“…These psychedelic effects of psilocybin are mediated primarily by its actions as an agonist at the serotonin 2A receptor (5‐HT 2A R) (Vollenweider, Vollenweider‐Scherpenhuyzen, Babler, Vogel, & Hell, ). The 5‐HT 2A R is an excitatory 5‐HT receptor in the human brain most highly expressed throughout the cerebral cortex (Beliveau & Ganz, ; Varnas, Halldin, & Hall, ), and dysfunction of 5‐HT 2A R is implicated in neuropsychiatric disorders including depression and schizophrenia (Albert, Benkelfat, & Descarries, ; Bhagwagar et al, ; Lin, Jiang, Kan, & Chu, ; Naughton, Mulrooney, & Leonard, ; Nikolaus, Muller, & Hautzel, ). It is therefore possible that 5‐HT 2A R‐mediated effects of psilocybin and other psychedelics contribute to enduring increases in trait Openness.…”