The Effects of Psilocybin and MDMA on Resting State Hippocampal Functional Connectivity

Luke Williams

Abstract: The effects of psilocybin and MDMA on resting state hippocampal functional connectivity were analyzed in two separate studies. In the psilocybin study, 15 healthy volunteers were scanned on two separate occasions, once while receiving intravenous (IV) saline (placebo) and once while receiving 2mg of psilocybin IV. In the MDMA study, 25 healthy volunteers were scanned on two separate occasions, once after receiving a placebo pill (vitamin C), and once after receiving 100mg of MDMA HCl per Os. Hippocampal functional connectivity analyses for the MDMA study are currently underway. In addition to helping broaden our understanding of the mechanism of psychedelic drugs, the results may help inform our understanding of the DMN and its functional relationship with the hippocampus, and to explain how MDMA differs from psilocybin in its effects on hippocampal functional connectivity.

Luke Williams has a long-standing interest in psychedelic science. He originally studied philosophy and history of science, then completing Master’s degrees in history and philosophy of science from Cambridge University and philosophy from Sussex University, with a focus on enactive/phenomenological approaches to cognitive science. After a period outside academia, Luke is currently completing an MSc in cognitive neuroscience at Birkbeck, University of London, with his research project based at Imperial College’s neuropsychopharmacology unit, supervised by Robin Carhart-Harris, involving the study of functional connectivity in humans under psilocybin and MDMA.

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