1. CHAPTER 3: Sensation and Perception
Sensation & Perception
4/16/2017
Psychology, 4/e by Saul Kassin
Prepared by Michael J. Renner, Ph.D.
These slides ©2001 Prentice Hall Psychology Publishing.
CHAPTER 3: Sensation and Perception
©2001 Prentice Hall

2. Sensation and Perception
Sensation & Perception
4/16/2017
Sensation and Perception
Measuring the Sensory Experience
Sensation
Perception
Extrasensory Perception
Chapter outline
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

3. Sensation and Perception
Sensation & Perception
4/16/2017
Sensation and Perception
Sensation
The processes by which our sense organs receive information from the environment.
Transduction
The process by which physical energy is converted into sensory neural impulses.
Perception
The processes by which people select, organize, and interpret sensations.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

4. Sensation & Perception
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Sensation & Perception Processes
Figure 3.2 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

5. Sensation & Perception
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Measuring Sensory Experience Research and Theory
Psychophysics
The study of the relationship between physical stimulation and subjective sensations.
Signal-Detection Theory
The theory that detecting a stimulus is jointly determined by the signal and the subject’s response criterion.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

6. Sensation & Perception
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Measuring Sensory Experience Thresholds
Absolute Threshold
The smallest amount of stimulation that can be detected.
Just Noticeable Difference (JND)
The smallest amount of change in a stimulus that can be detected.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

7. Sensation & Perception
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Measuring Sensory Experience Absolute Sensory Thresholds
Vision: A single candle flame from 30 miles on a dark, clear night
Hearing: The tick of a watch from 20 feet in total quiet
Smell: 1 drop of perfume in a 6-room apartment
Taste: 1 teaspoon sugar in 2 gallons of water
Touch: The wing of a bee on your cheek, dropped from 1 cm
From:
Davis, S., & Palladino, J. (1997). Discovering Psychology.
Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

8. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Sensation
Vision
Hearing
Other Senses
Keeping the Signals Straight
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

9. Sensation & Perception
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Vision
The Electromagnetic Spectrum
Figure 3.3 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

10. Sensation & Perception
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Vision Structures of the Human Eye
Figure 3.4 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Source:
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

11. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Vision Structures of the Human Eye
Cornea
Clear outer membrane that bends light to focus it in the eye.
Pupil
The hole in the iris through which light passes.
Lens
The structure that focuses light on the retina.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

12. Sensation & Perception
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Vision The Retina
The rear of the eye where rods and cones convert light into neural impulses.
Figure 3.5 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

13. Sensation & Perception
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Vision
Visual Pathways
Optic Nerve
Pathway that carries visual information from the eyeball to the brain.
Figure 3.7 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

14. Sensation & Perception
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Vision Hubel & Wiesel’s Experiment
Some cells in the visual cortex respond only to certain types of visual information, for example, a diagonal line moving up and down.
These cells are called feature detectors.
Figure 3.8 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Source:
Hubel, D. H.., & Wiesel, T.N. (196Davis 2). Receptive fields, binocular interaction and functional architecture in the cat’s visual cortex. Journal of Physiology, 160,
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

15. Sensation & Perception
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Vision Trichromatic Theory
T. Young (1802) & H. von Helmholtz (1852) both proposed that the eye detects 3 primary colors: red, blue, & green.
All other colors can be derived by combining these three.
Figure 3.9 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

16. Sensation & Perception
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Vision Afterimage
Figure 3.10 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

18. Sensation & Perception
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Vision The Color Wheel
Spectral colors vary from violet-blue to red
470 to 700 nanometer wavelength
Opponent colors are directly across from each other on the wheel.
Figure 3.11 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

19. Sensation & Perception
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Vision Test of Color Deficiency
Figure 3.12 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

20. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Vision
Opponent-Process Theory
Color vision is derived from three pairs of opposing receptors. The opponent colors are blue and yellow, red and green, and black and white.
Theory explains afterimages and color deficiency.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

21. Sensation & Perception
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Hearing The Human Ear
Audition
The sense of hearing
Figure 3.13 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

22. Sensation & Perception
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Hearing Auditory Localization
The ability to judge from which direction a sound is coming
Sounds from different directions are not identical as they arrive at left and right ears.
The brain calculates a sound’s location by using differences in timing and intensity.
Figure 3.14 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

23. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Hearing Hearing Disabilities
Conduction Hearing Loss
Caused by damage to the eardrum or bones in the middle ear.
Sensorineural Hearing Loss
Caused by damage to the structures of the inner ear.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

24. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Hearing Common Sounds and the Noise They Produce
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

25. Sensation & Perception
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Other Senses Olfactory System
Structures responsible for the sense of smell
Figure 3.16 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

26. Sensation & Perception
4/16/2017
Other Senses Taste Buds
Nets of taste-receptor cells
This is a photograph of tongue surface (top), magnified 75 times.
10,000 taste buds line the tongue and mouth.
Children have more taste buds than adults do.
There are four primary tastes: sweet, salty, sour, and bitter.
Figure 3.17 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

27. Sensation & Perception
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Other Senses
Sensitivity to Touch
Figure 3.18 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

