ArticleNeuropsychology2015
Neuropsychological performance in adolescent marijuana users with co-occurring alcohol use: A three-year longitudinal study.
Article in Neuropsychology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 54 papers, 1 of them a synthesis that pooled it.
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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.
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Who cites it
54 citing papers in PubMed, 1 synthesis or guideline pooled it, 75 citations in OpenAlex.
- Association of Cannabis With Cognitive Functioning in Adolescents and Young Adults: A Systematic Review and Meta-analysis.JAMA psychiatry · 2018Pooled it
- A multi-site proof-of-concept investigation of computerized approach-avoidance training in adolescent cannabis users.Drug and alcohol dependence · 2018Trial
- Alcohol use during a trial of N-acetylcysteine for adolescent marijuana cessation.Addictive behaviors · 2016Trial
- Longitudinal neurocognitive trajectories in a large cohort of youth who use cannabis: combining self-report and toxicology.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2026Article
- How does cognition change over time in young people who use cannabis recreationally? A narrative review of the longitudinal literature to date.Psychopharmacology · 2026Review
- Longitudinal Neurocognitive Trajectories in a Large Cohort of Youth Who Use Cannabis: Combining Self-Report and Toxicology.bioRxiv : the preprint server for biology · 2026Article
- A Fine-Grained Longitudinal Study of Adolescent Cannabis Use and Its Relation to Cognitive Performance in Young Adulthood.International journal of mental health and addiction · 2026Article
- Adolescents' experiences with substance use: risks, protective factors and interventions.BMC psychology · 2025Article
- Residual and enduring effects of cannabis use on cognitive and psychomotor function: A study of adults during unrestricted cannabis use, short-term abstinence, and protracted abstinence.Experimental and clinical psychopharmacology · 2025Article
- The effects of moderate alcohol and THC co-use during male and female rat adolescence on AKT-GSK3ß signaling in adulthood.Behavioural brain research · 2025Article
- Network topology and cannabis use following two weeks of monitored abstinence: moderation of sex and patterns of use findings.Frontiers in adolescent medicine · 2025Article
- Cannabis use and neurocognitive performance at 13-14 Years-Old: Optimizing assessment with hair toxicology in the Adolescent brain cognitive development (ABCD) study.Addictive behaviors · 2024Article
- Cannabis use may attenuate neurocognitive performance deficits resulting from methamphetamine use disorder.Journal of the International Neuropsychological Society : JINS · 2024Article
- Patterns of Simultaneous and non-Simultaneous Use of Cannabis and Alcohol Among American Indian Adolescents.Addiction research & theory · 2024Article
- Effects of combined exposure to ethanol and delta-9-tetrahydrocannabinol during adolescence on synaptic plasticity in the prefrontal cortex of Long Evans rats.Neuropharmacology · 2024Article
- Developmental trajectories of alcohol and cannabis concurrent use in a nationally representative sample of United States youths.Drug and alcohol dependence · 2023Article
- Cognitive Alterations in Addictive Disorders: A Translational Approach.Biomedicines · 2023Review
- Ratings of executive function as a risk factor for adolescents' frequent cannabis use: A prospective longitudinal study.Psychology of addictive behaviors : journal of the Society of Psychologists in Addictive Behaviors · 2023Article
- Associations between alcohol and cannabis use order, frequency, quantity, and consequences in a college sample of individuals who co-use alcohol and cannabis.The American journal on addictions · 2023Article
- A 2-year follow-up of the effects of combined binge drinking and cannabis consumption on academic performance and adjustment in Spanish third-year university students.Frontiers in psychology · 2023Article
Corrections and comments
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Authors and funding
7 authors at 3 institutions in 1 country.
Funding
Abstract
objectiveThe effect of adolescent marijuana use on brain development remains unclear despite relaxing legal restrictions, decreased perceived harm, and increasing use rates among youth. The aim of this 3-year prospective study was to evaluate the long-term neurocognitive effects of adolescent marijuana use.
methodAdolescent marijuana users with concomitant alcohol use (MJ + ALC, n = 49) and control teens with limited substance use histories (CON, n = 59) were given neuropsychological and substance use assessments at project baseline, when they were ages 16-19. They were then reassessed 18 and 36 months later. Changes in neuropsychological measures were evaluated with repeated measures analysis of covariance (ANCOVA), controlling for lifetime alcohol use, and examined the effects of group, time, and group by time interactions on cognitive functioning.
resultsMJ + ALC users performed significantly worse than controls, across time points, in the domains of complex attention, memory, processing speed, and visuospatial functioning (ps <.05). Earlier age of marijuana use onset was associated with poorer processing speed and executive functioning by the 3-year follow-up (ps ≤.02).
conclusionsFrequent marijuana use throughout adolescence and into young adulthood appeared linked to worsened cognitive performance. Earlier age of onset appears to be associated with poorer neurocognitive outcomes that emerge by young adulthood, providing further support for the notion that the brain may be uniquely sensitive to frequent marijuana exposure during the adolescent phase of neurodevelopment. Continued follow-up of adolescent marijuana users will determine the extent of neural recovery that may occur if use abates.
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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.