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Brain Morphology of Cannabis Users With or Without Psychosis: A Pilot MRI Study
Published on: August 18, 2020
Abstinent adolescent marijuana users show altered fMRI response during spatial working memory.
Alecia D Schweinsburg1, Bonnie J Nagel, Brian C Schweinsburg
1University of California San Diego, Department of Psychology, 9500 Gilman Dr., 0109, La Jolla, CA 92093-0109, USA.
Psychiatry Research
|March 22, 2008
Summary
Heavy marijuana use in adolescents may cause lasting brain changes. Even after a month of abstinence, marijuana-using teens showed altered brain activity during memory tasks compared to non-users.
Area of Science:
- Neuroscience
- Adolescent Psychology
- Neuroimaging
Background:
- Marijuana is the most prevalent illicit substance among adolescents.
- Limited understanding exists regarding the neural impacts of heavy adolescent marijuana use.
- Previous research indicated altered brain activity in adolescent marijuana users after short abstinence periods.
Purpose of the Study:
- To investigate the persistent neurocognitive effects of heavy marijuana use in adolescents.
- To examine functional magnetic resonance imaging (fMRI) responses during spatial working memory (SWM) in abstinent adolescent marijuana users.
Main Methods:
- 15 marijuana-using (MJ) teens and 17 non-using controls (ages 16-18) participated.
- Participants maintained 28 days of abstinence, verified by biweekly urine toxicology screens.
- fMRI scans were acquired during a spatial working memory task.
Main Results:
- Despite similar task performance, MJ teens exhibited reduced activity in the right dorsolateral prefrontal and occipital cortices.
- MJ teens showed significantly increased activation in the right posterior parietal cortex.
- Abnormal brain activity patterns were observed in MJ teens even after one month of abstinence.
Conclusions:
- Heavy marijuana use during adolescence is associated with persistent abnormalities in brain response during SWM tasks.
- Altered activation patterns may suggest changes in spatial rehearsal and attention strategies.
- Findings indicate potential alterations in neurodevelopment or lasting neural changes linked to adolescent marijuana consumption.
