An investigation of acute Physiological and Psychological Moderators of Psychedelic-induced Personality Change among Healthy Volunteers

This re-analysis of a single-blind, fixed-order trial (n=28) investigates the effects of a single high-dose psilocybin (25 mg) on personality traits in psychedelic-naïve healthy volunteers. It finds significant reductions in neuroticism one month post-administration, moderated by subjective experience meaningfulness and ego dissolution, suggesting psilocybin catalyses lasting personality changes with therapeutic potential.

Abstract of An investigation of acute Physiological and Psychological Moderators of Psychedelic-induced Personality Change among Healthy Volunteers

“This study investigated the effects of a single high-dose of psilocybin on personality traits in psychedelic-naïve healthy volunteers. These data originate from a larger within-subjects fixed-order design trial, where a single high dose of psilocybin (25 mg) was administered in a psychologically supportive setting and was compared against a (one-month) prior, 1 mg ‘placebo’ dose. Personality shifts were assessed by the Big Five Inventory and the Big Five Aspect Scale, while the Altered States of Consciousness questionnaire (5D-ASC) and the Psychological Insight Scale gauged the acute psychological effects of the substance. Electroencephalography provided neurophysiological insights, specifically examining alpha power and Lempel-Ziv complexity (LZc). Results indicated significant reductions in neuroticism one month after 25 mg psilocybin administration, a finding consistent with prior studies. Reductions in neuroticism were moderated by the subjective meaningfulness of the psychedelic experience, as well as by the dread of ego dissolution subscale of the 5D-ASC, suggesting a relationship between acute drug effects and enduring personality alterations. Thus, this study substantiates the role of acute psychedelic states in catalysing lasting personality transformations in a generally beneficial direction, with broader implications for therapeutic applications and understanding of personality dynamics.”

Authors: Kate Godfrey, Brandon Weiss, Xinhu Zhang, Meg J. Spriggs, Joseph M. Peill, Taylor Lyons, Robin L. Carhart-Harris & David Erritzoe

Summary of An investigation of acute Physiological and Psychological Moderators of Psychedelic-induced Personality Change among Healthy Volunteers

This study investigates the effects of a single high-dose (25 mg) of psilocybin on personality traits in healthy, psychedelic-naïve volunteers. It aims to determine whether acute psychological and neurophysiological responses during the psychedelic experience can predict long-term personality changes. Classical psychedelics, such as psilocybin and LSD, are known to induce profound alterations in consciousness, including emotional breakthroughs, sensory distortions, and feelings of connectedness. These experiences are thought to catalyse lasting psychological transformations, particularly in traits associated with emotional regulation and openness.

Prior research has highlighted the potential of psychedelics to influence personality traits, with studies often reporting increases in openness and reductions in neuroticism. However, variability in findings suggests that individual differences in subjective and neurobiological responses may moderate these outcomes. The present study builds on this foundation by exploring both psychological experiences and neurophysiological markers, such as brain activity complexity, to identify predictors of enduring personality changes.

The authors hypothesised that neuroticism would decrease and openness would increase following the 25 mg dose but not after the 1 mg placebo dose. They also examined whether acute psychological effects, including mystical and challenging experiences, and neurophysiological markers like brain complexity, would predict the magnitude of personality changes.

Methods

Study Design

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Find this paper

An investigation of acute Physiological and Psychological Moderators of Psychedelic-induced Personality Change among Healthy Volunteers

https://doi.org/10.1016/j.nsa.2024.104092

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Cite this paper (APA)

Godfrey, K., Weiss, B., Zhang, X., Spriggs, M., Peill, J., Lyons, T., ... & Erritzoe, D. (2024). An investigation of acute Physiological and Psychological Moderators of Psychedelic-induced Personality Change among Healthy Volunteers. Neuroscience Applied, 104092.

Study details

Compounds studied
Psilocybin

Topics studied
Healthy Subjects Personality

Study characteristics
Original Re-analysis Single-Blind Within-Subject

Participants
28 Humans

Institutes

Institutes associated with this publication

Imperial College London
The Centre for Psychedelic Research studies the action (in the brain) and clinical use of psychedelics, with a focus on depression.

Compound Details

The psychedelics given at which dose and how many times

Psilocybin 1 - 25
mg | 2x

Linked Research Papers

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