I found little consensus on terminology among the researchers I interviewed, but when I unpack their metaphors and vocabularies—whether spiritual, humanistic, psychoanalytic, or neurological—it is finally the loss of ego or self (what Jung called “psychic death”) they’re suggesting is the key psychological driver of the experience. It is this that gives us the mystical experience, the death rehearsal process, the overview effect, the notion of a mental reboot, the making of new meanings, and the experience of awe.