Psychology - Visual Illusions

• Sensation


  The detection of information about the world outside of our brain
• Perception


  The processing, organization and interpretation of the detected information by the brain to make sense of it
• Visual illusions


  • Take advantage of the brain's assumptions from limited visual information
  • Misinterpret depth cues
  • Cause ambiguity where there is no correct way to perceive the image
  • Create a perception of something not actually detected by the senses
• Size consistency


  The brain's assumption that far away objects are smaller than closer ones based on experience
• Monocular depth cues


  Visual cues that can be perceived with one eye, such as height in a plane, relative size, occlusion, and linear perspective
• Binocular depth cues


  Visual cues that require two eyes, such as the eyes' convergence and the slightly different images from each eye
• The brain merges the slightly different images from each eye to judge distance
• Visual illusions demonstrate that the brain's perception of the world is based on assumptions from limited visual information
• The Ponzo, Muller-Lyer and Ames room demonstrate misinterpreted depth cues
• Rubin's vase and the Necker cube are examples of ambiguous visual illusions
• The Kanizsa triangle is an example of a visual illusion that creates a perception of something not actually detected by the senses