase (if under the age of 18);
  • Competent and able to provide written informed consent (if age 18 or older)
  • Able to communicate in English language
  • Able to commit to 9 study visits in approximately 60 days
  • No severe developmental delays (including, but not limited to, Autism Spectrum Disorder, Intellectual Disability, and Down Syndrome)
  • Able to safely participate in the protocol and appropriate for outpatient level of care

Cannabis-Using Group Inclusion Criteria:

  • Use of cannabis at least once per week on most weeks
  • Cannabis use reported within 7 days of both baseline visits
  • No immediate plan to discontinue cannabis use

Non-Using Group Inclusion Criteria:

  • Use of cannabis less than 5 times in lifetime
  • No cannabis use in the past year
  • No cannabis use before age 16

Exclusion Criteria for School-Aged Study Component

- Passive consent for initial school-wide assessment withdrawn by parent or legal guardian or written parental consent not provided prior to screening

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Other
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Abstinent
This group of cannabis users are agree to remain abstinent from cannabis use for 30 days.
Cannabis users randomized to this condition will be enrolled in a contingency management intervention for 30 days of cannabis abstinence.
Other Names:
  • Contingency Management
No Intervention: Monitoring
This group of cannabis users are not asked to change their cannabis use behavior.
No Intervention: Non-Users
This is a group of adolescents with little to no cannabis use history and is non-randomized.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Mean Difference in the Total Number of Errors From Paired Associates Learning (PAL) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The number of times the subject chose the incorrect box for a stimulus on assessment problems plus an adjustment for the estimated number of errors they would have made on any problems/attempts/recalls they did not reach. This is a specific measure from the Paired Associates Learning (PAL) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The PAL module assesses visual memory and new learning. Count variable, ranging from 0 to 70, where higher scores indicate more errors and worse performance.
1, 2, 3, and 4 Weeks
Mean Difference in First Attempt Memory Score From Paired Associates Learning (PAL) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The number of times a subject chose the correct box on their first attempt when recalling pattern locations, which was calculated across all trials. This is a specific measure from the Paired Associates Learning (PAL) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The PAL module assesses visual memory and new learning. Count variable, ranging from 0 to 20, where higher scores indicate better memory performance.
1, 2, 3, and 4 Weeks
Mean Difference in Forward Span Length From Spatial Span (SSP) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The longest length of sequences (spans) a subject successfully remembered in the original order. This is a specific measure from the Spatial Span (SSP) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The SSP assesses visuospatial working memory capacity. Count variable, ranging from 2 to 9, with higher scores indicating better memory performance.
1, 2, 3, and 4 Weeks
Mean Difference in Reverse Span Length From Spatial Span (SSP) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The longest length of sequences (spans) a subject successfully remembered in the reverse order. This is a specific measure from the Spatial Span (SSP) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The SSP assesses visuospatial working memory capacity. Count variable, ranging from 2 to 9, with higher scores indicating better memory performance.
1, 2, 3, and 4 Weeks
Mean Difference in the Total Number Correct in the Immediate Recall Measure From the Verbal Recognition Memory (VRM) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The total number of distinct words a subject correctly recalled from the studied list of 18 words during the immediate free recall phase. This is a specific measure from the Verbal Recognition Memory (VRM) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The VRM module assesses verbal memory and new learning. Count variable, ranging from 0 to 18, with higher scores indicating better immediate recall performance.
1, 2, 3, and 4 Weeks
Mean Difference in the Total Number Correct in the Delayed Recall Measure From the Verbal Recognition Memory (VRM) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The total number of distinct words a subject correctly recalled from the studied list of 18 words during the delayed free recall phase. This is a specific measure from the Verbal Recognition Memory (VRM) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The VRM module assesses verbal memory and new learning. Count variable, ranging from 0 to 18, with higher scores indicating better immediate recall performance.
1, 2, 3, and 4 Weeks
Mean Difference in the Total Number Correct in the Immediate Recognition Condition From the Verbal Recognition Memory (VRM) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The total number of words a subject correctly identified as either previously studied or novel during the immediate recognition phase. This is a specific measure from the Verbal Recognition Memory (VRM) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The VRM module assesses verbal memory and new learning. Count variable, ranging from 0 to 36, with higher scores indicating better recognition memory performance.
1, 2, 3, and 4 Weeks
Mean Difference in the Total Number Correct in the Delayed Recognition Condition From the Verbal Recognition Memory (VRM) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The total number of words a subject correctly identified as either previously studied or novel during the delayed recognition phase. This is a specific measure from the Verbal Recognition Memory (VRM) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The VRM module assesses verbal memory and new learning. Count variable, ranging from 0 to 36, with higher scores indicating better recognition memory performance.
1, 2, 3, and 4 Weeks
Mean Difference in the Total Number Incorrect From the Multitasking Test (MTT) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The total number of words a subject correctly identified as either previously studied or novel during the delayed recognition phase. This is a specific measure from the Multitasking Test (MTT) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The MTT assesses the participant's ability to manage conflicting information provided by the direction of an arrow and its location on the screen and to ignore task-irrelevant information. Count variable, ranging from 0 to 160, with higher scores indicating more errors and worse performance.
1, 2, 3, and 4 Weeks
Mean Difference in the Response Latency From the Multitasking Test (MTT) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The response latency for each participant was defined as a summary (median) computed over their response times for all correct responses irrespective of condition. This is a specific measure from the Multitasking Test (MTT) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The MTT assesses the participant's ability to manage conflicting information provided by the direction of an arrow and its location on the screen and to ignore task-irrelevant information. Response time variable in milliseconds (ms), ranging from 100 to 2000 ms, with higher values indicating slower performance across all trials.
