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Updated: Sep 14, 2025

Brain Morphology of Cannabis Users With or Without Psychosis: A Pilot MRI Study
Published on: August 18, 2020
Development of a motivational enhancement therapy cannabis-reduction intervention for young adults experiencing
Denise D Walker1, Ryan Petros1, Melanie Bennett2
1School of Social Work, University of Washington.
Objective:
Cannabis use is common among young adults experiencing psychosis (YA-P) and is associated with negative consequences. Effective cannabis interventions for YA-P have not been identified. The Teen Marijuana Check-Up is a two-session intervention to reduce heavy cannabis use in YA-P who are not seeking cannabis treatment. We used data from interviews and focus groups to optimize the Teen Marijuana Check-Up for YA-P and conducted a demonstration project of this optimized intervention-the Cannabis Check-Up for Psychosis (CCU-P)-to evaluate its acceptability and feasibility.
Methods:
Findings from qualitative interviews and focus groups were used to design optimizations that were reviewed by a Stakeholder Advisory Board for feedback. The final CCU-P was evaluated in a one-arm pilot study with 12 YA-P who were regular cannabis consumers and engaged in Coordinated Specialty Care. Feasibility (tracking participation) and acceptability (satisfaction ratings, qualitative input) were evaluated.
Results:
Optimizations included (a) questions to elicit discussion of cannabis' impact on mental health, psychosis, and treatment; (b) data-based comparisons with infographics to inform about risks for rehospitalization and challenges to recovery associated with cannabis use; and (c) an infographic to detail harm reduction strategies. Overall, 92% completed both CCU-P sessions. Intervention satisfaction was high. All participants reported that they would recommend CCU-P to others in Coordinated Specialty Care.
Conclusions And Implications For Practice:
CCU-P is a promising intervention, resonant with principles of psychiatric rehabilitation, that uses a nonjudgmental approach, provides science-based information about cannabis-psychosis interactions, and supports participants to make informed choices about use. A larger efficacy trial is warranted. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

