Topological Analysis of Differential Effects of Ketamine and Propofol Anesthesia on Brain Dynamics
Thomas F. Varley, Vanessa Denny, Olaf Sporns, Alice Patania
bioRxiv Preprint Server April 4, 2020 preprint DOI: 10.1101/2020.04.04.025437 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental neuroscience |
|---|---|
| Sample size | 2 |
| Population | Macaques |
| Interventions | propofol ketamine |
| Topics | Altered states of consciousness Ketamine Esketamine |
| Keywords | Awareness Sentience Perception Mind Unconsciousness Brain dynamics Brain activity Neural activity Brain states Brain patterns Neural dynamics Brain function Neurophysiology Anesthetics Propofol Sedatives Hypnotics Anesthesia drugs Pharmacological agents Neuroscience research Brain research Neural research Cognitive neuroscience Experimental neuroscience Macaque study |
| Citations | 6 |
| Key findings | The awake condition exhibited the richest brain dynamics, propofol produced the most impoverished dynamics, and ketamine showed intermediate complexity between the two. |
Abstract
Research has found that the vividness of conscious experience is related to brain dynamics. Despite both being anesthetics, propofol and ketamine produce different subjective states: we explore the different effects of these two anaesthetics on the structure of dynamic attractors reconstructed from electrophysiological activity recorded from cerebral cortex of two macaques. We used two methods: the first embeds the recordings in a continuous high-dimensional manifold on which we use topological data analysis to infer the presence of higher-order dynamics. The second reconstruction, an ordinal partition network embedding, allows us to create a discrete state-transition network, which is amenable to information-theoretic analysis and contains rich information about state-transition dynamics. We find that the awake condition generally had the “richest” structure, visiting the most states, the presence of pronounced higher-order structures, and the least deterministic dynamics. In contrast, the propofol condition had the most dissimilar dynamics, transitioning to a more impoverished, constrained, low-structure regime. The ketamine condition, interestingly, seemed to combine aspects of both: while it was generally less complex than the awake condition, it remained well above propofol in almost all measures. These results provide provides deeper and more comprehensive insights than what is typically gained by using point-measures of complexity.
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 20
- Subanesthetic Effects of the Noncompetitive NMDA Antagonist, Ketamine, in Humans Archives of General Psychiatry March 1, 1994
- Neural correlates of consciousness: progress and problems Nature Reviews Neuroscience April 20, 2016
- Consciousness as Integrated Information: a Provisional Manifesto Biological Bulletin December 1, 2008
- The entropic brain: a theory of conscious states informed by neuroimaging research with psychedelic drugs Frontiers in Human Neuroscience 2014
- Ketamine and Ketamine Metabolite Pharmacology: Insights into Therapeutic Mechanisms Pharmacological Reviews June 26, 2018
and 15 more in the library