Acute effects of marijuana on cognition: relationships to chronic effects and smoking techniques.
R I Block, R Farinpour, K Braverman
Pharmacology, Biochemistry, and Behavior November 1992 DOI: 10.1016/0091-3057(92)90424-e (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Placebo-controlled Double-blind Peer reviewed |
|---|---|
| Sample size | 48 |
| Population | Adult male volunteers |
| Interventions | Marijuana placebo |
| Duration | Eight test sessions |
| Topics | Cannabis |
| Key findings | Marijuana impaired all tested cognitive capabilities except abstraction and vocabulary, with effects more pervasive than those previously associated with heavy chronic use on the same tests. It also encouraged more uncommon associations and impaired word-pair learning depending on associative relationships between words. Prolonged breath holding did not generally increase marijuana's effects but itself affected performance on four tests. |
Abstract
A double-blind, placebo-controlled study assessed acute effects on human cognition of marijuana smoking involving long or short durations of inhalation and breath holding. During eight test sessions, 48 adult, male volunteers completed standardized, pencil-and-paper tests of educational development and ability, as well as computerized tests of learning, associative processes, abstraction, and psychomotor performance. Marijuana impaired all capabilities except abstraction and vocabulary. These impairments were more pervasive than those associated with heavy, chronic marijuana use in a previous study involving the same tests, but showed some similarities. Marijuana altered associative processes, encouraging more uncommon associations. Marijuana-induced impairment in learning pairs of words was influenced by associative relationships between the words. There were a few hints that prolonged breath holding increased marijuana's effects under some test conditions, but in general it did not. Prolonged breath holding itself affected performance in four tests, regardless of whether subjects smoked marijuana or placebo. Whether physiological or psychological factors (e.g., exposure to carbon monoxide in smoke or subjects' expectations) produced these effects could not be determined.
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 15
- Investigating the interaction between schizotypy, divergent thinking and cannabis use Consciousness and Cognition January 10, 2012
- Cognitive motor deficits in cannabis users Current Opinion in Behavioral Sciences July 19, 2016
- Consommation de cannabis: quels sont les risques ? Annales de Toxicologie Analytique 2008
- Acute effects of partial CB1 receptor agonists on cognition - A meta-analysis of human studies. Progress in Neuro-Psychopharmacology and Biological Psychiatry August 10, 2020
- [Dependence and Cytotoxicity of Components of Cannabis]. Yakugaku Zasshi 2020
and 10 more in the library