Perception

1. Perception “Beauty is in the eye of the beholder”

2. Gestalt- "The whole is more than the sum of its parts." • Organizing bits and pieces of information into whole parts • We tend to finish uncompleted shapes, group similar items, and can distinguish between foreground and background on a flat piece of paper.     • Proximity • Similarity • Closure • Continuity • Simplicity

3. Proximity- grouping things that are close together • Perceiving objects in “sets” based on their location and distance from one another • In music we hear a melody, rather than just separate notes

4. Similarity- grouping objects that are similar in appearance • Things which share visual characteristics such as shape, size, color, texture, value or orientation will be seen as belonging together.

5. Closure- filling in the gaps of familiar shapes • We tend to enclose incomplete images/pictures to create a true form

6. Continuity- looking for a continuous pattern rather than a disrupted one • Continuity: Every visual unit tends to be continued in the same direction and with the same movement. We have a preference for continuous figures. (In the example, rather than seeing 4 separate line segments, we tend to see 2 intersecting lines)

7. Simplicity- recognizing the most simple shape possible • We tend to see things in the most organized manner • Simplicity: People tend to perceive forms as simple, symmetrical figures rather than as irregular ones. This figure is generally seen as one triangle superimposed on another rather than a triangle with an angular piece attached to it.

8. Figure/Ground perception • Ability to distinguish between a figure and it’s background, 2 dimensional images give us problems with this.

9. Perceptual Interference • Our ability to fill in the gaps to what our senses tell us and what we actually see, hear, taste, smell or touch • Barking-dog • Dark theater- seat holds you • Road disappears up a hill- actually there • Depends on experience, knowing what to expect “Perceptual Set”

10. Subliminal advertising • Just below the absolute threshold, or conscious awareness. • The main influence that subliminally perceived items can have on you is to increase the accessibility of concepts relating to those items. • No evidence to support it has an effect on behavior

11. Depth Perception- ability to recognize distance and 3 dimensionality • Monocular clues • Binocular clues • Develops in infants (visual cliff)

12. Monocular Depth Perception- related to one eye • Occlusion: • Farther objects are being occluded by nearer objects. • Perspective: • Objects of the same size are bigger if they are nearer to the viewer. • Depth of field: • Adaption of the eye lens warping, so called accomodation, focuses objects in a specific distance to the viewer. Other objects with a different distance to the viewer appear blurred. • Movement parallax: • If objects with a different distance to the viewer move with the same speed, nearer objects appear to be faster than farther objects.

13. Monocular Depth perception • Occlusion Perspective Depth of field Movement parallax

14. Binocular Depth cues • Each of our eyes sees a slightly different image of the world- separate camera, sees environment from different position. • Convergence: The distance between our eyes is fixed but the angle depends on the distance of a focused object. If we watch the clouds in the sky the eye orientation is nearly the same but when we look at a fly which sits on our nose, the left eye looks more to the right and the right eye to the left, so we are squinting. This angle between the optical axes of both eyes, the convergence, gives our brain a hint about the distance to an object.

15. Retinal Disparity • Pupils of eyes are about 3 inches apart • Right eye gives a slightly different view than left eye • The difference between the two images projected on the retina is the retinal disparity, a cue for depth • We actually see both images, we only perceive on in our brain

16. Retinal disparity

17. Constancy • The ability to perceive objects as the same regardless of the changes in the physical environment, like angle, distance or lighting • Size constancy –friend walking near • Distance decreases as size increases

18. Size Constancy

19. Illusions- incorrect perception • Perceptual cues are distorted so our brain can not correctly interpret space, size and depth cues • Our brain might treat an object as 3D when it is actually 2D, creating an illusion