Trial PaperPTSDAnxiety DisordersPersonality & Trait FactorsInterpersonal Functioning & Social ConnectednessMDMA

Therapeutic effect of increased openness: investigating mechanism of action in MDMA-assisted psychotherapy

In a randomised trial of MDMA-assisted psychotherapy for chronic, treatment-resistant PTSD, participants showed long-term increases in Openness and decreases in Neuroticism, and increased Openness (but not reduced Neuroticism) moderated the relationship between MDMA treatment and reductions in PTSD symptoms. These findings suggest MDMA-assisted psychotherapy can produce enduring personality change—particularly heightened Openness—that may act as a mechanism for therapeutic improvement.

Authors

  • Rick Doblin
  • Berra Yazar-Klosinski
  • Michael Mithoefer

Published

Journal of Psychopharmacology
individual Study

Abstract

A growing body of research suggests that traumatic events lead to persisting personality change characterized by increased neuroticism. Relevantly, enduring improvements in Post-Traumatic Stress Disorder (PTSD) symptoms have been found in response to 3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy. There is evidence that lasting changes in the personality feature of “openness” occur in response to hallucinogens, and that this may potentially act as a therapeutic mechanism of change. The present study investigated whether heightened Openness and decreased Neuroticism served as a mechanism of change within a randomized trial of MDMA-assisted psychotherapy for chronic, treatment-resistant PTSD. The Clinician-Administered PTSD Scale (CAPS) Global Scores and NEO PI-R Personality Inventory (NEO) Openness and Neuroticism Scales served as outcome measures. Results indicated that changes in Openness but not Neuroticism played a moderating role in the relationship between reduced PTSD symptoms and MDMA treatment. Following MDMA-assisted psychotherapy, increased Openness and decreased Neuroticism when comparing baseline personality traits with long-term follow-up traits also were found. These preliminary findings suggest that the effect of MDMA-assisted psychotherapy extends beyond specific PTSD symptomatology and fundamentally alters personality structure, resulting in long-term persisting personality change. Results are discussed in terms of possible mechanisms of psychotherapeutic change.

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Research Summary of 'Therapeutic effect of increased openness: investigating mechanism of action in MDMA-assisted psychotherapy'

Introduction

The paper frames PTSD not only as a cluster of re-experiencing, avoidance, and hyperarousal symptoms but also as a condition that, for some individuals, produces enduring shifts in personality—phenomena sometimes described as "complex PTSD" or, in ICD terminology, "enduring personality change following a catastrophic experience." Earlier research links PTSD and trauma exposure with elevated Neuroticism on the NEO PI(-R), and separate lines of inquiry have shown that classic psychedelics (notably psilocybin) can produce lasting increases in the personality domain of Openness, particularly following profound or mystical-type experiences. MDMA, which has prosocial and anxiolytic pharmacological effects, has been used as an adjunct to psychotherapy for PTSD and has shown sustained reductions in PTSD symptom severity in prior work by the same group. Wagner and colleagues set out to test whether changes in two NEO PI-R personality dimensions—Openness and Neuroticism—might operate as mechanisms linking MDMA-assisted psychotherapy to reductions in PTSD symptoms. Specifically, the study reanalysed data from a randomised, placebo-controlled trial to examine whether increases in Openness and decreases in Neuroticism were associated with CAPS (Clinician-Administered PTSD Scale) score reductions at 2-month follow-up, whether MDMA produced greater personality change than therapy with placebo, and whether any personality changes persisted at long-term follow-up (LTFU) after an open-label crossover for the original placebo group.

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Study Details

References (12)

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