Perceptual Interpretation Chapter 6, Lecture 6 “The river of perception is fed by sensation, cognition, and emotion.” - David Myers

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

Sensory Deprivation & Restored Vision After cataract surgery, blind adults were able to regain sight. These individuals could differentiate figure and ground relationships, yet they had difficulty distinguishing a circle and a triangle (Von Senden, 1932).

Facial Recognition After blind adults regained sight, they were able to recognize distinct features, but were unable to recognize faces. Normal observers also show difficulty in facial recognition when the lower half of the pictures are changed. Courtesy of Richard LeGrand

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

Perceptual Adaptation Visual ability to adjust to an artificially displaced visual field, e.g., prism glasses. Courtesy of Hubert Dolezal Let’s watch a video clip of this phenomenon…

Perceptual Set A mental predisposition to perceive one thing and not another. What you see in the center picture is influenced by flanking pictures. From Shepard, 1990.

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

Is the “magician cabinet” on the floor or hanging from the ceiling? Context Effects Context can radically alter perception.

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

Perception Revisited Is perception innate or acquired?

Perception Revisited Is perception innate or acquired? “Once we have formed a wrong idea about reality, we have more difficulty seeing the truth.” - David Myers

Perception and the Human Factor Human Factors Psychology: a branch of psychology that explores how people and machines interact and how machines and physical environments can be made safe and easy to use.

Homework AY Questions – p.245, 281 (10 pts) Read p “Does the effect of early experience last a lifetime? For some aspects of visual and auditory perception, the answer is clearly yes: ‘Use it soon or lose it.’ We retain the imprint of early sensory experiences far into the future.” - David Myers