ArticleNeuropsychology2016
Early onset marijuana use is associated with learning inefficiencies.
Article in Neuropsychology, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 25 papers, 1 of them a synthesis 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.
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Who cites it
25 citing papers in PubMed, 1 synthesis or guideline pooled it, 48 citations in OpenAlex.
- The effects of cannabinoid 1 receptor compounds on memory: a meta-analysis and systematic review across species.Psychopharmacology · 2019Pooled it
- One Month of Cannabis Abstinence in Adolescents and Young Adults Is Associated With Improved Memory.The Journal of clinical psychiatry · 2018Trial
- Age patterns and predictors of cannabis initiation among biracial and monoracial U.S. youth.The American journal of drug and alcohol abuse · 2025Article
- Age of tobacco, nicotine and cannabis use initiation in Switzerland: a sequence analysis among adolescents and young adults.BMC public health · 2024Article
- Longitudinal Associations Between Cannabis Use and Cognitive Impairment in a Clinical Sample of Middle-Aged Adults Using Cannabis for Medical Symptoms.Cannabis and cannabinoid research · 2024Article
- Prospective, longitudinal study to isolate the impacts of marijuana use on neurocognitive functioning in adolescents.Frontiers in psychiatry · 2023Article
- The International Cannabis Toolkit (iCannToolkit): a multidisciplinary expert consensus on minimum standards for measuring cannabis use.Addiction (Abingdon, England) · 2022Article
- Retrospective Recall of Marijuana Use Patterns Following the COVID-19 Outbreak Vary as a Function of User Type Among Adolescents in Washington State.Cannabis (Albuquerque, N.M.) · 2022Article
- The externalizing and internalizing pathways to marijuana use initiation: Examining the synergistic effects of impulsiveness and sensation seeking.Developmental psychology · 2021Article
- Sex Differences in Neuropsychological Functioning are Domain-Specific in Adolescent and Young Adult Regular Cannabis Users.Journal of the International Neuropsychological Society : JINS · 2021Article
- Attitudes, Subjective Norms, and Perceived Behavioral Control Associated with Age of First Use of Cannabis among Adolescents.The Journal of school health · 2021Article
- Recreational cannabis use impairs driving performance in the absence of acute intoxication.Drug and alcohol dependence · 2020Article
- Review
- Age, period and cohort effects in frequent cannabis use among US students: 1991-2018.Addiction (Abingdon, England) · 2019Article
- The initiation of cannabis use in adolescence is predicted by sex-specific psychosocial and neurobiological features.The European journal of neuroscience · 2019Article
- Marijuana use and major depressive disorder are additively associated with reduced verbal learning and altered cortical thickness.Cognitive, affective & behavioral neuroscience · 2019Article
- Marijuana use associated with worse verbal learning and delayed recall in a sample of young adults.Revista medica de Chile · 2019Article
- College degree attainment by age of first marijuana use and parental education.Substance abuse · 2019Article
- Do Differences in Learning Performance Precede or Follow Initiation of Marijuana Use?Journal of studies on alcohol and drugs · 2019Article
- Prevalence and Sociodemographic Correlates of Adolescent Use and Polyuse of Combustible, Vaporized, and Edible Cannabis Products.JAMA network open · 2018Article
Corrections and comments
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Authors and funding
4 authors at 1 institution in 1 country.
Funding
Abstract
objectiveVerbal memory difficulties are the most widely reported and persistent cognitive deficit associated with early onset marijuana use. Yet, it is not known what memory stages are most impaired in those with early marijuana use.
methodForty-eight young adults, aged 18-25, who used marijuana at least once per week and 48 matched nonusing controls (CON) completed the California Verbal Learning Test, Second Edition (CVLT-II). Marijuana users were stratified by age of initial use: early onset users (EMJ), who started using marijuana at or before age 16 (n = 27), and late onset marijuana user group (LMJ), who started using marijuana after age 16 (n = 21). Outcome variables included trial immediate recall, total learning, clustering strategies (semantic clustering, serial clustering, ratio of semantic to serial clustering, and total number of strategies used), delayed recall, and percent retention.
resultsLearning improved with repetition, with no group effect on the learning slope. EMJ learned fewer words overall than LMJ or CON. There was no difference between LMJ and CON in total number of words learned. Reduced overall learning mediated the effect on reduced delayed recall among EMJ, but not CON or LMJ. Learning improved with greater use of semantic versus serial encoding, but this did not vary between groups. EMJ was not related to delayed recall after adjusting for encoding.
conclusionsYoung adults reporting early onset marijuana use had learning weaknesses, which accounted for the association between early onset marijuana use and delayed recall. No amnestic effect of marijuana use was observed. (PsycINFO Database Record
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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.