Effects of acute smoked marijuana on complex cognitive performance.
Carl L. Hart, W Van Gorp, Margaret Haney, Richard W Foltin, Marian W Fischman
Neuropsychopharmacology November 2001 DOI: 10.1016/s0893-133x(01)00273-1 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Within-participant double-blind experimental study Peer reviewed |
|---|---|
| Sample size | 18 |
| Population | Healthy experienced marijuana smokers (8 females, 10 males) averaging 24 marijuana cigarettes per week |
| Dose | 0%, 1.8%, or 3.9% Delta(9)-THC w/w |
| Duration | Three sessions separated by at least 72 hours |
| Measures | computerized cognitive tasks (not specified by name), blood pressure, heart rate, subjective effects ratings |
| Topics | Cannabis |
| Key findings | Acute marijuana smoking increased premature responses and task completion times but had no effect on accuracy in measures of cognitive flexibility, mental calculation, and reasoning. Heart rate and subjective effects increased in a Delta(9)-THC concentration-dependent manner, indicating minimal effects on complex cognitive performance in experienced users. |
Abstract
Although the ability to perform complex cognitive operations is assumed to be impaired following acute marijuana smoking, complex cognitive performance after acute marijuana use has not been adequately assessed under experimental conditions. In the present study, we used a within-participant double-blind design to evaluate the effects acute marijuana smoking on complex cognitive performance in experienced marijuana smokers. Eighteen healthy research volunteers (8 females, 10 males), averaging 24 marijuana cigarettes per week, completed this three-session outpatient study; sessions were separated by at least 72-hrs. During sessions, participants completed baseline computerized cognitive tasks, smoked a single marijuana cigarette (0%, 1.8%, or 3.9% Delta(9)-THC w/w), and completed additional cognitive tasks. Blood pressure, heart rate, and subjective effects were also assessed throughout sessions. Marijuana cigarettes were administered in a double-blind fashion and the sequence of Delta(9)-THC concentration order was balanced across participants. Although marijuana significantly increased the number of premature responses and the time participants required to complete several tasks, it had no effect on accuracy on measures of cognitive flexibility, mental calculation, and reasoning. Additionally, heart rate and several subjective-effect ratings (e.g., "Good Drug Effect," "High," "Mellow") were significantly increased in a Delta(9)-THC concentration-dependent manner. These data demonstrate that acute marijuana smoking produced minimal effects on complex cognitive task performance in experienced marijuana users.
Comparable studies
Other randomized controlled trials on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Cannabidiol inhibits THC-elicited paranoid symptoms and hippocampal-dependent memory impairment Healthy participants | 2012 | Randomized controlled trial | n = 48 |
| Distinct Effects of Δ9-Tetrahydrocannabinol and Cannabidiol on Neural Activation During Emotional Processing Healthy, English-native, right-handed men who had used cannabis 15 times or less in... | 2009 | Double-blind, randomized, placebo-controlled crossover trial | n = 15 |
| Acute Effects of a Single, Oral dose of d9-tetrahydrocannabinol (THC) and Cannabidiol (CBD) Administration in Healthy Volunteers Healthy male subjects | 2012 | Randomized controlled trial | n = 16 |
| Modulation of Mediotemporal and Ventrostriatal Function in Humans by Δ9-Tetrahydrocannabinol Healthy, native English-speaking, right-handed men of white race/ethnicity who had used... | 2009 | Randomized controlled trial | n = 15 |
| Cannabidiol (CBD) content in vaporized cannabis does not prevent tetrahydrocannabinol (THC)-induced impairment of driving and cognition Healthy volunteers with a history of light cannabis use | 2019 | Randomized, double-blind, within-subjects crossover | n = 14 |
Citations in the library
Cited by 61
- Gone to Pot – A Review of the Association between Cannabis and Psychosis Frontiers in Psychiatry May 22, 2014
- Tolerance and cross-tolerance to neurocognitive effects of THC and alcohol in heavy cannabis users Psychopharmacology October 30, 2010
- Smoked Cannabis' Psychomotor and Neurocognitive Effects in Occasional and Frequent Smokers Journal of Analytical Toxicology March 4, 2015
- Human Laboratory Studies on Cannabinoids and Psychosis. Biological Psychiatry April 1, 2016
- Effects of Cannabis on Impulsivity: A Systematic Review of Neuroimaging Findings Current Pharmaceutical Design May 10, 2014
and 56 more in the library
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