Effects of Ayahuasca on the human EEG
Neville S. Arachchige Don, Bruce E. Mcdonough, Gabriel Acácio de Moura, Charles R. Warren, K. Kawanishi, Hisako Tomita, Yoshihisa Tachibana, M. Böhlke, N.r. Farnsworth
Phytomedicine April 1, 1998 DOI: 10.1016/s0944-7113(98)80003-2 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 11 |
| Population | Members of the Santo Daime Doctrine, a Brazilian shamanistic religion |
| Intervention | Ayahuasca |
| Dose | 75 ml |
| Topics | Ayahuasca LSD |
| Keywords | Harmaline Harmine Electroencephalography Hallucinogen Scalp Ingestion Audiology Pharmacology Anesthesia |
| Citations | 33 |
| Key findings | Ingestion of ayahuasca increased 36-44 Hz EEG power from posterior scalp regions, consistent with intensified visual imagery. |
Abstract
EEG data were recorded under field conditions from 11 members of the Santo Daime Doctrine, a Brazilian shamanistic religion, before and after ingesting the psychoactive alkaloid preparation, ayahuasca, or daime, as they term it. Post-ingestion, we observed increases in power in the 36-44 Hz frequency band ("40 Hz") from the left occipital-temporal-parietal scalp electrodes in the eyes-closed condition, which extended to most of the posterior scalp in the eyes-open condition. The results are consistent with many reports that ayahuasca intensifies visual imagery. These results are discussed in terms of a thalamocortical model of the role of 40 Hz activity in brain function and conscious experience. We also noted tendencies toward decreases in the power of slow (theta and alpha) brain rhythms, and increases in the 14-30 Hz beta band, in accord with studies reported 30 years ago with other consciousness-altering compounds. Analysis of four ayahuasca samples yielded an average composition per ingested dose (75 ml) of 55.6 mg harmine, 43.9 mg tetrahydroharmine, 41.3 mg N,N-dimethyltryptamine (DMT), 4.6 mg harmaline, and 3.1 mg harmol. The DMT appeared to be of sufficient concentration to promote psychoactive effects, while the β-carbolines functioned to supply MAO inhibitors necessary to prevent degradation of DMT and to maintain its oral activity.
Comparable studies
Other observational and cohort studies on ayahuasca, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Antidepressant effects of a single dose of ayahuasca in patients with recurrent depression: a preliminary report Patients with a depressive disorder | 2015 | Observational study | |
| The Psychedelic State Induced by Ayahuasca Modulates the Activity and Connectivity of the Default Mode Network Experienced subjects | 2015 | Observational cohort | n = 10 |
| Human Psychopharmacology of Hoasca, A Plant Hallucinogen Used in Ritual Context in Brazil Long-term members of a syncretic church that uses hoasca as a psychoactive sacrament... | 1996 | Observational cohort with matched controls | n = 30 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Personality, Psychopathology, Life Attitudes and Neuropsychological Performance among Ritual Users of Ayahuasca: A Longitudinal Study Regular ayahuasca users and active controls in non-ayahuasca religions | 2012 | Observational cohort | n = 242 |
Citations in the library
Cited by 25
- The Therapeutic Potentials of Ayahuasca: Possible Effects against Various Diseases of Civilization. Frontiers in Pharmacology March 2, 2016
- Models of psychedelic drug action: modulation of cortical-subcortical circuits Brain October 22, 2021
- Ayahuasca: Psychological and Physiologic Effects, Pharmacology and Potential Uses in Addiction and Mental Illness Current Neuropharmacology March 2, 2018
- Topographic pharmaco‐EEG mapping of the effects of the South American psychoactive beverage ayahuasca in healthy volunteers British Journal of Clinical Pharmacology June 1, 2002
- Acute Biphasic Effects of Ayahuasca PLoS One September 30, 2015
and 20 more in the library
Cites 5
- Dose-Response Study of N,N-Dimethyltryptamine in Humans Archives of General Psychiatry February 1, 1994
- Human Psychopharmacology of Hoasca, A Plant Hallucinogen Used in Ritual Context in Brazil The Journal of Nervous and Mental Disease February 1, 1996
- Platelet serotonin uptake sites increased in drinkers ofayahuasca Psychopharmacology November 1, 1994
- A Pharmacologic Analysis of the Functions of the Spontaneous Electrical Activity of the Cerebral Cortex The Journal of Nervous and Mental Disease September 1, 1954
- Ritual and medicinal plants of the Ese'ejas of the Amazonian rainforest (Madre de Dios, Perú). Journal of Ethnopharmacology May 1, 1996