Effects of Psilocybin and MDMA on Resting State Hippocampal Functional Connectivity - Luke Williams

Psilocybin and MDMA have distinct impacts on resting state functional connectivity in the hippocampus, a brain region central to memory and navigation. Neuroimaging studies indicate that psilocybin primarily disrupts the default mode network, manifesting as reduced hippocampal connectivity. This effect likely alters perception and self-referential processes, as the default mode network functions as a top-down regulator of cognitive states. MDMA presents a different pattern of neurological influence, with broader shifts across limb and frontal areas, rather than the more localized effects observed with psilocybin. These findings reflect their differing pharmacological mechanisms, where psilocybin acts as a 5-HT2A agonist, while MDMA functions primarily as a serotonin releaser, leading to significantly different impacts on the brain's internal signaling networks.