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Cited by 195Cannabis and Cannabinoid ResearchForensic Toxicology and Drug AnalysisSchizophrenia research and treatment

The DOI matches its Crossref record; 36 of the 36 references it cites were found in a registry or an index.

Sub-chronic impact of cannabinoids in street cannabis on cognition, psychotic-like symptoms and psychological well-being

Morgan, C. J. A., Gardener, C., Schafer, G., Swan, S., Demarchi, C., Freeman, T. P., Warrington, P., Rupasinghe, I., Ramoutar, A., Tan, N., Wingham, G., Lewis, S., Curran, H. V.·2012·Psychological Medicine
DOI 10.1017/s0033291711001322
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Abstract

BACKGROUND: Cannabis varies considerably in levels of its two major constituent cannabinoids - (delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Recently, we found evidence that those who smoked cannabis containing detectable levels of CBD had fewer psychotic-like symptoms than those whose cannabis had no CBD. The present study aimed, first, to replicate those findings and, second, to determine whether protective effects of CBD may extend to other harms of cannabis, such as memory impairment and reduced psychological well-being. METHOD: A total of 120 current cannabis smokers, 66 daily users and 54 recreational users were classified into groups according to whether analysis of their hair revealed the presence or absence of CBD and high versus low levels of THC. All were assessed on measures of psychosis-like symptoms, memory (prose recall; source memory) and depression/anxiety. RESULTS: Lower psychosis-like symptoms were found in those whose hair had CBD compared with those without. However, this was seen only in recreational users, who had higher levels of THC in their hair. Higher THC levels in hair were associated with increased depression and anxiety. Prose recall and source memory were poorer in daily users with high THC levels in hair while recognition memory was better in individuals with CBD present in hair. CONCLUSIONS: CBD attenuates the psychotic-like effects of cannabis over time in recreational users. Higher THC negatively impacts on memory and psychological well-being. These findings raise concerns for the harms stemming from use of varieties such as 'skunk' (sensimillia), which lack any CBD but currently dominate the supply of cannabis in many countries.

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Crossref · 10.1017/s0033291711001322

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Research works printed but not linked: 3

  1. Spielberger, 1983, State-Trait Anxiety Inventory (Form Ys)
  2. Hardwick, 2008, Home Office Cannabis Potency Study
  3. 2009, World Drug Report 2009

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Metadata

Authors
Morgan, C. J. A., Gardener, C., Schafer, G., Swan, S., Demarchi, C., Freeman, T. P., Warrington, P., Rupasinghe, I., Ramoutar, A., Tan, N., Wingham, G., Lewis, S., & Curran, H. V.
Affiliations
University College London (GB)
Corresponding author
Morgan, C. J. A.
ORCID
Venue
Psychological Medicine
Publisher
Cambridge University Press (CUP)
Published
2011-07-29
Volume
42
Issue
2
Pages
391-400
ISSN
  • 0033-2917 (ISSN-L)
  • 1469-8978
DOI
10.1017/s0033291711001322
OpenAlex
W2108405197
Cited by
195
References
36
Citations by year
2026: 4 · 2025: 6 · 2024: 5 · 2023: 13 · 2022: 14 · 2021: 21 · 2020: 20 · 2019: 17 · 2018: 16 · 2017: 18 · 2016: 14 · 2015: 19 · 2014: 9 · 2013: 11 · 2012: 8
FWCI
6.56
Type
journal article
Language
en
Open access
closed
Licence
www.cambridge.org/core/terms (unspecified)
Locations
  • Psychological Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • Research Bank (Australian Catholic University) (submittedVersion)
  • UCL Discovery (University College London) (submittedVersion)
  • Research Portal (King's College London) (submittedVersion)
  • Research Explorer (The University of Manchester) (submittedVersion)
Funders
Medical Research Council
Topics
  • Health Sciences › Medicine › Pharmacology (medical) › Cannabis and Cannabinoid Research
  • Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Toxicology › Forensic Toxicology and Drug Analysis
  • Health Sciences › Medicine › Psychiatry and Mental health › Schizophrenia research and treatment
Keywords
cannabinoids, cannabidiol, delta-9-tetrahydrocannabinol, psychotic-like symptoms, memory impairment, source memory, prose recall, depression, anxiety, psychological well-being, hair analysis
MeSH terms
Adolescent, Adult, Anxiety, Cannabidiol, Cognition Disorders, Depression, Female, Hair, Humans, Male, Marijuana Smoking, Memory, Psychoses, Substance-Induced, Schizotypal Personality Disorder, Illicit Drugs, Dronabinol, Young Adult

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