Perceptual illusions in brief visual presentations

Conscious Cogn. 2009 Sep;18(3):569-77. doi: 10.1016/j.concog.2009.03.002. Epub 2009 Apr 14.

Abstract

We often feel that our perceptual experience is richer than what we can express. For instance, when flashed with a large set of letters, we feel that we can see them all, while we can report only a few. However, the nature of this subjective impression remains highly debated: while many favour a dissociation between two forms of consciousness (access vs. phenomenal consciousness), others contend that the richness of phenomenal experience is a mere illusion. Here we addressed this question with a classical partial-report paradigm now modified to include unexpected items in the unreported parts of the stimuli. We show that even in the presence of unexpected pseudo-letters, participants still felt that there were only letters. Additionally, we show that this feeling reflects an illusion whereby participants reconstruct letters using partial letter-like information. We propose that the feeling of seeing emerges from the interplay between partially accessible information and expectations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Attention*
  • Awareness
  • Cues
  • Discrimination, Psychological
  • Female
  • Humans
  • Judgment
  • Male
  • Memory, Short-Term
  • Optical Illusions*
  • Pattern Recognition, Visual*
  • Perceptual Closure
  • Reaction Time*
  • Young Adult