Depressive DisordersNeuroimaging & Brain MeasuresPersonality & Trait FactorsAyahuasca

Modulatory effects of ayahuasca on personality structure in a traditional framework

This mixed-design study (n=48) finds significant increases in agreeableness and reductions in neuroticism post-ayahuasca administration (n=24), sustained at 6-month follow-up, with trait level increases in openness also observed at follow-up. The study also reports an association between greater perceived mystical experience and increased reductions in neuroticism.

Authors

  • Netzband, N.
  • Ruffell, S.
  • Linton, &. S.

Published

Psychopharmacology
individual Study

Abstract

Ayahuasca is a psychoactive plant brew containing dimethyltryptamine (DMT) and monoamine oxidase inhibitors (MAOIs). It originates from the Amazon basin, where it is used primarily for ceremonial purposes. Ayahuasca tourists are now entering certain communities seeking alternative physical or psychological healing, as well as spiritual growth.

Rationale

Recent evidence has shown that the similar acting psychedelic compound, psilocybin, facilitated long-term increases in trait openness following a single administration.

Objectives

This paper assesses the impact of ayahuasca on personality in a traditional framework catering for ayahuasca tourists.

Method

Within a mixed design, we examined the effect of ayahuasca on participants’ personality (measured by the NEO Personality Inventory 3 questionnaire) across time (pre- to post-ayahuasca administration, and 6-month follow-up), relative to a comparison group (who did not ingest ayahuasca).

Results

The results demonstrated significant increases in agreeableness pre- and post-ayahuasca administration and significant reductions in neuroticism in 24 participants, relative to the comparison group. Both of these changes were sustained at 6-month follow-up, and trait level increases were also observed in openness at this stage. Additionally, greater perceived mystical experience (measured using the Mystical Experience Questionnaire 30) was associated with increased reductions in neuroticism.

Conclusions

These findings, which indicate a positive mediating effect of ayahuasca on personality, support the growing literature suggesting potential therapeutic avenues for serotonergic psychedelics.

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Research Summary of 'Modulatory effects of ayahuasca on personality structure in a traditional framework'

Introduction

Netzband and colleagues frame ayahuasca as an Amazonian plant brew containing DMT plus MAO inhibitors, used traditionally in ceremonial contexts and increasingly by international ‘ayahuasca tourists’. The introduction notes mechanistic links between serotonergic 5-HT2A receptor agonism and alterations in brain networks such as the default mode network, and it summarises prior human and animal evidence that single or occasional administrations of serotonergic psychedelics (including psilocybin and ayahuasca) can produce rapid antidepressant effects and longer-term changes in mood, cognition and some personality domains. Building on earlier studies that reported increases in openness and other trait-level changes after psychedelics, the study aimed to evaluate whether participation in a 12-day, Shipibo-style ayahuasca retreat adapted for tourists would modulate personality structure. The investigators set out to measure short-term (post-retreat) and six-month follow-up changes in Big Five personality domains (using the NEO-PI3), and to test whether the intensity of perceived mystical experience (MEQ30) related to any personality changes. The setting was an indigenous Shipibo community–based retreat in the Peruvian Amazon that caters to international participants.

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Study Details

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