The University of Southampton
University of Southampton Institutional Repository

Cognitive and subjective dose response effects of acute oral Delta 9-tetrahydrocannabinol (THC) in infrequent cannabis users

Cognitive and subjective dose response effects of acute oral Delta 9-tetrahydrocannabinol (THC) in infrequent cannabis users
Cognitive and subjective dose response effects of acute oral Delta 9-tetrahydrocannabinol (THC) in infrequent cannabis users
Rationale. Although some aspects of memory functions are known to be acutely impaired by (9-tetrahydrocannabinol ((9-THC; the main active constituent of marijuana), effects on other aspects of memory are not known and the time course of functional impairments is unclear.
Objective. The present study aimed to detail the acute and residual cognitive effects of (9-THC in infrequent cannabis users.
Methods. A balanced, double-blind cross-over design was used to compare the effects of 7.5 mg and 15 mg (9-THC with matched placebo in 15 male volunteers. Participants were assessed pre and 1, 2, 4, 6, 8, 24 and 48 h post-drug.
Results. (9-THC 15 mg impaired performance on two explicit memory tasks at the time of peak plasma concentration (2 h post-drug). At the same time point, performance on an implicit memory task was preserved intact. The higher dose of (9-THC resulted in no learning whatsoever occurring over a three-trial selective reminding task at 2 h. Working memory was generally unaffected by (9-THC. In several tasks, (9-THC increased both speed and error rates, reflecting "riskier" speed-accuracy trade-offs. Subjective effects were also most marked at 2 h but often persisted longer, with participants rating themselves as "stoned" for 8 h. Participants experienced a strong drug effect, liked this effect and, until 4 h, wanted more oral (9-THC. No effects of (9-THC were found 24 or 48 h following ingestion indicating that the residual effects of oral (9-THC are minimal.
Conclusions. These data demonstrate that oral (9-THC impairs episodic memory and learning in a dose-dependent manner whilst sparing perceptual priming and working memory.
cannabis, marijuana, thc, memory, priming, subjective effects
0033-3158
61-70
Curran, Valerie H.
3185d233-ccaa-46e9-9916-3de1a4dc25d8
Brignell, Catherine
ec44ecae-8687-4bbb-bc81-8c2c8f27febd
Fletcher, Sally
bac5769f-8c30-4109-a783-ac6343831f1e
Middleton, Paul
05b9d158-597f-4a1d-8fb6-2f241e6db9e5
Henry, John
70669204-8089-45b8-9f89-781c13be5f17
Curran, Valerie H.
3185d233-ccaa-46e9-9916-3de1a4dc25d8
Brignell, Catherine
ec44ecae-8687-4bbb-bc81-8c2c8f27febd
Fletcher, Sally
bac5769f-8c30-4109-a783-ac6343831f1e
Middleton, Paul
05b9d158-597f-4a1d-8fb6-2f241e6db9e5
Henry, John
70669204-8089-45b8-9f89-781c13be5f17

Curran, Valerie H., Brignell, Catherine, Fletcher, Sally, Middleton, Paul and Henry, John (2002) Cognitive and subjective dose response effects of acute oral Delta 9-tetrahydrocannabinol (THC) in infrequent cannabis users. Psychopharmacology, 164 (1), 61-70. (doi:10.1007/s00213-002-1169-0).

Record type: Article

Abstract

Rationale. Although some aspects of memory functions are known to be acutely impaired by (9-tetrahydrocannabinol ((9-THC; the main active constituent of marijuana), effects on other aspects of memory are not known and the time course of functional impairments is unclear.
Objective. The present study aimed to detail the acute and residual cognitive effects of (9-THC in infrequent cannabis users.
Methods. A balanced, double-blind cross-over design was used to compare the effects of 7.5 mg and 15 mg (9-THC with matched placebo in 15 male volunteers. Participants were assessed pre and 1, 2, 4, 6, 8, 24 and 48 h post-drug.
Results. (9-THC 15 mg impaired performance on two explicit memory tasks at the time of peak plasma concentration (2 h post-drug). At the same time point, performance on an implicit memory task was preserved intact. The higher dose of (9-THC resulted in no learning whatsoever occurring over a three-trial selective reminding task at 2 h. Working memory was generally unaffected by (9-THC. In several tasks, (9-THC increased both speed and error rates, reflecting "riskier" speed-accuracy trade-offs. Subjective effects were also most marked at 2 h but often persisted longer, with participants rating themselves as "stoned" for 8 h. Participants experienced a strong drug effect, liked this effect and, until 4 h, wanted more oral (9-THC. No effects of (9-THC were found 24 or 48 h following ingestion indicating that the residual effects of oral (9-THC are minimal.
Conclusions. These data demonstrate that oral (9-THC impairs episodic memory and learning in a dose-dependent manner whilst sparing perceptual priming and working memory.

This record has no associated files available for download.

More information

Published date: 2002
Keywords: cannabis, marijuana, thc, memory, priming, subjective effects

Identifiers

Local EPrints ID: 46254
URI: http://eprints.soton.ac.uk/id/eprint/46254
ISSN: 0033-3158
PURE UUID: 92c33ced-5e1e-46e1-813a-126e24193086
ORCID for Catherine Brignell: ORCID iD orcid.org/0000-0001-7768-6272

Catalogue record

Date deposited: 08 Jun 2007
Last modified: 16 Mar 2024 03:42

Export record

Altmetrics

Contributors

Author: Valerie H. Curran
Author: Sally Fletcher
Author: Paul Middleton
Author: John Henry

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×