1. Drill
1.  The Amplitude of electromagnetic waves determines the ________of light
Absolute Threshold
Brightness
Hue
Difference Threshold
Wavelength 
2. Which theory best explains how we perceive low-pitched sounds?
Place Theory
Opponent – Process Theory
Frequency Theory
Young-Helmholtz Theory
Gate-control Theory 

2. Unit 5: Sensation, Perception and States of Consciousness
NHHS AP Psychology
Unit 5: Sensation, Perception and States of Consciousness
Essential Task 5-5:  Describe general principles of perception/ top down processing (organizing and integrating sensation) that promote stable awareness of the external world with specific attention to the Gestalt principles of figure/ground, closure, proximity, connectedness, similarity and the mono and binocular cues for depth perception).
Logo Green is R=8 G=138 B= Blue is R= 0 G=110 B=184
Border Grey is R=74 G=69 B=64

3. Perceptual Constancies
Sensation
Vision
The Eye
Theories
Hearing
The Ear
Other Senses
Smell
Taste
Pain
Gestalt Principles
Perceptual Constancies
Perception
Basic Principles
Visual Illusions
Depth Perception
We are here

4. Constructing the Visual World
Bottom Up & Top Down Processing
Form perception
Depth and distance perception
Visual constancies: When seeing is believing
Visual illusions: When seeing is misleading

5. Digesting raw sensory information to make sense of something.
Why did we see different things?
Bottom Up processing
Digesting raw sensory information to make sense of something.  
Our feelings of pain combine both top down & bottom up processing.  (tickling) 
Top Down processing 
You go beyond the sensory information to try to make meaning out of ambiguity in your world
What you expect (your experiences and your perceptual set) drives this process 

6. What do you see??

7. Group A
You are going to look briefly at a picture and then answer some questions about it. The picture is a rough sketch of a poster for a costume ball (formal dance). Do not dwell on the picture. Look at it only long enough to “take it all in” once. After this, you will answer YES or NO to a series of questions.
lkddjkfjkfdf

9. Group B
You are going to look briefly at a picture and then answer some questions about it. The picture is a rough sketch of a poster for a trained seal act. Do not dwell on the picture. Look at it only long enough to “take it all in” once. After this, you will answer YES or NO to a series of questions.

11. Picture

12. In the picture was there . .
A car?
A man?
A woman?
A child?
An animal?
A whip?
A cane?
A fancy dress?
A beach ball?
A fish?

13. How old is the woman on the following slide?
Without speaking, write your answer on a piece of paper.

14. How old is this person?
Another look...

15. Perceptual Ambiguity
Your brain tries to make sense of what you are looking at based on the region you are focusing on.

16. Gestalt-
See the whole picture, not just the parts

17. Figure-Ground
To recognize an object (figure) we must first perceive it as distinct from its surroundings. (ground)

18. Examples of figure-ground

19. Figure-ground examples

20. Form Perception – Gestalt
Sensation & Perception *
Form Perception – Gestalt
Gestalt principles describe the brain’s organization of sensory building blocks into meaningful units and patterns.
Proximity
Similarity
Closure
Continuation
Figure 3.24 from:
Kassin, S. (1998). Psychology, second edition. Upper Saddle River, NJ: Prentice Hall.
©1999 Prentice Hall 20

21. explanation...

22. Proximity
Proximity occurs when elements are placed close together. They tend to be perceived as a group.
The fifteen figures above form a unified whole (the shape of a tree) because of their proximity.
Reading

24. Similarity
Similarity occurs when objects look similar to one another. People often perceive them as a group or pattern.

25. Similarity

26. Closure
Closure occurs when an object is incomplete or a space is not completely enclosed. If enough of the shape is indicated, people perceive the whole by filling in the missing information.
Although the panda is not complete, enough is present for the eye to complete the shape. When the viewer's perception completes a shape, closure occurs.

27. Continuation
Continuation occurs when the eye is compelled to move through one object and continue to another object.
Viewer's eye will naturally follow a line or curve. The smooth flowing crossbar of the "H" leads the eye directly to the maple leaf.

28. Proximity and Closure

29. Gestalt Principles Gone Awry
Objects located within very little distance of one another. become related as a group, even if they are dissimilar in almost every way--in form, texture, value, or color.
Sign is read from top to bottom because of the how the words are arranged in columns. If read as a column, the words do not make sense, but if read the correct way, the sign tells us something important.

