Skip to content

Acute psilocybin effects on CBF and ICA diameter

Kristian Larsen

Figshare 2026 DOI: 10.6084/m9.figshare.31064788.v1 (opens in new tab)

Study at a glance

AI-extracted from the abstract
Characteristics Observational cohort Peer reviewed
Sample size 28
Population Healthy human participants
Intervention Psilocybin
Dose 0.2–0.3 mg/kg
Topics Psilocybin
Keywords Cerebral blood flow Internal carotid artery Carotid arteries Anesthesia Cardiology Hemodynamics Cerebral circulation Cerebral perfusion pressure Middle cerebral artery Magnetic resonance imaging Cerebral blood volume Circulatory system
Key findings Psilocybin reduces whole-brain cerebral blood flow and internal carotid artery diameter in a dose-dependent manner, with higher plasma psilocin levels linked to greater reductions.

Abstract

This figure shows the acute effects of psilocybin on cerebral blood flow and internal carotid artery diameter in healthy human participants. Whole-brain cerebral blood flow was measured using pseudo-continuous arterial spin labelling MRI at baseline, during the peak and late phases following psilocybin administration (0.2–0.3 mg/kg, N = 28). Cerebral blood flow maps illustrate widespread cortical reductions at peak plasma psilocin levels. Plasma psilocin concentrations were negatively associated with both whole-brain cerebral blood flow and internal carotid artery diameter, indicating dose-dependent effects. MRI acquisition, preprocessing, and statistical modelling procedures are described in detail in Larsen et al. (Journal of Cerebral Blood Flow & Metabolism, 2025).

Explore topics