Multidimensional Ego-Dissolution Assessment (MEDA): Scale Development and Substance-Specific Comparisons
Rebekah Senānāyaka
March 2, 2026 preprint DOI: 10.31234/osf.io/9c6xg_v1 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Cross-sectional survey with exploratory factor analysis |
|---|---|
| Sample size | 207 |
| Population | Adults reporting profound experiences with ayahuasca, DMT, LSD, or psilocybin |
| Topics | Ayahuasca Psilocybin Ego dissolution |
| Keywords | Pleasure Clarity Exploratory factor analysis Scale ratio Cluster analysis Identity music |
| Key findings | Ayahuasca and DMT produced significantly higher dissolution scores than LSD and psilocybin across four of six ego-dissolution factors, while all substances yielded equivalent high scores on insight and pleasure dimensions. |
Abstract
Rationale: Ego-dissolution represents a key therapeutic mechanism in psychedelic-assisted therapy, yet current measurement approaches may inadequately capture its multidimensional nature.Objective: To develop and validate the Multidimensional Ego-Dissolution Assessment (MEDA) and examine substance-specific patterns across classical psychedelics.Methods: Items from three validated scales (Ego-Dissolution Inventory, Mystical Experience Questionnaire, 5D-Altered States of Consciousness) were compiled into a 34-item measure. Exploratory factor analysis was conducted on responses from 207 participants reporting profound experiences with ayahuasca (n=51), DMT (n=28), LSD (n=52), or psilocybin (n=76).Results: Factor analysis revealed a robust 6-factor structure: Dissolving of Identity (α=.94), Experiences of Eternity (α=.89), Dissolving of Physical Body (α=.80), Dissolving into Environment (α=.85), Clarity about Life and Purpose (α=.78), and Pleasure (α=.78). Two distinct substance clusters emerged: ayahuasca/DMT produced significantly higher dissolution scores than LSD/psilocybin across four factors, while all substances showed equivalent high scores on insight and pleasure dimensions. Dosage showed no significant effects.Conclusion: The MEDA provides preliminary evidence for multidimensional ego-dissolution assessment. Substance-specific clustering patterns might inform therapeutic selection, while universal insight and pleasure effects suggest core psychedelic benefits achievable across substances.
In the evidence
This study is part of the evidence base for a synthesis in the library. Here is how each one recorded it.
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A six-factor ego-dissolution structure emerged, with ayahuasca and DMT producing higher dissolution scores than LSD and psilocybin on four factors while all substances scored equivalently high on insight and pleasure; dosage showed no significant effects.
Synthesized
Comparable studies
Other cross-sectional and survey studies on ego dissolution, most cited first.