Gregory

• Gregory's constructivist theory of perception

  A top down theory of perception, suggesting perception is an active process driven by cognition. Sensory information is combined with stored knowledge about the world, constructing our perception.
• Inferences from visual cues

  • Sensory information is often incomplete, so assumptions (inferences) are made about an object, such as its distance and motion.
  • We base inferences on past experiences with similar objects, and visual cues such as linear perspective and height in plane.
• Model of reality


  Created in the mind based on the combination of our sense impressions and inferences, this is what we perceive and can be different to reality.
• Nurture


  As inferences develop due stored knowledge, based on experience of the world the same sensory information could be interpreted by two people differently due to their experiences. This can include people with cultural differences or of different ages perceiving the world very differently.
• Visual illusions


  • Müller-Lyer, Necker Cube
  • Used by Gregory to demonstrate how our perception is actively constructed.
• Perception is altered by factors such as motivation, expectation, culture and emotion


  Suggests perception is actively constructed as suggested by Gregory
• Gregory's theories

  • Challenged by direct perception theories that show the eyes are capable of detecting the world accurately without the need for inference
• Gregory's constructivist theory

  • Able to explain how visual illusions work, people are fooled by applying their expectations from 3D space on to 2D images
• Evidence from visual illusions is limited to highly manipulated images, and may not apply to how perception works in every day life