A single high dose of psilocybin (25 mg) in 28 healthy, psychedelic-naive participants produced anatomical and functional brain changes lasting from one hour to one month. At one month, participants showed increased cognitive flexibility, psychological insight, and well-being. Diffusion tensor imaging revealed decreased axial diffusivity in prefrontal-subcortical tracts, correlating with reduced brain network modularity. Decreased modularity negatively correlated with increased well-being, consistent with depression findings. Increased cortical signal entropy one to two hours after dosing predicted improved well-being at one month, mediated by next-day psychological insight. No effects occurred with a 1 mg placebo dose.
People with a lifetime eating disorder diagnosis who planned to take a psychedelic drug showed improvements in depression and psychological wellbeing two weeks afterward. Twenty-eight participants completed depression and wellbeing measures before and after a psychedelic experience; twenty-seven also reported on emotional breakthrough during the experience. Bayesian analyses indicated strong evidence for reduced depressive symptoms and increased wellbeing after the psychedelic experience, with marginal evidence linking emotional breakthrough to those improvements. The findings suggest positive psychological aftereffects relevant to eating disorder treatment and encourage further clinical trials of psychedelic-assisted therapy for eating disorders.