Psilocybin desynchronizes brain networks
OpenAlex – August 24, 2023
Source: OpenAlex
Summary
Psilocybin, a potent hallucinogen and alkaloid, acutely generated over 3-fold greater brain network changes than methylphenidate in healthy adults (17 MRI visits each). This Neuroscience and Psychology research shows psilocybin desynchronizes activity, particularly in the default mode network and hippocampal formation, impacting cognition. Relevant to Psychedelics and Drug Studies, its neurotransmitter receptor influence on behavior reduced hippocampus-cortex connectivity for weeks. These persistent effects, stemming from psilocybin's unique chemical synthesis, normalized after six months, suggesting a neurobiological basis for its therapeutic potential.
Abstract
1 Summary The relationship between the acute effects of psychedelics and their persisting neurobiological and psychological effects is poorly understood. Here, we tracked brain changes with longitudinal precision functional mapping in healthy adults before, during, and for up to 3 weeks after oral psilocybin and methylphenidate (17 MRI visits per participant) and again 6+ months later. Psilocybin disrupted connectivity across cortical networks and subcortical structures, producing more than 3-fold greater acute changes in functional networks than methylphenidate. These changes were driven by desynchronization of brain activity across spatial scales (area, network, whole brain). Psilocybin-driven desynchronization was observed across association cortex but strongest in the default mode network (DMN), which is connected to the anterior hippocampus and thought to create our sense of self. Performing a perceptual task reduced psilocybin-induced network changes, suggesting a neurobiological basis for grounding , connecting with physical reality during psychedelic therapy. The acute brain effects of psilocybin are consistent with distortions of space-time and the self. Psilocybin induced persistent decrease in functional connectivity between the anterior hippocampus and cortex (and DMN in particular), lasting for weeks but normalizing after 6 months. Persistent suppression of hippocampal-DMN connectivity represents a candidate neuroanatomical and mechanistic correlate for psilocybin’s pro-plasticity and anti-depressant effects.