Psilocybin alters visual contextual computations
OpenAlex – February 08, 2025
Source: OpenAlex
Summary
Psilocybin, a powerful hallucinogen, fundamentally alters visual perception by reshaping how the brain processes context. Insights from cognitive psychology and neuroscience reveal it significantly changes how we perceive illusions, like the Ebbinghaus. Through advanced functional MRI and a sophisticated computational model from computer science, it's shown psilocybin influences neurotransmitter receptor activity, altering contextual brain responses. This work in psychology and psychedelics and drug studies suggests a core mechanism for how this drug impacts perception, offering new understanding of altered states, including those sometimes interpreted as paranormal experiences.
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. Teaser Psilocybin alters visual-contextual computations, a potential general computational mechanism for psychedelic effects in the human brain.