Sensory, perceptual, motor and cognitive functioning and subjective reports following oral administration of delta9-tetrahydrocannabinol.
B A Peters, E G Lewis, R E Dustman, R C Straight, E C Beck
Psychopharmacologia May 28, 1976 DOI: 10.1007/bf00735812 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Peer reviewed |
|---|---|
| Sample size | 20 |
| Population | 10 frequent and 10 occasional marijuana users |
| Interventions | delta9-tetrahydrocannabinol (THC) placebo |
| Dose | 0.2, 0.4, and 0.6 mg/kg |
| Measures | Subjective Drug Effects Questionnaire |
| Topics | Cannabis |
| Key findings | Oral THC at 0.2, 0.4, and 0.6 mg/kg had minimal effects on individual objective test scores but a small, consistent detrimental effect on overall proficiency and variability when scores were combined. Subjective effects on mood, feeling, perception, and somatic sensations were pronounced in all subjects and stronger in occasional users. The authors proposed that marijuana's main effects act on the autonomic nervous system rather than higher cortical functions. |
Abstract
Three dose levels, 0.2, 0.4, and 0.6 mg/kg, of delta9-tetrahydrocannabinol (THC) and a placebo were orally administered to 10 frequent and 10 occasional marijuana users. Following ingestion of each dose and the placebo, objective tests selected from a battery of sensory and perceptual motor tests routinely used to evaluate cerebral dysfunction in hospitalized patients were administered. The influence of delta9-THC on proficiency and variability of performance was minimal. However, when individual test scores and variabilities were combined and converted to standard scores, allowing for analysis of overall performance, THC had a small but consistent detrimental effect on both proficiency and variability of performance. In contrast, THC exerted profound effects on the subjective experiences of the volunteers as assessed by the Subjective Drug Effects Questionnaire. Subjective changes in mood, feeling, perception and somatic sensations were reported by all subjects but were more pronounced in the occasional user group. It was proposed that the small impairment noted in objective test performance after ingestion of delta9-THC as contrasted to the large effects on subjective responses suggests that the principal effects of marijuana are on the autonomic nervous system rather than on higher cortical functions.