Psilocybin alters visual contextual computations

bioRxiv – February 06, 2025

Source: medRxiv/bioRxiv/arXiv

Summary

Psilocybin, a compound found in certain mushrooms, significantly influences how we perceive visual contexts. Using advanced imaging and modeling techniques, researchers demonstrated that it modifies our perception of illusions and alters brain responses to visual stimuli. These findings suggest a broader mechanism for how psychedelics affect our perception.

Abstract

Psilocybin alters perception and brain dynamics. Contextual computations are ubiquitous in the brain. Here, we investigate the effects of psilocybin using psychophysics, ultra-high field functional MRI, and computational modeling. We find that 1) psilocybin alters contextual perception in the Ebbinghaus illusion, 2) psilocybin alters contextual modulation in cortical responses to visual stimuli, and 3) we propose a computational model capable of capturing and linking these changes. Leveraging vision as a beachhead, our findings highlight the alteration of contextual computations as a potential general mechanism underlying psychedelic action.