Psilocybin disrupts sensory and higher order cognitive processing but not pre-attentive cognitive processing—study on P300 and mismatch negativity in healthy volunteers
Psychopharmacology January 5, 2018 Anna Bravermanová, Michaela Viktorinová, Filip Tylš et al. 50 citations
Psilocybin, a psychedelic that activates 5-HT2A receptors, disrupted early perceptual and higher-order cognitive processing in healthy volunteers but left pre-attentive cognition intact. In a double-blind, placebo-controlled crossover trial, 20 participants (10 men, 10 women) received 0.26 mg/kg of psilocybin orally. The drug produced robust psychedelic effects and psychotic-like symptoms, decreased the amplitude of the P300 event-related potential (a marker of attentive processing) and the N100 (an early perceptual marker), but did not affect mismatch negativity (MMN), a measure of pre-attentive processing. The disruption of P300 correlated with the intensity of the psychedelic state, which depended on psilocin serum levels. These findings suggest that 5-HT2A receptors play a role in altered information processing in psychosis and schizophrenia, particularly at early perceptual and higher-order cognitive levels.