Measuring acute effects of subanesthetic ketamine on cerebrovascular hemodynamics in humans using TD-fNIRS.
Adelaida Castillo, Julien Dubois, Ryan M. Field, Frank A. Fishburn, Andrew Gundran, Wilson C. Ho, Sami Jawhar, Julian Kates-Harbeck, Zahra M. Aghajan, Naomi Miller, Katherine L. Perdue, Jake Phillips, Wesley C Ryan, Mahdi Shafiei, Felix Scholkmann, Moriah Taylor
Scientific Reports July 19, 2023 DOI: 10.1038/s41598-023-38258-8 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Single-blind, placebo-controlled study with a non-randomized design Peer reviewed |
|---|---|
| Sample size | 15 |
| Population | Healthy participants (8 females, 7 males, age 32.4 ± 7.5 years) |
| Interventions | Ketamine Placebo (saline) |
| Dose | 0.75 mg/kg |
| Topics | Esketamine Ketamine |
| Citations | 19 |
| Key points | Ketamine caused a brain-wide reduction in fractional amplitude of low frequency fluctuations and decreased global brain connectivity in the prefrontal region, along with altered consciousness and physiological changes. |
Abstract
Quantifying neural activity in natural conditions (i.e. conditions comparable to the standard clinical patient experience) during the administration of psychedelics may further our scientific understanding of the effects and mechanisms of action. This data may facilitate the discovery of novel biomarkers enabling more personalized treatments and improved patient outcomes. In this single-blind, placebo-controlled study with a non-randomized design, we use time-domain functional near-infrared spectroscopy (TD-fNIRS) to measure acute brain dynamics after intramuscular subanesthetic ketamine (0.75 mg/kg) and placebo (saline) administration in healthy participants (n = 15, 8 females, 7 males, age 32.4 ± 7.5 years) in a clinical setting. We found that the ketamine administration caused an altered state of consciousness and changes in systemic physiology (e.g. increase in pulse rate and electrodermal activity). Furthermore, ketamine led to a brain-wide reduction in the fractional amplitude of low frequency fluctuations, and a decrease in the global brain connectivity of the prefrontal region. Lastly, we provide preliminary evidence that a combination of neural and physiological metrics may serve as predictors of subjective mystical experiences and reductions in depressive symptomatology. Overall, our study demonstrated the successful application of fNIRS neuroimaging to study the physiological effects of the psychoactive substance ketamine in humans, and can be regarded as an important step toward larger scale clinical fNIRS studies that can quantify the impact of psychedelics on the brain in standard clinical settings.
Comparable studies
Other non-randomized and open-label trials on ketamine, most cited first.
Citations in the library
Cited by 5
- Effects of a dissociative drug on fronto-limbic resting-state functional connectivity in individuals with posttraumatic stress disorder: a randomized controlled pilot study. Psychopharmacology October 23, 2023
- Effect of Acute Ketamine Treatment on Sympathetic Regulation Indexed by Electrodermal Activity in Adolescent Major Depression. Pharmaceuticals March 10, 2024
- Ketamine-Occasioned Mystical Experience in Veterans with Treatment-Resistant Depression: A Retrospective Exploratory Analysis. Psychedelic Medicine August 1, 2025
- Clinical Predictors of Antidepressant Effects of Ketamine and Esketamine in Treatment-Resistant Unipolar and Bipolar Depression: A Systematic Review CNS Drugs July 1, 2026
- Detecting neuroplastic effects induced by ketamine in healthy human subjects: A multimodal approach. Journal of Cerebral Blood Flow & Metabolism March 21, 2026
Cites 35
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- Factor Analysis of the Mystical Experience Questionnaire: A Study of Experiences Occasioned by the Hallucinogen Psilocybin Journal for the Scientific Study of Religion December 1, 2012
and 30 more in the library