Neuropharmacology
February 1, 2023
Marco Aqil, Leor Roseman
59 citations
Psychedelics are experiencing a resurgence in scientific and clinical interest, but no universal agreement exists on the mechanisms behind their effects on subjective experience, brain dynamics, or therapeutic benefits. The effects of psychedelics on low-level sensory—particularly visual—dimensions and corresponding brain dynamics have often been dismissed as epiphenomenal byproducts. Reviewing evidence from neuroimaging, pharmacology, questionnaires, and clinical studies, the authors propose that psychedelic-induced alterations in low-level sensory dimensions are not entirely reducible to high-level alterations but co-occur in a dialogical interplay. These sensory changes likely play a causally relevant role in determining high-level alterations and therapeutic outcomes, suggesting that reevaluating sensory dimensions in psychedelic states is valuable for neuroscience and clinical practice.
bioRxiv (Cold Spring Harbor Laboratory)
February 8, 2025
Marco Aqil, Gilles de Hollander, Nina Vreugdenhil et al.
1 citation
preprint
Psilocybin changes how the brain processes visual context, altering perception of the Ebbinghaus illusion and reducing contextual modulation in cortical responses. A computational model links these perceptual and neural changes, suggesting that psychedelics may act by disrupting contextual computations throughout the brain.
The Journal of neuroscience : the official journal of the Society for Neuroscience
November 24, 2025
Mona Irrmischer, Marco Aqil, Lisa Luan et al.
A psychedelic substance (DMT) shifts brain oscillations away from criticality—a state of balanced, complex activity—toward a quieter subcritical regime, particularly in alpha and adjacent frequency bands. This shift increases entropy while reducing complexity. The magnitude of the criticality shift in alpha and theta bands correlates with the intensity of self-dissolution, a core feature of the psychedelic experience. These findings suggest that altered proximity to critical dynamics underlies both the neurological and experiential effects of psychedelics, with implications for understanding altered states of consciousness.
Nature communications
November 21, 2025
Marco Aqil, Gilles De Hollander, Nina Vreugdenhil et al.
Psilocybin changes how the brain processes visual context, altering perception of the Ebbinghaus illusion and modifying cortical responses to visual stimuli. A computational model links these changes, suggesting that psychedelics generally act by disrupting contextual computations in the brain.
October 16, 2024
Marco Aqil
A visual-spatial population receptive field model based on divisive normalization, a candidate canonical neural computation, unifies and outperforms existing models through local variations in its algorithmic parameters. Model parameter estimates relate to density maps of serotonin and GABA receptors. Administering psilocybin, a serotonin receptor agonist, systematically alters normalization, particularly the parameter relevant for suppression in center-surround configurations. These findings provide direct causal evidence that neurotransmitter receptors are involved in visual computations in the living human brain, bringing together vision science, chemoarchitecture, and neuropharmacology.