Effects of Different Subanesthetic Doses of (S)-Ketamine on Neuropsychology, Psychopathology, and State of Consciousness in Man
Torsten Passie, Matthias Karst, Birgitt Wiese, Hinderk M. Emrich, Udo Schneider
Neuropsychobiology 2005 DOI: 10.1159/000085724 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized placebo-controlled trial Peer reviewed |
|---|---|
| Sample size | 12 |
| Population | Healthy male volunteers |
| Intervention | (S)-ketamine |
| Dose | low dose/high dose |
| Topics | Ketamine Esketamine |
| Keywords | Neuropsychology Psychopathology Schizophrenia object-oriented programming Placebo Antagonist Clinical psychology Anesthesia Cognition |
| Citations | 35 |
| Key findings | Subanaesthetic doses of (S)-ketamine produce significant, dose-dependent impairment in divided and sustained attention and psychopathology, but not in most other neuropsychological tasks. |
Abstract
This is the first neuropsychological study using the S-enantiomer of the noncompetitive N-methyl-D-aspartate antagonist ketamine. In 2 randomized placebo-controlled trials we studied effects of two different doses of (S)-ketamine (low dose/high dose) on neuropsychological functions and psychopathology in 12 healthy male volunteers. Impairment was measured via standardized neuropsychological tests. Results indicate that both subanaesthetic doses produce only nonsignificant impairment in most of the tasks. Tasks involving divided and sustained attention as well as scores for objective and subjective psychopathology show significant impairment in a dose-dependent manner. Implications of these findings for the neuropsychology of attention and schizophrenia are discussed.
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
- A qualitative and quantitative account of patient's experiences of ketamine and its antidepressant properties. Journal of Psychopharmacology August 1, 2021
- Ketamine-Enhanced Psychotherapy: Preliminary Clinical Observations on its Effects in Treating Death Anxiety International Journal of Transpersonal Studies 2007
- Ketamine Enhanced Psychotherapy: Preliminary Clinical Observations on Its Effectiveness in Treating Alcoholism. The Humanistic Psychologist 2006
- The Altered States Database: Psychometric data from a systematic literature review. Scientific Data November 23, 2022
- Update of the Altered States Database (ASDB): 2022-12-31 February 22, 2023
and 7 more in the library
Cites 14
- 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
- The Standardized Psychometric Assessment of Altered States of Consciousness (ASCs) in Humans Pharmacopsychiatry July 1, 1998
- Psychedelic Effects of Ketamine in Healthy Volunteers Anesthesiology 1998
- NMDA receptor regulation of memory and behavior in humans Hippocampus October 1, 2001
and 9 more in the library