This pre-print follow-up fMRI analysis of an RCT of healthy subjects (n=24) finds that psilocybin (15mg/70kg) led to a pattern of decreased top-down effectivity between the default mode network (DMN), salience network (SN), and central executive network (CEN) to the amygdala.
“Classic psychedelics alter sense of self and patterns of self-related thought. These changes are hypothesised to underlie their therapeutic efficacy across internalising pathologies such as addiction, anxiety, and depression. Using resting-state functional MRI images from a randomised, double blinded, placebo-controlled clinical trial of 24 healthy adults under 0.215mg/kg psilocybin, we investigated the effective connectivity changes between the amygdala and the default mode network (DMN), salience network (SN) and central executive network (CEN). This connectivity underpins the appraisal and regulation of emotion and is associated with clinical symptomatology. We observed a general pattern of decreased top-down effective connectivity from the resting state networks of interest to the amygdala and directed connectivity changes associated with altered emotion and meaning under psilocybin. Our findings identify cognitive-emotional connectivity associated with the subjective effects of psilocybin and the attenuation of the amygdala as a potential biomarker of psilocybin’s therapeutic efficacy.”
Authors: Devon Stoliker, Leonardo Novelli, Franz X. Vollenweider, Gary Egan, Katrin H. Preller & Adeel Razi
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Effective connectivity of emotion and cognition under psilocybin
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Placebo-Controlled Double-Blind Randomized Follow-up Bio/Neuro
Authors associated with this publication with profiles on BlossomFranz Vollenweider
Franz X. Vollenweider is one of the pioneering psychedelics researchers, currently at the University of Zurich. He is also the director of the Heffter (sponsored) Research Center Zürich for Consciousness Studies (HRC-ZH).
Katrin Preller is one of the upcoming researchers, currently at the University of Zurich and Yale University, and is focused on the neurobiology and pharmacology of psychedelics.
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