Cannabis use and neurocognitive functioning in a non-clinical sample of users.

26 de fevereiro de 20143min0

Addict Behav. 2014 Feb 6. pii: S0306-4603(14)00020-3. doi: 10.1016/j.addbeh.2014.01.019. [Epub ahead of print]

Cannabis use and neurocognitive functioning in a non-clinical sample of users.

Thames AD1, Arbid N2, Sayegh P3.

Author information



With the recent debates over marijuana legalization and increases in use, it is critical to examine its role in cognition. While many studies generally support the adverse acute effects of cannabis on neurocognition, the non-acute effects remain less clear. The current study used a cross-sectional design to examine relationships between recent and past cannabis use on neurocognitive functioning in a non-clinical adult sample.


One hundred and fifty-eight participants were recruited through fliers distributed around local college campuses and the community. All participants completed the Brief Drug Use History Form, the Structured Clinical Interview for DSM-IV Disorders, and neurocognitive assessment, and underwent urine toxicology screening. Participants consisted of recent users (n=68), past users (n=41), and non-users (n=49).


Recent users demonstrated significantly (p<.05) worse performance than non-users across cognitive domains of attention/working memory (M=42.4, SD=16.1 vs. M=50.5, SD=10.2), information processing speed (M=44.3, SD=7.3 vs. M=52.1, SD=11.0), and executive functioning (M=43.6, SD=13.4 vs. M=48.6, SD=7.2). There were no statistically significant differences between recent users and past users on neurocognitive performance. Frequency of cannabis use in the last 4weeks was negatively associated with global neurocognitive performance and all individual cognitive domains. Similarly, amount of daily cannabis use was negatively associated with global neurocognitive performance and individual cognitive domains.


Our results support the widespread adverse effects of cannabis use on neurocognitive functioning. Although some of these adverse effects appear to attenuate with abstinence, past users’ neurocognitive functioning was consistently lower than non-users.

Copyright © 2014 Elsevier Ltd. All rights reserved.


Abstinence, Abuse, Cannabis, Cognition, Past use, Premorbid IQ



[PubMed – as supplied by publisher]

Sobre a UNIAD

A Unidade de Pesquisa em álcool e Drogas (UNIAD) foi fundada em 1994 pelo Prof. Dr. Ronaldo Laranjeira e John Dunn, recém-chegados da Inglaterra. A criação contou, na época, com o apoio do Departamento de Psiquiatria da UNIFESP. Inicialmente (1994-1996) funcionou dentro do Complexo Hospital São Paulo, com o objetivo de atender funcionários dependentes.


    Skip to content