Biological psychiatry
February 1, 2023
Devon Stoliker, Leonardo Novelli, Franz X Vollenweider et al.
49 citations
Under the peak effect of LSD, the inhibitory influence from the salience network to the default mode network becomes excitatory, and inhibition from the default mode network to the dorsal attention network weakens. These changes in effective connectivity between resting-state networks may reduce their normal anticorrelation, offering a neural mechanism for ego dissolution—the blurring of the boundary between self and world. The findings suggest that alterations in the sense of self across different conscious states depend on the organized balance of effective connectivity among these networks.
Biological Psychiatry
January 5, 2024
Devon Stoliker, Leonardo Novelli, Adeel Razi et al.
42 citations
Temporary reduction in amygdala signaling is linked to changes in how brain networks connect at rest. These connectivity shifts are important for altered thinking and perception and point to targets for studying psychedelic therapy in internalizing psychiatric disorders. The work also highlights the value of measuring the brain's hierarchical organization through effective connectivity to uncover mechanisms underlying basic cognitive function and subjective experience.
Molecular psychiatry
April 1, 2025
Devon Stoliker, Katrin H Preller, Leonardo Novelli et al.
19 citations
Psilocybin, the active compound in magic mushrooms, alters visual perception by changing how brain regions communicate. Under psilocybin, early visual areas and higher visual-association regions showed increased self-inhibition, reducing sensitivity to incoming neural signals. At the same time, top-down feedback from visual-association areas to earlier visual regions was enhanced. This shift in balance—less bottom-up sensitivity and stronger top-down influence—may explain the vivid eyes-closed imagery characteristic of psychedelic experiences. The findings come from a double-blind, placebo-controlled study of 24 healthy adults using functional MRI and dynamic causal modeling, and they advance understanding of both basic visual perception and potential clinical applications.
bioRxiv (Cold Spring Harbor Laboratory)
March 11, 2025
Devon Stoliker, Leonardo Novelli, Moein Khajehnejad et al.
8 citations
preprint
Psychedelics like psilocybin alter consciousness by reorganizing brain connectivity in a context-sensitive way. In the largest psychedelic neuroimaging dataset to date, 62 adults underwent functional MRI and EEG before and after ingesting 19 mg of psilocybin, during rest and naturalistic stimuli. Under psilocybin, brain signals during eyes-closed conditions became similar to those during eyes-open conditions, with increased global functional connectivity in associative regions and decreased connectivity in sensory areas. Machine learning linked subjective effects to structured neural activity patterns. Stronger self-dissolving effects were associated with more distinct neural representations and next-day mindset changes, revealing a state of 'embeddedness' where networks that usually segregate internal and external processing integrate coherently, aligning neural dynamics with context.
medRxiv
September 9, 2022
Devon Stoliker, Katrin H. Preller, Leonardo Novelli et al.
5 citations
preprint
A double-blind, placebo-controlled study of 24 healthy adults found that psilocybin, the active compound in magic mushrooms, alters visual brain connectivity in ways consistent with preclinical models. Under psilocybin, early visual and higher visual-association regions showed increased self-inhibition, while top-down feedback from association areas to earlier visual regions was enhanced. These connectivity changes were linked to decreased sensitivity to neural inputs and the perception of eyes-closed visual imagery. The findings suggest that psilocybin-induced visual imagery arises from reduced bottom-up gain and strengthened top-down influences, informing basic and clinical understanding of visual perception.
medRxiv
September 9, 2022
Devon Stoliker, Leonardo Novelli, Franz X. Vollenweider et al.
4 citations
preprint
Psilocybin reduces the brain's top-down control from resting state networks to the amygdala, which is involved in emotion appraisal and regulation. In a randomized, double-blind, placebo-controlled trial of 24 healthy adults given 0.215 mg/kg psilocybin, effective connectivity decreased from the default mode network and salience network to the amygdala, and within the DMN and SN, while connectivity within the central executive network increased. These changes were linked to altered emotion and meaning under the drug, suggesting that attenuation of the amygdala signal may serve as a biomarker for psilocybin's therapeutic effects in conditions like addiction and depression.
bioRxiv (Cold Spring Harbor Laboratory)
April 14, 2025
Leonardo Novelli, Devon Stoliker, Tamrin Barta et al.
3 citations
preprint
PsiConnect is a large-scale neuroimaging study that examined brain activity in 62 participants before and after a 19 mg dose of psilocybin using functional, structural, and diffusion-weighted MRI combined with EEG. The design included resting-state scans and three naturalistic conditions: guided meditation, music listening, and movie watching. Half of the participants completed an 8-week meditation training program, allowing exploration of interactions among meditation, psilocybin, and brain function. Multi-echo fMRI improved signal-to-noise ratio and reduced artifacts. Behavioral and self-report measures captured acute and longitudinal effects, with follow-ups extending to one year. The data is curated according to open science principles.
Scientific data
May 21, 2026
Leonardo Novelli, Devon Stoliker, Tamrin Barta et al.
PsiConnect is a large-scale neuroimaging study that investigates how psilocybin affects brain activity and subjective experience depending on context. Sixty-two participants received a 19 mg dose of psilocybin and underwent functional, structural, and diffusion-weighted MRI, as well as EEG, before and after administration. Scans included resting-state and three naturalistic conditions: guided meditation, music listening, and movie watching. Half of the participants completed an 8-week meditation training program, allowing examination of interactions between meditation, psilocybin, and brain function. Multi-echo fMRI improved signal quality. Behavioral and self-report measures captured acute and long-term effects, with follow-ups up to one year. Data is openly shared to support future research.
bioRxiv (Cold Spring Harbor Laboratory)
August 22, 2025
Matthew D. Greaves, Tamrin Barta, Leonardo Novelli et al.
preprint
Psilocybin reorganizes directed influences between brain regions while preserving the underlying structural connectivity, according to fMRI data analyzed with a dynamic causal model. Across four contexts—rest, guided meditation, music listening, and movie viewing—effects converged on outgoing influences from the left hippocampus, a hub linking memory and association systems with the default-mode network and thalamus. The left-hippocampus-to-thalamus pathway showed a sign-reversed association with mystical-experience scores: downregulation during guided meditation and upregulation during music listening. Left-hippocampal efferents predicted individual differences in mystical-experience intensity in cross-validation, and a simpler measure of hippocampal signal variability showed modest associations.