Effects of psilocybin on hippocampal neurogenesis and extinction of trace fear conditionning CATLOW B.J., SONG S., PAREDES D.A., KIRSTEIN C.L., SANCHEZ-RAMOS J. Experimental Brain Research, 2013, 228, 481-491. Doi : 10.1007/s00221-013-3579-0   Abstract Drugs that modulate serotonin (5-HT) synaptic concentrations impact neurogenesis and hippocampal (HPC)-dependent learning. The primary objective is to determine the extent to which psilocybin (PSOP) modulates neurogenesis and thereby affects acquisition and extinction of HPC-dependent trace fear conditioning. PSOP, the 5-HT2A agonist 25I-NBMeO and the 5-HT2A/C antagonist ketanserin were administered via an acute intraperitoneal injection to mice. Trace fear conditioning was measured as the amount of time spent immobile in the presence of the conditioned [...]