In a single‑blind cross‑over study of 28 healthy volunteers, acute psilocybin — but not the 5‑HT2A antagonist ketanserin — produced significant global and regional reductions in cerebral blood flow that correlated with plasma psilocin and subjective drug intensity (approximately 11.6% at peak). Psilocybin also caused a 10.5% constriction of the internal carotid artery, providing the first in vivo human evidence of asymmetric 5‑HT2A receptor modulation of cerebral haemodynamics.
- Published
- Journal
- Journal of Cerebral Blood Flow and Metabolism
- Authors
- Armand, S., Fisher, P. M., Johansen, A., Knudsen, G. M., Larsen, K., Lindberg, U., Madsen, M. K., McCulloch, D. E-W., Ozenne, B., Stenbæk, D. S.