Where the term comes from

Older writing on psychedelics calls the state ego loss or ego death; researchers mostly say ego dissolution, a term found in psychiatric work on LSD from the 1960s. In 2016 a research team published the Ego-Dissolution Inventory, an eight-item questionnaire. Across 1,828 drug experiences reported by 691 people, scores rose with dose for psychedelics but not for cocaine or alcohol, and they moved closely with a felt unity with one’s surroundings.

What the research shows

In one of the first brain-imaging studies of the state, 15 healthy volunteers received psilocybin by infusion. Stronger ego dissolution went with weaker communication between the medial temporal lobe and higher cortical regions and with a looser salience network. Its first author, Alexander Lebedev, is now a psychiatrist on our team. In a small open-label trial of 20 people with treatment-resistant depression, a strong sense of boundlessness during the session combined with little dread of losing the self explained about half of the variation in improvement five weeks later.

How it differs from related states

Ego dissolution overlaps with a mystical-type experience but is narrower: it concerns the sense of self, not sacredness or joy. Whether it is welcomed or feared is thought to depend on the person’s mindset and setting. Disturbances of the self are also considered a core feature of psychosis, one reason screening matters before any session. And a temporary loss of self is not the same as becoming less self-centered: a review of psychedelic and meditation research warns against treating the first as evidence of the second.

Related terms

Mystical-Type Experience: the broader state of unity, sacredness and timelessness.

Challenging Psychedelic Experience: when losing the sense of self turns frightening.

Set and Setting: why the same state can feel freeing or frightening.