Overview
- Researchers from UCSF and Imperial College reported Tuesday in Nature Communications that a first 25 mg psilocybin session in 28 healthy, psychedelic‑naive adults produced measurable brain changes and self‑reported benefits lasting up to a month.
- EEG showed higher “entropy” — more varied neural activity — within an hour of dosing, and larger spikes in this signal tracked with greater psychological insight reported the next day.
- Participants who gained more insight tended to report better well‑being and improved cognitive flexibility a month later, with roughly 70% saying their well‑being had increased at two and four weeks.
- Diffusion MRI one month after dosing found reduced water movement in tracts linking the prefrontal cortex to deeper brain regions, a pattern consistent with denser pathways but with uncertain biological meaning.
- The study used a 1 mg low‑dose control before the high dose and followed volunteers for only one month, and both authors and outside experts called the findings preliminary as U.S. policy changes and FDA fast‑track actions speed larger clinical trials.