Thinking About Psychology: The Science of Mind and Behavior

1. Thinking About Psychology: The Science of Mind and Behavior Charles T. Blair-Broeker Randal M. Ernst

2. Perception Module 10

3. Perception • The process of organizing and interpreting sensory information • Top Down Processing

4. Perception The process of selecting, organizing, and interpreting sensory information, which enables us to recognize meaningful objects and events (Top down processing).

5. Organizational Principles Module 10: Perception

7. 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. Other examples: the Stroop Task, dichotic listening) Necker Cube

8. SELECTIVE ATTENTION • Stress narrows attention • OTHER EXAMPLES: • Cell phones in car • ?

9. Count the number of times the ball is passed: • http://www.youtube.com/watch?v=vJG698U2Mvo

10. Change Blindness • http://www.youtube.com/watch?v=-HVw9kWkPX0

11. Gestalt • The “whole,” or the organizational patterns that we tend to perceive • Gestalt psychologists stressed that the whole is greater than the sum of its parts. • By breaking experiences into their basic parts, something important is lost.

12. A Gestalt

13. Organizational Principles: Figure-Ground Relationships Module 10: Perception

14. Figure-Ground • The perceptual tendency to organize stimuli into objects (the figures) that stand out from their surrounding (the ground) • The figure is the object(s) that stands out or draws one’s attention. • The ground is the background.

15. Organizational Principles: Grouping Principles Module 10: Perception

16. Grouping • The perceptual tendency to organize stimuli into understandable groups • Several principles of grouping include: • Similarity • Proximity • Closure • Continuity

17. Grouping - Similarity • The tendency to place items that look similar into a group

19. Grouping - Proximity • The tendency to place objects that are physically close to each other in a group

21. Grouping – Closure • The tendency to look at the whole by filling in gaps in a perceptual field

23. Grouping – Continuity • The tendency to perceive that movement of an object continues once it appears to move in a particular direction

25. Depth Perception Module 10: Perception

26. Depth Perception • The ability to see in three dimensions and judge distances

27. Visual Cliff • A laboratory device for testing depth perception in infants and young animals • Infants are reluctant to crawl past the “edge” of the visual cliff • Other animals had similar results. • Suggests that depth perception, to some extend, is inborn

28. Visual Cliff

29. Depth Perception: Binocular Depth Cues Module 10: Perception

30. Binocular Cues • Depth cues that require the use of both eyes

31. Retinal Disparity • A binocular depth cue resulting from slightly different images produced by the separation of the retinas in the left and right eye • Is most effective when the item is quite close to the person

32. Binocular Depth Cues: Finger Sausage

33. Convergence • A binocular depth cue related to the tension in the eye muscles when the eyes track inward to focus on objects close to the viewer • The more tension in the eye muscle, the closer the object is • Works best at close distances

34. Depth Perception: Monocular Depth Cues Module 10: Perception

35. Monocular Cues • Depth cues that require the use of only one eye • Monocular depth cues include: relative size, relative motion, interposition, relative height, texture gradient, relative clarity, and linear perspective.

36. Monocular Depth Cues – Relative Size • Using the perceived size of a familiar object to determine depth • The larger the object appears, the closer the object is to the viewer

37. Monocular Depth Cues – Relative Motion • A person who is moving can determine depth by focusing on a distant object. • Objects further away than the object of focus will appear to move in the same direction as the subject is moving. • Objects closer than the object of focus will appear to move in the opposite direction.

38. Relative Motion

39. Monocular Depth Cues – Interposition • Method of determining depth by noting that closer objects partially obstruct the more distant objects • Also called “overlap”

40. Monocular Depth Cues – Relative Height • Method of determining depth by noting that distant objects appear higher in your field of vision than do closer objects

41. Monocular Depth Cues–Texture Gradient • Method of determining depth by noting that distant objects have a smoother texture than nearby objects

42. Monocular Depth Cues – Relative Clarity • Method of determining depth by noting that distant objects are less clear than nearby objects • Tends to work outdoors

43. Monocular Depth Cues–Linear Perspective • Method of determining depth by noting that parallel lines appear to converge in the distance • The lines appears to eventually merge on the horizon.

44. Motion Perception Module 10: Perception

45. Stroboscopic Motion • The illusion of motion by the rapid projection of slightly changing images • The concept a motion picture uses

46. Phi Phenomenon • The illusion of motion when fixed lights are turned on and off in a sequence

47. Perceptual Constancy Module 10: Perception

48. Perceptual Constancy • Perceiving the size, shape, and lightness of an object as unchanging, even as the retinal image of the object changes • The understanding that objects usually remain the same

49. Perceptual Constancy: Size Constancy Module 10: Perception

50. Size Constancy • A person’s understanding that as an object moves further or closer to them its actual size stays the same • As an object appears to become larger we realize it is getting closer, not bigger. • As an object appears to become smaller we realize it is moving farther away, not getting smaller.