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 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.
Comparable studies
Other randomized controlled trials on ketamine, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Subanesthetic Effects of the Noncompetitive NMDA Antagonist, Ketamine, in Humans Healthy human subjects recruited from the community | 1994 | Randomized controlled trial | n = 19 |
| Antidepressant Efficacy of Ketamine in Treatment-Resistant Major Depression: A Two-Site Randomized Controlled Trial Patients with treatment-resistant major depression experiencing a major depressive episode | 2013 | Randomized controlled trial | n = 73 |
| Remifentanil-induced Postoperative Hyperalgesia and Its Prevention with Small-dose Ketamine Patients undergoing major abdominal surgery | 2005 | Randomized controlled trial | n = 75 |
| Efficacy of Intravenous Ketamine for Treatment of Chronic Posttraumatic Stress Disorder Patients with chronic PTSD related to a range of trauma exposures | 2014 | Randomized controlled trial | n = 41 |
| Ketamine-Induced Deficits in Auditory and Visual Context-Dependent Processing in Healthy Volunteers Healthy volunteers | 2000 | Single-blind placebo-controlled study | n = 20 |
Citations in the library
Cited by 12
- Cognitive and subjective acute dose effects of intramuscular ketamine in healthy adults. Experimental and Clinical Psychopharmacology November 1, 2006
- Effects of Subanesthetic Ketamine Administration on Visual and Auditory Event-Related Potentials (ERP) in Humans: A Systematic Review Frontiers in Behavioral Neuroscience April 16, 2018
- Psychotomimetic effects of PCP, LSD, and Ecstasy: pharmacological models of schizophrenia? Cambridge University Press eBooks February 4, 2010
- Beyond therapeutic potential: a systematic investigation of ketamine misuse in patients with depressive disorders. Discover Mental Health July 1, 2024
- Translational control by ketamine and its implications for comorbid cognitive deficits in depressive disorders Journal of Neurochemistry June 9, 2022
and 7 more in the library
Cites 5
- Subanesthetic Effects of the Noncompetitive NMDA Antagonist, Ketamine, in Humans Archives of General Psychiatry March 1, 1994
- Recent advances in the phencyclidine model of schizophrenia American Journal of Psychiatry October 1, 1991
- Effects of ketamine on sensory perception: evidence for a role of N-methyl-D-aspartate receptors. Journal of Pharmacology and Experimental Therapeutics March 1, 1992
- Chemical dissociation of human awareness: focus on non-competitive NMDA receptor antagonists. Journal of Psychopharmacology January 1992
- Pharmacologic effects of CI‐581, a new dissociative anesthetic, in man Clinical Pharmacology & Therapeutics May 1, 1965