Effects of the South American Psychoactive Beverage Ayahuasca on Regional Brain Electrical Activity in Humans: A Functional Neuroimaging Study Using Low-Resolution Electromagnetic Tomography
Jordi Riba, P. Anderer, F Jané, Bernd Saletu, Manel J. Barbanoj
Neuropsychobiology 2004 DOI: 10.1159/000077946 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Peer reviewed |
|---|---|
| Sample size | 18 |
| Population | Human volunteers |
| Intervention | Ayahuasca |
| Dose | 0.85 mg DMT/kg body weight |
| Duration | 90 minutes post-dosing |
| Measures | Hallucinogen Rating Scale (HRS), LORETA power |
| Topics | Ayahuasca |
| Keywords | Hallucinogen Electroencephalography Neuroimaging Pharmacology |
| Citations | 131 |
| Key findings | Ayahuasca decreased power density in alpha-2, delta, theta, and beta-1 frequency bands, with regional specificity in temporo-parieto-occipital and temporomedial/frontomedial cortex, alongside increased subjective effects on the Hallucinogen Rating Scale. |
Abstract
Ayahuasca, a South American psychotropic plant tea obtained from Banisteriopsis caapi and Psychotria viridis, combines monoamine oxidase-inhibiting β-carboline alkaloids with N,N-dimethyltryptamine (DMT), a psychedelic agent showing 5-HT2A agonist activity. In a clinical research setting, ayahuasca has demonstrated a combined stimulatory and psychedelic effect profile, as measured by subjective effect self-assessment instruments and dose-dependent changes in spontaneous brain electrical activity, which parallel the time course of subjective effects. In the present study, the spatial distribution of ayahuasca-induced changes in brain electrical activity was investigated by means of low-resolution electromagnetic tomography (LORETA). Electroencephalography recordings were obtained from 18 volunteers after the administration of a dose of encapsulated freeze-dried ayahuasca containing 0.85 mg DMT/kg body weight and placebo. The intracerebral power density distribution was computed with LORETA from spectrally analyzed data, and subjective effects were measured by means of the Hallucinogen Rating Scale (HRS). Statistically significant differences compared to placebo were observed for LORETA power 60 and 90 min after dosing, together with increases in all six scales of the HRS. Ayahuasca decreased power density in the alpha-2, delta, theta and beta-1 frequency bands. Power decreases in the delta, alpha-2 and beta-1 bands were found predominantly over the temporo-parieto-occipital junction, whereas theta power was reduced in the temporomedial cortex and in frontomedial regions. The present results suggest the involvement of unimodal and heteromodal association cortex and limbic structures in the psychological effects elicited by ayahuasca.
Comparable studies
Other randomized controlled trials on ayahuasca, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Rapid antidepressant effects of the psychedelic ayahuasca in treatment-resistant depression: a randomized placebo-controlled trial Patients with treatment-resistant depression | 2018 | Randomized controlled trial | n = 29 |
| Human Pharmacology of Ayahuasca: Subjective and Cardiovascular Effects, Monoamine Metabolite Excretion, and Pharmacokinetics Volunteers with prior experience in the use of psychedelics | 2003 | Double-blind placebo-controlled clinical trial | n = 18 |
| Subjective effects and tolerability of the South American psychoactive beverage Ayahuasca in healthy volunteers Healthy male volunteers with prior experience using ayahuasca | 2001 | Single-blind crossover placebo-controlled clinical trial | n = 6 |
| Increased frontal and paralimbic activation following ayahuasca, the pan-amazonian inebriant Male volunteers with prior experience in the use of psychedelics | 2006 | Randomized controlled trial | n = 15 |
| Human brain effects of DMT assessed via EEG-fMRI. Healthy volunteers | 2023 | Within-subjects, placebo-controlled design | n = 20 |
Citations in the library
Cited by 94
- The Therapeutic Potential of Psychedelic Drugs: Past, Present, and Future. Neuropsychopharmacology April 26, 2017
- Classic psychedelics: An integrative review of epidemiology, therapeutics, mystical experience, and brain network function. Pharmacology & Therapeutics May 1, 2019
- Broadband Cortical Desynchronization Underlies the Human Psychedelic State Journal of Neuroscience September 18, 2013
- Psychiatry & the psychedelic drugs. Past, present & future. Neuropharmacology December 25, 2017
- Classic Hallucinogens and Mystical Experiences: Phenomenology and Neural Correlates. Current Topics in Behavioral Neurosciences 2018
and 89 more in the library
Cites 14
- Dose-Response Study of N,N-Dimethyltryptamine in Humans Archives of General Psychiatry February 1, 1994
- Monoamine oxidase inhibitors in South American hallucinogenic plants: Tryptamine and β-carboline constituents of Ayahuasca Journal of Ethnopharmacology April 1, 1984
- Human Pharmacology of Ayahuasca: Subjective and Cardiovascular Effects, Monoamine Metabolite Excretion, and Pharmacokinetics Journal of Pharmacology and Experimental Therapeutics June 18, 2003
- Subjective effects and tolerability of the South American psychoactive beverage Ayahuasca in healthy volunteers Psychopharmacology February 22, 2001
- Neurometabolic Effects of Psilocybin, 3,4-Methylenedioxyethylamphetamine (MDE) and d-Methamphetamine in Healthy Volunteers A Double-Blind, Placebo-Controlled PET Study with [18F]FDG Neuropsychopharmacology June 1, 1999
and 9 more in the library