ArticleNeuropsychopharmacology : official publication of the American College of Neuropsychopharmacology2014
Long-term effects of cannabis on brain structure.
Article in Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 140 papers, 9 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
140 citing papers in PubMed, 9 syntheses or guidelines pooled it, 346 citations in OpenAlex.
- The genetics of cannabis lifetime use.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2026Pooled it
- The impact of cannabis use on erectile dysfunction and sex hormones: a Mendelian randomization analysis.International journal of impotence research · 2025Pooled it
- Systematic review of structural and functional neuroimaging studies of cannabis use in adolescence and emerging adulthood: evidence from 90 studies and 9441 participants.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2022Pooled it
- How do substance use disorders compare to other psychiatric conditions on structural brain abnormalities? A cross-disorder meta-analytic comparison using the ENIGMA consortium findings.Human brain mapping · 2022Pooled it
- Genetic basis of cannabis use: a systematic review.BMC medical genomics · 2021Pooled it
- The Influence of Cannabis and Nicotine Co-use on Neuromaturation: A Systematic Review of Adolescent and Young Adult Studies.Biological psychiatry · 2021Pooled it
- Gray and white matter morphology in substance use disorders: a neuroimaging systematic review and meta-analysis.Translational psychiatry · 2021Pooled it
- Age- and Sex-Related Cortical Gray Matter Volume Differences in Adolescent Cannabis Users: A Systematic Review and Meta-Analysis of Voxel-Based Morphometry Studies.Frontiers in psychiatry · 2021Pooled it
- A large-scale genome-wide association study meta-analysis of cannabis use disorder.The lancet. Psychiatry · 2020Pooled it
- Randomized controlled internal pilot trial of a diversion programme for adolescents in police custody who possess illicit substances.Journal of public health (Oxford, England) · 2024Trial
- Emerging adult perceptions of higher-risk cannabis consumption behaviours.Harm reduction journal · 2023Trial
- Reduced responsiveness of the reward system is associated with tolerance to cannabis impairment in chronic users.Addiction biology · 2021Trial
- Prospective Volumetric Changes in the Thalamus in Adolescent First Episode of Mania and Cannabis Use: A Preliminary Study.Bipolar disorders · 2026Article
- Genetic pleiotropy differentially linking brain variation to cannabis use and cannabis use disorder.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2026Article
- Memory impairment and chronic high-dose Δ9-THC/cannabis exposure: a narrative review of molecular mechanisms underlying neurotoxic effects.Psychopharmacology · 2026Review
- Multimodal MRI Reveals Brain Structural Differences and Executive Dysfunction in Early Methamphetamine Abstinence.Brain and behavior · 2026Article
- An astrocytic ensemble at vHip-NAc synapses modulates cognitive impairments induced by chronic tetrahydrocannabinol exposure.Nature communications · 2025Article
- Article
- Unraveling the Enigma of Cannabinoid Hyperemesis Syndrome: A Narrative Review of Diagnosis and Management.Cureus · 2025Review
- Measuring the Associations Between Brain Morphometry and Polygenic Risk Scores for Substance use Disorders in Drug-Naive Adolescents.Behavior genetics · 2025Article
80 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
10 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The dose-dependent toxicity of the main psychoactive component of cannabis in brain regions rich in cannabinoid CB1 receptors is well known in animal studies. However, research in humans does not show common findings across studies regarding the brain regions that are affected after long-term exposure to cannabis. In the present study, we investigate (using Voxel-based Morphometry) gray matter changes in a group of regular cannabis smokers in comparison with a group of occasional smokers matched by the years of cannabis use. We provide evidence that regular cannabis use is associated with gray matter volume reduction in the medial temporal cortex, temporal pole, parahippocampal gyrus, insula, and orbitofrontal cortex; these regions are rich in cannabinoid CB1 receptors and functionally associated with motivational, emotional, and affective processing. Furthermore, these changes correlate with the frequency of cannabis use in the 3 months before inclusion in the study. The age of onset of drug use also influences the magnitude of these changes. Significant gray matter volume reduction could result either from heavy consumption unrelated to the age of onset or instead from recreational cannabis use initiated at an adolescent age. In contrast, the larger gray matter volume detected in the cerebellum of regular smokers without any correlation with the monthly consumption of cannabis may be related to developmental (ontogenic) processes that occur in adolescence.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.