Perception 1 Perception The process of selecting organizing

Perception 1

Perception The process of selecting, organizing, and interpreting sensory information, which enables us to recognize meaningful objects and events. 2

Selective Attention Perceptions about objects change from moment to moment. We can only focus on limited aspects of sensory input at any given time e. g. : “Cocktail Party Effect” 3

Perceptual Illusions provide good examples in understanding how perception is organized. Studying faulty perception is as important as studying other perceptual phenomena. Line AB is longer than line BC. 4

Tall Arch Rick Friedman/ Black Star In this picture, the vertical dimension of the arch looks longer than the horizontal dimension. However, both are equal. 5

Perceptual Organization How do we form meaningful perceptions from sensory information? We organize it. Gestalt psychologists showed that a figure formed a “whole” different than its surroundings. called a “gestalt” 6

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Form Perception Organization of the visual field into objects (figures) that stand out from their surroundings (ground). Time Savings Suggestion, © 2003 Roger Sheperd. 8

Perception in Brain n Our perceptions are a combination of sensory (bottom-up) and cognitive (topdown) processes. 9

Perceptual Interpretation Immanuel Kant (1724 -1804) maintained that knowledge comes from our inborn ways of organizing sensory experiences. John Locke (1632 -1704) argued that we learn to perceive the world through our experiences. How important is experience in shaping our perceptual interpretation? 10

Sensory Deprivation Kittens raised without exposure to horizontal lines later had difficulty perceiving horizontal bars. Blakemore & Cooper (1970) 11

Perceptual Set Other examples of perceptual set. Dick Ruhl Frank Searle, photo Adams/ Corbis-Sygma (a) Loch ness monster or a tree trunk; (b) Flying saucers or clouds? 12

Cultural Context instilled by culture also alters perception. To an East African, the woman sitting is balancing a metal box on her head, while the family is sitting under a tree. 13

Perception Revisited Is perception innate or acquired? 14

The following factor(s) affect our detection of weak signals: a. b. c. d. e. motivation fatigue expectations all of the above b & c but not a 15

With respect to sensation and perception, it is fair to say that : a. experience plays no role b. perception does not appear to involve any inborn perceptual capacities c. humans experience external stimuli as they are with little processing by the brain d. none of the above 16