Marijuana alters the human cerebellar clock.
Daniel S O'Leary, Robert I Block, Beth M Turner, Julie A Koeppel, Vincent A Magnotta, Laura L. Boles Ponto, G Leonard Watkins, Richard D Hichwa, Nancy C Andreasen
Neuroreport June 11, 2003 DOI: 10.1097/00001756-200306110-00009 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 24 |
| Population | Occasional and chronic marijuana smokers |
| Intervention | Marijuana |
| Topics | Cannabis |
| Key findings | Smoking marijuana increased rCBF in the ventral forebrain and cerebellar cortex in both occasional and chronic users, but chronic users showed less frontal lobe activation. Counting and tapping rates increased after marijuana, correlating with cerebellar rCBF, suggesting marijuana accelerates a cerebellar clock. |
Abstract
The effects of marijuana on brain perfusion and internal timing were assessed using [15O] water PET in occasional and chronic users. Twelve volunteers who smoked marijuana recreationally about once weekly, and 12 volunteers who smoked daily for a number of years performed a self-paced counting task during PET imaging, before and after smoking marijuana and placebo cigarettes. Smoking marijuana increased rCBF in the ventral forebrain and cerebellar cortex in both groups, but resulted in significantly less frontal lobe activation in chronic users. Counting rate increased after smoking marijuana in both groups, as did a behavioral measure of self-paced tapping, and both increases correlated with rCBF in the cerebellum. Smoking marijuana appears to accelerate a cerebellar clock altering self-paced behaviors.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |
Citations in the library
Cited by 21
- Antidepressant-like activity and modulation of brain monoaminergic transmission by blockade of anandamide hydrolysis Proceedings of the National Academy of Sciences December 13, 2005
- Neuroimaging in cannabis use: a systematic review of the literature Psychological Medicine July 23, 2009
- Effects of Cannabis on Impulsivity: A Systematic Review of Neuroimaging Findings Current Pharmaceutical Design May 10, 2014
- Delta-9-Tetrahydrocannabinol Disruption of Time Perception and of Self-Timed Actions Pharmacopsychiatry July 22, 2010
- Task-independent acute effects of delta-9-tetrahydrocannabinol on human brain function and its relationship with cannabinoid receptor gene expression: a neuroimaging meta-regression analysis bioRxiv (Cold Spring Harbor Laboratory) November 3, 2021
and 16 more in the library
Cites 3
- Effects of smoking marijuana on brain perfusion and cognition. Neuropsychopharmacology June 2002
- Cerebellar activity and disturbed time sense after THC. Brain Research June 29, 1998
- Brain glucose metabolism in chronic marijuana users at baseline and during marijuana intoxication. Psychiatry Research May 31, 1996