Therapeutic doses of ketamine acutely attenuate the aversive effect of losses during decision-making.
Mariann Oemisch, Hyojung Seo
Elife May 3, 2024 DOI: 10.7554/elife.87529 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study with computational modeling Peer reviewed |
|---|---|
| Population | Rhesus macaques |
| Intervention | Ketamine |
| Dose | therapeutic doses |
| Topics | Esketamine Ketamine |
| Keywords | Nmda receptor Affective memory Negative valence Reinforcement learning Rhesus macaque Antidepressants Animal-studies Depression-treatment Behavioral-neuroscience |
| Key findings | Ketamine reduces the aversiveness of undesirable outcomes (losses) without affecting gain evaluation, motivation, or other cognitive aspects of learning, and this effect is separable from side effects like fixation errors. |
Abstract
The discovery of rapid-acting antidepressant, ketamine has opened a pathway to a new generation of treatments for depression, and inspired neuroscientific investigation based on a new perspective that non-adaptive changes in the intrinsic excitatory and inhibitory circuitry might underlie the pathophysiology of depression. Nevertheless, it still remains largely unknown how the hypothesized molecular and synaptic levels of changes in the circuitry might mediate behavioral and neuropsychological changes underlying depression, and how ketamine might restore adaptive behavior. Here, we used computational models to analyze behavioral changes induced by therapeutic doses of ketamine, while rhesus macaques were iteratively making decisions based on gains and losses of tokens. When administered intramuscularly or intranasally, ketamine reduced the aversiveness of undesirable outcomes such as losses of tokens without significantly affecting the evaluation of gains, behavioral perseveration, motivation, and other cognitive aspects of learning such as temporal credit assignment and time scales of choice and outcome memory. Ketamine's potentially antidepressant effect was separable from other side effects such as fixation errors, which unlike outcome evaluation, was readily countered with strong motivation to avoid errors. We discuss how the acute effect of ketamine to reduce the initial impact of negative events could potentially mediate longer-term antidepressant effects through mitigating the cumulative effect of those events produced by slowly decaying memory, and how the disruption-resistant affective memory might pose challenges in treating depression. Our study also invites future investigations on ketamine's antidepressant action over diverse mood states and with affective events exerting their impacts at diverse time scales.
Comparable studies
Other preclinical and animal studies on ketamine, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| mTOR-Dependent Synapse Formation Underlies the Rapid Antidepressant Effects of NMDA Antagonists Rats | 2010 | Observational study | |
| Activation of Glutamatergic Neurotransmission by Ketamine: A Novel Step in the Pathway from NMDA Receptor Blockade to Dopaminergic and Cognitive Disruptions Associated with the Prefrontal Cortex Conscious rats | 1997 | Dose-response study with microdialysis and behavioral testing | |
| NMDAR inhibition-independent antidepressant actions of ketamine metabolites Mice | 2016 | Preclinical study | |
| The dissociative anaesthetics, ketamine and phencyclidine, selectively reduce excitation of central mammalian neurones by N‐methyl‐aspartate Spinal neurons in decerebrate or pentobarbitone-anaesthetized cats and rats | 1983 | Experimental study | |
| R-ketamine: a rapid-onset and sustained antidepressant without psychotomimetic side effects Mice | 2015 | Experimental study |
Citations in the library
Cites 12
- A Randomized Trial of an N-methyl-D-aspartate Antagonist in Treatment-Resistant Major Depression Archives of General Psychiatry August 1, 2006
- Subanesthetic Effects of the Noncompetitive NMDA Antagonist, Ketamine, in Humans Archives of General Psychiatry March 1, 1994
- mTOR-Dependent Synapse Formation Underlies the Rapid Antidepressant Effects of NMDA Antagonists Science August 19, 2010
- A Consensus Statement on the Use of Ketamine in the Treatment of Mood Disorders JAMA Psychiatry March 1, 2017
- Side-effects associated with ketamine use in depression: a systematic review. The Lancet Psychiatry 2018
and 7 more in the library