Theories of perception and perceptual set · GCSE Psychology

Gibson's direct theory

Gibson argued that perception is direct and bottom-up: the information in the environment is rich enough for us to perceive without needing past experience.
Motion parallax: as we move, nearer objects seem to pass quickly and further ones slowly, giving depth information.
Evaluation: it explains how we perceive quickly in real life and why babies can perceive depth early, but it can't explain visual illusions.

Gregory argued that perception is indirect and top-down: we use past experience and knowledge to make inferences about what we see.
Visual illusions happen because we make wrong inferences, such as misapplying depth cues.
Evaluation: it explains illusions and cultural differences, but it can't fully explain how perception works so quickly and accurately, and depends on experiences babies don't yet have.

Perceptual set is a readiness to perceive things in a certain way. It is affected by expectation, motivation, emotion and culture.
Expectation: Bruner and Minturn showed an ambiguous figure that could be read as "B" or "13". People saw it as B among letters and as 13 among numbers.
Motivation: Gilchrist and Nesberg found that hungry participants rated pictures of food as brighter than people who weren't hungry.
Culture: Hudson found that people from some cultures interpreted depth cues in pictures differently, suggesting culture affects perception.

Direct theory: Gibson's idea that perception comes directly from the environment (bottom-up).
Constructivist theory: Gregory's idea that perception uses past experience to make inferences (top-down).
Perceptual set: A readiness to perceive things in a particular way.
Motion parallax: Nearer objects seeming to move faster than further ones as we move.
Inference: A conclusion drawn from evidence and experience.
Top-down processing: Perception guided by knowledge and expectation.
Bottom-up processing: Perception built from sensory information alone.