The residual neuropsychological effects of cannabis: the current status of research.

@article{Pope1995TheRN,
  title={The residual neuropsychological effects of cannabis: the current status of research.},
  author={Harrison G. Pope and Amanda J. Gruber and Deborah A. Yurgelun-Todd},
  journal={Drug and alcohol dependence},
  year={1995},
  volume={38 1},
  pages={
          25-34
        }
}

Residual neuropsychologic effects of cannabis

It appears safe to conclude that deficits in attention and memory persist for at least several days after discontinuing regular heavy cannabis use, and it seems likely that such long-term effects, if they exist, are subtle and not clinically disabling—at least in the majority of cases.

Non-acute (residual) neurocognitive effects of cannabis use: A meta-analytic study

The results indicate that there might be decrements in the ability to learn and remember new information in chronic users, whereas other cognitive abilities are unaffected, and the small magnitude of these effect sizes suggests that if cannabis compounds are found to have therapeutic value, they may have an acceptable margin of safety under the more limited conditions of exposure that would likely obtain in a medical setting.

Residual effects of cannabis use on neurocognitive performance after prolonged abstinence: a meta-analysis.

Overall, these meta-analyses demonstrate that any negative residual effects on neurocognitive performance attributable to either cannabis residue or withdrawal symptoms are limited to the first 25 days of abstinence and there was no evidence for enduring negative effects of cannabis use.

Nonacute (Residual) Neuropsychological Effects of Cannabis Use: A Qualitative Analysis and Systematic Review

From the 40 articles that met criteria for inclusion in this review, the authors could not detect consistent evidence for persisting neuropsychological deficits in cannabis users; however, 22 of the 40 studies reported at least some subtle impairments.

Chronic cognitive impairment in users of 'ecstasy' and cannabis.

  • A. KlugmanJ. Gruzelier
  • Psychology, Biology
    World psychiatry : official journal of the World Psychiatric Association
  • 2003
It would appear that MDMA does indeed have subtle long-term effects on complex memory and executive functions that are independent of cannabis and may remain with abstention, consistent with evidence of disruption of the serotonin system in animal and human studies.

Acute and Non-acute Effects of Cannabis on Brain Functioning and Neuropsychological Performance

  • R. Gonzalez
  • Psychology, Biology
    Neuropsychology Review
  • 2007
The scientific literature on cannabis use, neuropsychological deficits and differences in brain functioning, and the dire impact of drug addiction on a person’s life and everyday functioning are reviewed, providing evidence for converging findings, and highlighting areas in need of further investigation.

Weighing the Evidence: A Systematic Review on Long-Term Neurocognitive Effects of Cannabis Use in Abstinent Adolescents and Adults

Findings are mixed regarding impairments in inhibition, impulsivity and decision making for CU, but there is a trend towards worse performance, and heavy use is found to be more consistently associated with effects in diverse domains than early age of onset.

Cognitive deficits and cognitive normality in recreational cannabis and Ecstasy/MDMA users

  • A. Parrott
  • Psychology, Biology
    Human psychopharmacology
  • 2003
The understanding of the long-term effects of cannabis is based upon an extensive empirical literature, describing a mixture of significant and non-significant findings.

Clinical Implications and Methodological Challenges in the Study of the Neuropsychological Correlates of Cannabis, Stimulant, and Opioid Abuse

The aim of this review is to summarize the main neuropsychological impairments shown by classic studies, as well as these new discoveries in executive functioning and highlight the convenience of intervening in those functions most relevant to the abusers' persistence in consumption and risk of relapse.

Subjective Effects of Cannabis Before the First Psychotic Episode

The results suggest that schizophrenia patients in the prodromal phase and subjects at UHR for psychosis are more sensitive to some negative effects of cannabis, in particular psychotic effects, compared to cannabis users from the general population.
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