30. Poorly placed dollar sign…

31. Gestalt Principles Proximity Similarity Continuity Closure
Sensation & Perception *
Gestalt Principles
Proximity
Seeing 3 pair of lines in A.
Similarity
Seeing columns of orange and red dots in B.
Continuity
Seeing lines that connect 1 to 2 and 3 to 4 in C.
Closure
Seeing a horse in D.
Figure 3.25 from:
Kassin, S. (1998). Psychology, second edition. Upper Saddle River, NJ: Prentice Hall.
©1999 Prentice Hall 31

32. Depth and Distance Perception- vid clip
Binocular Cues:
Visual cues to depth or distance that require the use of both eyes.
Convergence: Turning inward of the eyes, which occurs when they focus on a nearby object.
Retinal Disparity: The slight difference in lateral separation between two objects as seen by the left eye and the right eye.

33. Depth Perception
Depth perception enables us to judge distances. Gibson and Walk (1960) suggested that human infants (crawling age) have depth perception. Even newborn animals show depth perception.
OBJECTIVE 5| Explain the importance of depth perception, and discuss the contribution of visual cliff research to our understanding of this ability.
Visual Cliff

34. Binocular Cues: Retinal Disparity
Retinal disparity: Images from the two eyes differ.
While focusing far away try touching your fingers about 5 inches directly in front of your eyes. You will see a “finger sausage”
The amount of disparity (difference) between the two images can be used as a cue for distance
Try holding up two fingers one in front of the other. Focus on the front one (you should now see two images of the back one). Now move the back one away from, then back towards you, while still focusing on the front one.

35. Binocular Cues: Convergence
Convergence: Neuromuscular cues. When two eyes move inward (towards the nose) to see near objects and outward (away from the nose) to see faraway objects.
OBJECTIVE 6| Describe two binocular cues for perceiving depth, and explain how they help the brain to compute distance.

36. Depth and Distance Perception
Monocular Cues:
Visual cues to depth or distance that can be used by one eye alone.
Horizontal-vertical illusion (perceiving vertical dimensions as longer than horizontal

37. Monocular Cues
Relative Size: If two objects are similar in size, we perceive the one that casts a smaller retinal image to be farther away.
OBJECTIVE 7| Explain how monocular cues differ from binocular cues, and describe several monocular cues for perceiving depth.

38. Monocular Cues
Interposition: Objects that occlude (block) other objects tend to be perceived as closer.

39. Monocular Cues
Relative Clarity: Because light from distant objects passes through more light than closer objects, we perceive hazy objects to be farther away than those objects that appear sharp and clear.

40. Monocular Cues
Linear Perspective: Parallel lines, such as railroad tracks, appear to converge in the distance. The more the lines converge, the greater their perceived distance.

41. Monocular Cues
Texture Gradient: Closer objects tend to have a courser texture than to far way objects

42. Monocular Cues
Relative motion: Objects closer to a fixation point move faster and in opposing direction to those objects that are farther away from a fixation point, moving slower and in the same direction.

43. Monocular Cues
Light and Shadow: Nearby objects reflect more light into our eyes than more distant objects. Given two identical objects, the ones that are shaded on top are seen as “sticking out toward us”

44. The Ames Room- vid clip
A specially-built room that makes people seem to change size as they move around in it
The room is not a rectangle, as viewers assume it is
A single peephole prevents using binocular depth cues

45. Perceptual Constancies
The accurate perception of objects as stable or unchanged despite changes in the sensory patterns they produce.
Shape constancy
Location constancy
Size constancy
Brightness constancy
Color constancy

46. Sensation & Perception*
Shape Constancy
Even though these images cast shadows of different shapes, we still see the quarter as round
Figure 3.3Davis 2 from:
Kassin, S. (1998). Psychology, second edition. Upper Saddle River, NJ: Prentice Hall.
©1999 Prentice Hall 46

47. Color Constancy
Color remains constant even when lighting and wavelengths shift.
It demonstrates that our experience of color comes not only from the object, but everything around it as well.

48. Visual Illusions
Illusions are valuable in understanding perception because they are systematic errors.
Illusions provide hints about perceptual strategies.
In the Muller-Lyer illusion (above) we tend to perceive the line on the right as slightly longer than the one on the left.

49. The Ponzo Illusion Linear perspective provides context
Side lines seem to converge
Top line seems farther away
But the retinal images of the red lines are equal!

50. Perception of Movement
Stroboscopic motion
Created by a rapid series of still pictures
Phi phenomenon
Apparent motion created by lights flashing in sequence