From Ego to Death: Validation of the Ego-Dissolution Scale (EDS)

Disruptions to the sense of self are dotted across cultures and times in rituals involving hallucinogens, sensory deprivation, trance possession, and meditation. Much of the research on the self or “ego” suggests that the self is a complicated, multi-faceted entity and that there are many aspects that hold together our ego. Yet, current measurements on ego-dissolution focus on a narrow definition of the self. The present study focuses on experiences of ego-dissolution occasioned by the classical psychedelics ayahuasca, DMT, LSD, and psilocybin (magic mushrooms). I compiled a thirty-four item self-report questionnaire with items from relevant factors in three pre-existing validated questionnaires: the Ego-Dissolution Inventory, Mystical Experience Questionnaire, and the Abnormal Mental States Questionnaire. The compiled scale was distributed as an online survey (n = 207) and subjected to an exploratory factor analysis. I extracted six factors related to ego-dissolution: Dissolving of Identity, Dissolving of Physical Body, Dissolving into Environment, Experiences of Eternity, Clarity about Life and Purpose, and Pleasure. The revised scale showed excellent reliability. Ayahuasca and DMT were found to have similar experiences, scoring high on the ego-dissolution factors, and LSD and psilocybin were similar with moderate scores. The two groups were significantly different from each other. Overall, all psychedelics provided new insights into one’s life, and were pleasurable. Dosage was not found to have a significant effect. The revised scale provides a nuanced approach to characterising experiences of ego-dissolution occasioned by classical psychedelics.