The effects of sub-anaesthetic doses of ketamine on memory, cognitive performance and subjective experience in healthy volunteers.
G C Harborne, F L Watson, D T Healy, L Groves
Journal of psychopharmacology (Oxford, England) January 1996 DOI: 10.1177/026988119601000208 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Double-blind, Latin square crossover experiment Peer reviewed |
|---|---|
| Sample size | 12 |
| Population | Healthy volunteers |
| Interventions | Ketamine Saline placebo |
| Dose | 25 mg ketamine, 10 mg ketamine, saline placebo, i.m. |
| Duration | Test battery administered over 45 min |
| Topics | Esketamine Ketamine |
| Key findings | Ketamine at 25 mg significantly impaired verbal learning and memory, parallel visual search, some psychomotor measures, arousal, subjective mood, and visual perception, while attention and frontal lobe functioning were relatively unaffected. The authors argue that these selective, dose-related effects on memory and perceptual processes may help explain ketamine's unique subjective state. |
Abstract
The cognitive and subjective effects of sub-anaesthetic doses of ketamine on healthy volunteers were examined. Twelve healthy volunteers received 25 mg ketamine, 10 mg ketamine and saline placebo, i.m. in a double-blind, Latin square design. A cognitive, perceptual and self-report test battery was administered over 45 min. The order of tests was rotated to control for timing effects. Ketamine (25 mg) significantly affected verbal learning and memory, parallel visual search, some measures of psychomotor performance, measures of arousal, subjective mood ratings and visual perception. Measures of attention and frontal lobe functioning were relatively unaffected. Thus, low doses of ketamine had selective, dose-related effects on memory, perceptual and psychomotor functions. The disruption of memory and perceptual processes may help to explain the unique subjective state induced by ketamine.