Explore / Peer-reviewed article
Peer-reviewed articleOpen access

Human brain changes after first psilocybin use.

Lyons T, Spriggs M, Kerkelä L, Rosas FEiD, Roseman LiD, Mediano PAMiD, Timmermann CiD, Oestreich L, Pagni BAiD, Zeifman RJ, Hampshire A, Trender WiD, Douglass HMiD, Girn MiD, Godfrey K, Kettner H, Sharif FiD, Espasiano L, Gazzaley AiD, Wall MBiD, Erritzoe DiD, Nutt DJiD, Carhart-Harris RLiD

Nature communicationsMay 5, 2026License: open accessUnited Kingdom, Australia, United States, Canada19 citationsDOI: 10.1038/s41467-026-71962-3

Abstract

Psychedelics have robust effects on acute brain function and long-term behavior but whether they also cause enduring functional and anatomical brain changes is largely unknown. In an exploratory, placebo-controlled, within-subjects, electroencephalography (EEG), and magnetic resonance imaging (MRI) study in 28 healthy, entirely psychedelic-naive participants, anatomical and functional brain changes are detected from one-hour to one-month after a single high-dose (25 mg) of psilocybin. Increases in cognitive flexibility, psychological insight, and well-being are seen at one-month. Diffusion tensor imaging (DTI) done before and one-month after 25 mg psilocybin reveals decreased axial diffusivity bilaterally in prefrontal-subcortical tracts that correlate with decreases in brain network modularity (fMRI) over the same month. Enduring functional brain changes are largely absent, but network modularity change (numerical decrease) negatively correlates with well-being change (significant increase), in line with previous findings in depression. Increased cortical signal entropy (EEG) at 1- and 2-hours post-dosing predicts improved psychological well-being at one-month. Next-day psychological insight mediates the entropy to well-being relationship. All effects are exclusive to 25 mg psilocybin; no effects occur with a 1 mg psilocybin placebo.

Topics & conditions

Detected automatically by Psychedelic Commons from the title and abstract, not labels from the source. They may be incomplete.

PsilocybinDepression

Psychedelic Commons aggregates metadata from open sources and links back to the original. Rights remain with the authors and publishers. Something wrong with this record? Report a problem.