1. Perception

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

3. Selective Attention
Perceptions about objects change from moment to moment. We can perceive different forms of the Necker cube; however, we can only pay attention to one aspect of the object at a time.
OBJECTIVE 1| Describe the interplay between attention and perception.
Necker Cube

4. Inattentional Blindness

5. Inattentional Blindness
Inattentional blindness refers to the inability to see an object or a person in our midst. Simmons & Chabris (1999) showed that half of the observers failed to see the gorilla-suited assistant in a ball passing game.
Daniel Simons, University of Illinois

6. Change Blindness
Change Blindness 2
Change Blindness 3
Color Change Card Trick

7. Change Blindness
Change blindness is a form of inattentional blindness in which two-thirds of individuals giving directions failed to notice a change in the individual asking for directions.
© 1998 Psychonomic Society Inc. Image provided courtesy of Daniel J. Simmons.

8. Perceptual Organization
When vision competes with our other senses, vision usually wins – a phenomena called visual capture.
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.
OBJECTIVE 3| Describe Gestalt psychology's contribution to our understanding of perception.

9. Gestalt Principles
Proximity: when we see a number of similar objects, we tend to perceive them as groups or sets
Similarity: When similar and dissimilar objects are mingled, we see the similar objects as groups

10. Gestalt Principles
Continuity: we tend to see continuous patterns, not disrupted ones
Simplicity: We see the simplest shapes possible
Closure: when we see a familiar pattern or shape with some missing parts, we fill in the gaps

12. Form (Figure-GRound) Perception
Organization of the visual field into objects (figures) that stand out from their surroundings (ground).
OBJECTIVE 4| Explain the figure-ground relationship and identify principles of perceptual grouping in form perception.
Time Savings Suggestion, © 2003 Roger Sheperd.

13. Figure-Ground Perception
Figure-Ground perception is important to hearing as well as vision.
Example: Listening to one voice in a noisy, crowded room.

14. Color Blindness
Genetic disorder in which people are blind to green or red colors. This supports the Trichromatic theory.
Ishihara Test

15. Visual Information Processing
Opponent-Process Theory- opposing retinal processes enable color vision
“ON” “OFF”
red green
green red
blue yellow
yellow blue
black white white black

16. Opponent Colors Gaze at the middle of the flag for about 30
seconds. When it disappears, stare at the dot and report
whether or not you see Britain's flag.