top-down processing

use information acquired through experience to make sense of sensory information - contrasted with bottom-up processing which uses information present in the sensory stimulus
Gregory's constructivist theory of perception emphasises importance of top-down processing - while sensory information is the basis for perception it is not in itself sufficient
1. use existing knowledge to form perceptual hypotheses which are then checked against sensory data - supported with visual illusions e.g. Muller-Lyer - adjusted through size constancy
  1. support from tests with Bete people live in jungle with no corners show little susceptibity to illusion
  2. illusion explained in terms of what is in the stimulus - suggested perceptual compromise between actual line length and figure it is a part of
importance is challenged by Gibson's theory of direct perception
important because it integrates top-down and bottom-up processing in a theory of perception
criticized for over-estimating role of top-down processing and underestimating richness of sensory data

Resource summary

	Created by db56hse about 11 years ago