1, 2, 3, and 4 Weeks
Mean Difference in the Incongruency Cost From the Multitasking Test (MTT) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The incongruency cost for each participant was defined as a summary (median) of response times for incongruent trials minus a summary (median) of response times for congruent trials. This is a specific measure from the Multitasking Test (MTT) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The MTT assesses the participant's ability to manage conflicting information provided by the direction of an arrow and its location on the screen and to ignore task-irrelevant information. Difference score in milliseconds (ms), ranging from -1900 to 1900 ms, with higher values indicating slower responses on incongruent trials, suggesting that it takes longer to process conflicting information.
1, 2, 3, and 4 Weeks
Mean Difference in the Multitasking Cost From the Multitasking Test (MTT) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The multitasking cost for each participant was defined as a summary (median) of response times for the multi-task blocks (trials alternated between having to respond to the direction or position of the arrow) minus a summary (median) of response times for the single-task blocks (all trials consisted of either responding to the direction or position of the arrow). This is a specific measure from the Multitasking Test (MTT) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The MTT assesses the participant's ability to manage conflicting information provided by the direction of an arrow and its location on the screen and to ignore task-irrelevant information. Difference score in milliseconds (ms), ranging from -1900 to 1900 ms, with higher values indicating slower responses on multi-task blocks, suggesting that it takes longer to process multiple sources of information.
1, 2, 3, and 4 Weeks
Mean Difference in Number of Problems Correctly Solved on the First Choice From the One Touch Stockings of Cambridge (OTS) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The total number of trials where the subject chose the correct answer on the first attempt. This is a specific measure from the One Touch Stockings of Cambridge (OTS) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The OTS module assesses executive function based upon the Tower of Hanoi test. Count variable, ranging from 0 to 15, with higher scores indicating better performance.
1, 2, 3, and 4 Weeks
Mean Difference in the Latency to First Correct Choice From the One Touch Stockings of Cambridge (OTS) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The latency to first correct choice for each participant was defined as a summary (median) of the response times for all trials in which the subject picked the correct choice on the first attempt. This is a specific measure from the One Touch Stockings of Cambridge (OTS) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The OTS module assesses executive function based upon the Tower of Hanoi test. Response time variable in milliseconds (ms), a positive unbounded variable, with higher values indicating slower performance across correct trials.
1, 2, 3, and 4 Weeks
Mean Difference in Stop Signal Reaction Time From Stop Signal Task (SST) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The estimate of the duration at which a person can successfully inhibit a response 50% of the time, represents the time before which all actions become ballistic and a subject is unable to cancel a response selection. This is a specific measure from the Stop Signal Task (SST) Module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The SST module assesses response inhibition (impulse control). Response time variable in milliseconds (ms), ranging from 0 to 500 ms, with higher values indicating that it takes longer for a person to inhibit a response.
1, 2, 3, and 4 Weeks
Mean Difference in the Total Number of Between Errors From the Spatial Working Memory (SWM) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The number of times a subject incorrectly revisited a box that had contained a token in a previous trial across the 4, 6, and 8 box conditions. This is a specific measure from the Spatial Working Memory (SWM) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The SWM module provides a measure of strategy as well as working memory errors. Count variable, ranging from 0 to 63, with higher scores indicating worse performance.
1, 2, 3, and 4 Weeks
Mean Difference in the Participant's Strategy for 6-8 Box Conditions From the Spatial Working Memory (SWM) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The number of times subjects began a new search from the same box they started on in previous trials. It is assumed that a person who begins from the same box each time is using a planned strategy to find the tokens. This is a specific measure from the Spatial Working Memory (SWM) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The SWM module provides a measure of strategy as well as working memory errors. Count variable, ranging from 2 to 14, with higher scores indicating low strategy, meaning a subject began searches from many different boxes.
1, 2, 3, and 4 Weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Mean Difference in the Measure of Discriminability - A' From the Rapid Visual Information Processing (RVP) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
A transformation of the proportion of hits and false alarms, providing an estimate of a subject's ability to detect the target sequences of digits after controlling for response bias (i.e., biases to respond or not respond irrespective of the stimuli on screen). This is a specific measure from the Rapid Visual Information Processing (RVP) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The RVP module assesses sustained attention. Bounded continuous variable, ranging from 0 to 1, where higher scores indicate a greater ability to discriminate between targets and distractors.
1, 2, 3, and 4 Weeks
Mean Difference in the Reponse Latency for Hits From the Rapid Visual Information Processing (RVP) Module Averaged Over Weeks 1, 2, 3, and 4
Time Frame: 1, 2, 3, and 4 Weeks
The response latency for hits for each participant was defined as a summary (median) over the set of response times for all correct responses (identification of target 3-digit sequences). This is a specific measure from the Rapid Visual Information Processing (RVP) module, which is part of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The RVP module assesses sustained attention. Response time variable in milliseconds (ms), ranging from 100 to 1900 ms, with higher values indicating slower performance in detecting targets.
1, 2, 3, and 4 Weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Randi M Schuster, PhD, Massachusetts General Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

August 7, 2017

Primary Completion (Actual)

November 9, 2022

Study Completion (Actual)

November 9, 2022

Study Registration Dates

First Submitted

September 6, 2017

First Submitted That Met QC Criteria

September 6, 2017

First Posted (Actual)

September 8, 2017

Study Record Updates

Last Update Posted (Estimated)

February 1, 2024

Last Update Submitted That Met QC Criteria

January 3, 2024

Last Verified

January 1, 2024

More Information

Terms related to this study

Other Study ID Numbers

  • 1K23DA042946 (U.S. NIH Grant/Contract)

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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