Simon Ruffell

Simon Ruffell

King’s College London

Modulatory Effects of Ayahuasca on Personality Structure in an Adapted Traditional Framework


Ayahuasca is a powerful psychoactive plant brew mix containing dimethyltryptamine (DMT) and monoamine oxidase inhibitors (MAOIs). Ayahuasca tourists have begun entering communities in the Amazon basin seeking alternative physical and/or psychological healing, as well as spiritual growth. Sensationalist media representations have resulted in exponential increases in tourism, highlighting the need for a thorough understanding of the brew.

This paper assesses the impact of ayahuasca on personality in a modified traditional framework adapted for ayahuasca tourists. Personality is typically deemed to be stable above the age of 30, and is measured using the five-factor model (NEO-PI3). Changes in personality are correlated with the extent of a perceived Mystical Experience (measured by MEQ30), following six ayahuasca sessions. Rationale was based on Maclean et al. (2011) who found that a similar compound, psilocybin, caused long term increases in levels of Openness on the NEO-PI after a single administration. Current study sample group (N=24) found significant increases in levels of Agreeableness from pre to post ingestion, along with significant reductions in levels of Neuroticism. Changes in both traits were sustained at the six month follow up. Trait level increases were also observed in Openness. Changes in Neuroticism were found to correlate negatively with perceived Mystical Experience.

The authors will then introduce for the first time their current research into the impact of ayahuasca on trauma-related conditions in an adapted traditional setting. This project has kindly been funded by the British Medical Research Council, comprising a sample group of 65.


Simon graduated with a degree in medicine from the University of Sheffield before specialising in psychiatry. He has an interest in transcultural psychiatry, working overseas in Northern Uganda. He has a special interest in psychedelic research, namely ayahuasca and has spent the last three years conducting research into the use of ayahuasca in an adapted traditional setting for ayahuasca tourists in the Peruvian Amazon. Simon is currently based at The Maudsley Hospital in South London, as well as working as a Senior Research Associate at King’s College London looking at the use of psilocybin in treatment resistant depression.



Learn about new events and breakthroughs in the psychedelic scientific community.