Clarifying and measuring the characteristics of experiences that involve a loss of self or a dissolution of its boundaries.

Mystical experience, non-dual awareness, selflessness, self-transcendent experience, and ego-dissolution have become increasingly prominent constructs in meditation and psychedelic research. However, these constructs and their measures tend to be highly overlapping, imprecise, and poorly integrated with similar pathological experiences. The present study seeks to clarify the common factors involved in the characteristics of these experiences using precise distinctions across an array of experience contexts (including meditation, psychedelics, and psychopathology). Participants (N = 386) completed an online survey about an experience that involved either a dissolution of self-boundaries or a loss of selfhood. Confirmatory factor analyses resulted in 16 experience characteristics, including multiple types of changes in sense of self, co-occurring phenomenology, and cognitive and affective responses. Qualitative thematic analysis provided rich descriptions of experience characteristics. Taken together, results lead to a more specific measurement model and descriptive account of experiences involving a loss of self or self-boundary.