The moon size illusion does not improve perceptual judgments

Conscious Cogn. 2019 Aug:73:102754. doi: 10.1016/j.concog.2019.05.002. Epub 2019 May 31.

Abstract

Recent studies suggest that the accuracy of perceptual judgments can be influenced by the perceived illusory size of a stimulus, with judgments being more accurate for increased illusory size. This phenomenon seems consistent with recent neuroscientific findings that representations in early visual areas reflect the perceived (illusory) size of stimuli rather than the physical size. We further explored this idea with the moon illusion, in which the moon appears larger when it is close to the horizon and smaller when it is higher in the sky. Participants (n=230) adjusted the orientation of an image of the moon on a smartphone to match the perceived orientation of the moon in the sky. Contrary to previous studies that investigated accuracy and size illusions, we found slightly lower perceptual judgment accuracy when the moon appeared large (close to the horizon) compared to when it appeared small (high in the sky).

Keywords: Illusions; Moon; Orientation; Size.

MeSH terms

  • Adult
  • Female
  • Humans
  • Illusions / physiology*
  • Judgment / physiology
  • Male
  • Moon*
  • Optical Illusions / physiology*
  • Size Perception / physiology*
  • Visual Perception / physiology*
  • Young Adult