P. Anderer

University of Vienna

2 papers in the library · 257 citations · publishing 2002-2004

Papers

Effects of the South American Psychoactive Beverage Ayahuasca on Regional Brain Electrical Activity in Humans: A Functional Neuroimaging Study Using Low-Resolution Electromagnetic Tomography

Neuropsychobiology January 1, 2004 Jordi Riba, P. Anderer, F Jané et al. 131 citations

Ayahuasca, a South American psychotropic plant tea, combines monoamine oxidase-inhibiting β-carboline alkaloids with the psychedelic agent DMT. In a clinical study with 18 volunteers, freeze-dried ayahuasca (0.85 mg DMT/kg body weight) produced dose-dependent changes in spontaneous brain electrical activity, measured via electroencephalography and low-resolution electromagnetic tomography (LORETA). Compared to placebo, ayahuasca decreased power density in alpha-2, delta, theta, and beta-1 frequency bands 60 and 90 minutes after dosing. Power decreases in delta, alpha-2, and beta-1 bands occurred predominantly over the temporo-parieto-occipital junction, while theta power reduced in temporomedial and frontomedial regions. Subjective effects increased across all six scales of the Hallucinogen Rating Scale. The findings suggest involvement of unimodal and heteromodal association cortex and limbic structures in ayahuasca's psychological effects.

DOI: 10.1159/000077946 Ayahuasca Psychology Hallucinogen Neuroscience +4

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 Jordi Riba, P. Anderer, Adelaida Morte et al. 126 citations

Ayahuasca, a psychoactive tea from South America, produces measurable changes in brain electrical activity that parallel its subjective psychedelic and stimulant effects. In a double-blind crossover trial, 18 volunteers received low and high doses of freeze-dried ayahuasca. Electroencephalography recordings from baseline to eight hours showed dose-dependent decreases in absolute power across all frequency bands, especially theta, and decreases in relative delta and theta power with increases in beta power. Effects began within 15–30 minutes, peaked between 45 and 120 minutes, and returned to baseline by four to six hours. The pattern resembles that of other serotonergic psychedelics and supports the role of 5-HT2 and dopamine D2 receptor activation.

DOI: 10.1046/j.1365-2125.2002.01609.x Ayahuasca Hallucinogen Placebo Crossover study +6