Key finding — The intensity of the subjective psychedelic experience tracked directly with 5-HT2A receptor occupancy and blood psilocin levels, confirming the receptor mechanism in living humans.
Study at a glance
| Field | Detail |
|---|---|
| Institution | University of Copenhagen |
| Design | Within-subject pharmacology and PET study |
| Sample size | 8 participants |
| Intervention | Oral psilocybin with PET imaging and plasma sampling |
| Year | 2019 |
| Condition | Healthy volunteers (pharmacology) |
| Journal | Neuropsychopharmacology |
| Evidence | established |
Limitations
Very small sample; PET occupancy modeling involves assumptions, and healthy volunteers may differ from clinical populations.
Editorial note
A mechanistic study that directly linked the felt intensity of a psilocybin experience to receptor occupancy and drug levels in the body — closing part of the gap between molecule and experience.
Summary written by MMI Editorial for clarity. Always consult the primary source for full methodology and results. The confidence rating reflects our assessment of evidence strength.