Illusory object recognition is either perceptual or cognitive in origin depending on decision confidence

PLoS Biol. 2023 Mar 2;21(3):e3002009. doi: 10.1371/journal.pbio.3002009. eCollection 2023 Mar.

Abstract

We occasionally misinterpret ambiguous sensory input or report a stimulus when none is presented. It is unknown whether such errors have a sensory origin and reflect true perceptual illusions, or whether they have a more cognitive origin (e.g., are due to guessing), or both. When participants performed an error-prone and challenging face/house discrimination task, multivariate electroencephalography (EEG) analyses revealed that during decision errors (e.g., mistaking a face for a house), sensory stages of visual information processing initially represent the presented stimulus category. Crucially however, when participants were confident in their erroneous decision, so when the illusion was strongest, this neural representation flipped later in time and reflected the incorrectly reported percept. This flip in neural pattern was absent for decisions that were made with low confidence. This work demonstrates that decision confidence arbitrates between perceptual decision errors, which reflect true illusions of perception, and cognitive decision errors, which do not.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cognition
  • Electroencephalography
  • Humans
  • Illusions*
  • Photic Stimulation
  • Visual Perception

Grants and funding

This research was supported by a grant from the H2020 European Research Council (ERC STG 715605 to SVG). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.