Neurometabolic Effects of Psilocybin, 3,4-Methylenedioxyethylamphetamine (MDE) and d-Methamphetamine in Healthy Volunteers A Double-Blind, Placebo-Controlled PET Study with [18F]FDG
Neuropsychopharmacology June 1, 1999 E Gouzoulis-Mayfrank 224 citations
Psilocybin (0.2 mg/kg) increased glucose metabolism in right frontotemporal cortical regions, especially the anterior cingulate, and decreased metabolism in the thalamus. Both MDE (2 mg/kg) and methamphetamine (0.2-0.4 mg/kg) caused cortical hypometabolism and cerebellar hypermetabolism. Cognitive activation-related increases in left frontocortical regions were attenuated under all three substances, but less so under MDE. The psilocybin results align with studies of acute schizophrenia showing frontal overactivity at rest but diminished capacity to activate prefrontal regions during cognitive tasks. The MDE findings support the idea that entactogens form a distinct psychoactive class intermediate between stimulants and hallucinogens.