1. Perceptual Organization: Depth Perception • Depth Perception • ability to see objects in three dimensions • allows us to judge distance Visual Cliff

2. Depth Perception • Binocular cues – depend on use of two eyes • retinal disparity • images from the two eyes differ • closer the object, the larger the disparity • Finger sausage example • convergence • neuromuscular cue • two eyes move inward for near objects

3. Perceptual Organization: Depth Perception • Monocular Cues – depth cues available to either eye alone • relative size • smaller image is more distant • interposition • closer object blocks distant object • relative clarity • hazy object seen as more distant • texture coarse --> close fine --> distant

4. Perceptual Organization: Depth Perception Relative Size

5. Relative Size

6. Relative Size

7. Perceptual Organization: Depth Perception Interposition

9. Perceptual Organization: Depth Perception • Monocular Cues (cont.) • relative height • higher objects seen as more distant • relative motion • closer objects seem to move faster • linear perspective • parallel lines converge with distance • relative brightness • closer objects appear brighter

10. Perceptual Organization: Depth Perception Relative Height

11. Perceptual Organization: Depth Perception Perspective Techniques

12. Perceptual Organization: Depth Perception Light and Shadow

13. In or out?

14. Perceptual Organization: Depth Perception Illusory Depth

15. Perceptual Organization: Depth Perception

16. Phi Phenomenon – illusion of movement created when two or more adjacent lights blink on and off in quick succession • How do movies work?

17. Perceptual Constancy • Perceptual Constancy • perceiving objects as unchanging even as illumination and retinal image change • color • shape • size

18. Perceptual Organization

19. Perceptual Organization: Depth Perception Illusory Depth Explanation

20. Perceptual Organization: Muller-Lyer Illusion Cultural Experiences affects susceptibility to the Muller-Lyer illusion!

21. Perceptual Organization: Size-Distance Relationship

22. Perceptual Organization-Brightness Contrast

23. Perceptual Organization-Brightness Contrast

24. Perceptual Organization: Grouping Principles • Impossible doghouse

25. Sensory Restriction:Blakemore & Cooper, 1970 • Kittens raised without exposure to horizontal lines later had difficulty perceiving horizontal bars.