Effects of ayahuasca on personality: results of two randomized, placebo-controlled trials in healthy volunteers
Authors:
Juliana Mendes Rocha, Giordano Novak Rossi, Flávia L. Osório, José Carlos Bouso Saiz, Gabriela de Oliveira Silveira, Mauricio Yonamine, Eduardo José Crevelin, Maria Eugênia Queiroz, Jaime E. Cecílio Hallak, and Rafael Guimarães dos Santos.
Journal:
Frontiers in Psychiatry
Year:
2021
About the study
This article presents data from two randomized, double-blind, placebo-controlled clinical trials that evaluated the effects of ayahuasca on personality traits in healthy volunteers. Considering the evidence of associated changes in personality in other classic hallucinogens, and the antidepressive and anxiolytic effects of ayahuasca, the hypothesis was that ayahuasca would produce increases in Openness and Conscientiousness scores and decreases in Neuroticism scores.
The first study was conducted from November 2017 to May 2019 in order to assess the effects of ayahuasca on emotion face recognition, as well as subjective effects, safety, and personality measures. The second study was conducted from September 2018 to March 2020, evaluating the effects of ayahuasca on emotion face recognition and empathy, as well as subjective effects, safety, and personality measures.
Compared to baseline, the association of placebo and ayahuasca in the second study increased Openness scores 21 days after drug intake, replicating previous findings with LSD and psilocybin. These changes could have a greater importance in clinical samples, such as patients with depression and anxiety.
Abstract
Rationale: Previous studies with the serotonergic hallucinogens LSD and psilocybin showed that these drugs induced changes in personality traits, such as increases in Openness. However, results are inconsistent, and the effects of ayahuasca on personality were never investigated in a controlled trial.
Objectives: To assess the effects of ayahuasca on personality in two randomized, placebo-controlled trials in healthy volunteers.
Methods: Data from two parallel-group, randomized, placebo-controlled trials in healthy volunteers were included. In the first trial, 15 volunteers ingested ayahuasca or placebo, while in the second trial 15 volunteers received placebo+ayahuasca or cannabidiol (CBD)+ayahuasca. Personality was assessed with the NEO-Five Factor Inventory (NEO-FFI) at baseline and 21 days post-treatment.
Results: There were significant differences between groups in baseline Openness scores, but not on day 21. A significant increase in Openness scores was observed in the placebo + ayahuasca group in study 2. No other within-group differences were observed for any other domain.
Conclusions: Ayahuasca produced inconsistent effects on personality since it induced significant increase in Openness 21 days post-drug intake only in one of the trials. The absence of significant differences in the other ayahuasca groups could be due to small sample sizes and baseline differences among groups. The effects of ayahuasca and other serotonergic hallucinogens on personality should be further investigated in clinical samples.
Photo by Matúš Kovačovský on Unsplash.
Categories:
Studies & papers
, Ayahuasca
Tags:
hallucinogens
, personality
, ayahuasca
, scientific research
, study
, DMT
, psychedelics