ArticleBehavioural brain research2015
Combined effects of marijuana and nicotine on memory performance and hippocampal volume.
Article in Behavioural brain research, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 40 papers, 3 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
40 citing papers in PubMed, 3 syntheses or guidelines pooled it, 69 citations in OpenAlex.
- The Influence of Cannabis and Nicotine Co-use on Neuromaturation: A Systematic Review of Adolescent and Young Adult Studies.Biological psychiatry · 2021Pooled it
- Does regular cannabis use affect neuroanatomy? An updated systematic review and meta-analysis of structural neuroimaging studies.European archives of psychiatry and clinical neuroscience · 2019Pooled it
- Association of Cannabis With Cognitive Functioning in Adolescents and Young Adults: A Systematic Review and Meta-analysis.JAMA psychiatry · 2018Pooled it
- Co-use of cannabis and tobacco in the same occasion: Acute effects. A systematic review.Psychopharmacology · 2026Review
- Assessment of nicotine and cannabis co-use among adolescents and the association with nicotine and cannabis dependence symptoms.Addictive behaviors · 2025Article
- A Naturalistic Examination of the Acute Effects of High-Potency Cannabis on Emotion Regulation Among Young Adults: A Pilot Study.Human psychopharmacology · 2025Article
- The Combined Effects of Nicotine and Cannabis on Cortical Thickness Estimates in Adolescents and Emerging Adults.Brain sciences · 2024Article
- Nicotine use during late adolescence and young adulthood is associated with changes in hippocampal volume and memory performance.Frontiers in neuroscience · 2024Article
- HIV chronicity as a predictor of hippocampal memory deficits in daily cannabis users living with HIV.Drug and alcohol dependence reports · 2023Article
- Altered brain structural and functional connectivity in cannabis users.Scientific reports · 2023Article
- Testing the consequences of alcohol, cannabis, and nicotine use on hippocampal volume: a quasi-experimental cotwin control analysis of young adult twins.Psychological medicine · 2023Article
- Nicotine Dependence among Current Cigarette Smokers Who Use E-Cigarettes and Cannabis.Substance use & misuse · 2023Article
- E-cigarettes may serve as a gateway to conventional cigarettes and other addictive drugs.Advances in drug and alcohol research · 2023Review
- Differences between adults who smoke cigarettes daily and do and do not co-use cannabis: Findings from the 2020 ITC four country smoking and vaping survey.Addictive behaviors · 2022Article
- Prefrontal cortex and putamen grey matter alterations in cannabis and tobacco users.Journal of psychopharmacology (Oxford, England) · 2022Article
- Young Adult E-Cigarette and Combustible Tobacco Users Attitudes, Substance Use Behaviors, Mental Health, and Neurocognitive Performance.Brain sciences · 2022Article
- Unraveling the role of cigarette use in neural cannabis cue reactivity in heavy cannabis users.Addiction biology · 2021Article
- Concurrent E-cigarette and marijuana use and health-risk behaviors among U.S. high school students.Preventive medicine · 2021Article
- Co-occurring tobacco and cannabis use in adolescents: Dissociable relationships with mediofrontal electrocortical activity during reward feedback processing.NeuroImage. Clinical · 2021Article
- Independent and Combined Effects of Nicotine or Chronic Tobacco Smoking and HIV on the Brain: A Review of Preclinical and Clinical Studies.Journal of neuroimmune pharmacology : the official journal of the Society on NeuroImmune Pharmacology · 2020Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors at 1 institution in 1 country.
Funding
Abstract
Combined use of marijuana (MJ) and tobacco is highly prevalent in today's population. Individual use of either substance is linked to structural brain changes and altered cognitive function, especially with consistent reports of hippocampal volume deficits and poorer memory performance. However, the combined effects of MJ and tobacco on hippocampal structure and on learning and memory processes remain unknown. In this study, we examined both the individual and combined effects of MJ and tobacco on hippocampal volumes and memory performance in four groups of adults taken from two larger studies: MJ-only users (n=36), nicotine-only (Nic-only, n=19), combined marijuana and nicotine users (MJ+Nic, n=19) and non-using healthy controls (n=16). Total bilateral hippocampal volumes and memory performance (WMS-III logical memory) were compared across groups controlling for total brain size and recent alcohol use. Results found MJ and MJ+Nic groups had smaller total hippocampal volumes compared to Nic-only and controls. No significant difference between groups was found between immediate and delayed story recall. However, the controls showed a trend for larger hippocampal volumes being associated with better memory scores, while MJ+Nic users showed a unique inversion, whereby smaller hippocampal volume was associated with better memory. Overall, results suggest abnormalities in the brain-behavior relationships underlying memory processes with combined use of marijuana and nicotine use. Further research will need to address these complex interactions between MJ and nicotine.
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What OpenQuestion holds
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.