28. Sensation & Perception
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Other Senses The Thermal Grill
Temperature
When a person grasps two braided water pipes – one with cold water running through it and one with warm water – the sensation is “burning hot” and painful.
There are two separate pathways for warmth and cold.
Figure 3.19 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

29. Sensation & Perception
4/16/2017
Other Senses
Pain
Gate-control Theory
Theory that the spinal cord contains a neurological “gate”that blocks pain signals for the brain when flooded by competing signals.
Psychological control
Mind over sensation, distraction
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

30. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Other Senses
Coordination
Kinesthetic System
Structures distributed throughout body that sense position and movement of body parts.
Vestibular System
The inner ear and brain structures that afford a sense of equilibrium.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

31. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Keeping the Signals Straight
Synesthesia
Rare condition in which stimulation in one sensory modality triggers sensations in another sensory modality.
Each sensory system designed to operate separately from the others.
Selective Adaptation
A decline in sensitivity to a stimulus as a result of constant exposure.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

32. Sensation & Perception
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Perception
Perceptual Organization
Perceptual Constancies
Depth and Dimension
Perceptual Set
The World of Illusions
Section outline
©2001 Prentice Hall

33. Sensation & Perception
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Perceptual Organization Reversible Figures
Drawings that one can perceive in different ways by reversing figure and ground.
Gestalt Psychology
School of thought rooted in the idea that the whole is different from the sum of its parts.
Figure 3.20 (lady/girl) and 3.21 (rabbit/duck) from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Quote from:
Shephard, R. N. (1990). Mind Sights. New York: W. H. Freeman.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

34. Sensation & Perception
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Perceptual Organization Gestalt Laws of Grouping
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 3.23 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

35. Sensation & Perception
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Perceptual Organization Identifying Objects
Geons (geometric icons) are simple 3D component shapes.
A limited number are stored in memory.
Geons are combined to identify essential contours of objects.
Figure 3.25 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Source: Biederman, I. (1987). Recognition-by-components: A theory of human image understanding. Psychological Review, 94,
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

36. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Perceptual Constancies
Size Constancy
The tendency to view an object as constant in size despite changes in the size of the retinal image.
Shape Constancy
The tendency to see an object as keeping its form despite changes in orientation.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

37. Perceptual Constancies The Ames Room
Sensation & Perception
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Perceptual Constancies The Ames Room
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.
Figure 3.25 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

38. Sensation & Perception
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Perceptual Constancies Shape Constancy
Figure 3.26 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Even though these images cast shadows of different shapes, they still are seen as round.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

39. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Depth and Dimension
Depth Perception
The use of visual cues to estimate depth and distance.
Convergence
A binocular cue involving the turning inward of the eyes as an object gets closer.
Binocular Disparity
A binocular cue whereby the closer an object is, the more different the image is in each retina.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

40. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
Depth and Dimension Monocular Depth Cues
Distance cues that enable the perception of depth with one eye.
Relative Image Size
Texture Gradient
Linear Perspective
Interposition
Atmospheric Perspective
Relative Elevation
Familiarity
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

41. Sensation & Perception
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Depth and Dimension The Visual Cliff
Devised by Eleanor Gibson and Richard Walk to test depth perception in infants and animals.
Provides visual illusion of a cliff.
Caregiver stands across the gap.
Babies are not afraid until about the age they can crawl.
Figure 3.27 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

42. Sensation & Perception
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Perceptual Set
What is seen in the center figures depends on the order in which one looks at the figures:
If scanned from the left, a man’s face is seen.
If scanned from the right, a woman’s figure is seen.
Figure 3.28 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

43. Sensation & Perception
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Perceptual Set Context Effects
The same physical stimulus can be interpreted differently depending on perceptual set, e.g., context effects.
When is the middle character the letter B and when is it the number 13?
Figure 3.29 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

44. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
The World of Illusions The Müller-Lyer Illusion
Illusion in which the perceived length of a line is altered by the position of other lines that enclose it
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall

45. Sensation & Perception
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The World of Illusions The Ponzo Illusion
Illusion in which the perceived line length is affected by linear perspective cues.
Side lines seem to converge
Top line seems farther away
But the retinal images of the red lines are equal.
Figure 3.32 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

46. Sensation & Perception
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Extrasensory Perception
The Case for ESP
The Case against ESP
The Continuing Controversy
Section outline
©2001 Prentice Hall

47. Sensation & Perception
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The Case for ESP
Extrasensory Perception (ESP)
The ability to perceive something without ordinary sensory information.
This has not been scientifically demonstrated.
Parapsychologists distinguish between three types of ESP:
Telepathy – Mind-to-mind communication
Clairvoyance – Perception of remote events
Precognition – Ability to see future events
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

48. Sensation & Perception
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The Case against ESP ESP Cards
J. B. Rhine conducted many experiments on ESP using stimuli such as these.
Rhine believed that his evidence supported the existence of ESP, but his findings were flawed..
Figure 3.33 from:
Kassin, S. (2001). Psychology, third edition. Upper Saddle River, NJ: Prentice Hall.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
©2001 Prentice Hall

49. Psychology, 4/e by Saul Kassin ©2004 Prentice Hall
The Continuing Controversy
The ganzfield procedure
Researchers disagree about the reliability of studies done to replicate the ganzfield test.
Visit for information about the James Randi Educational Foundation’s million-dollar paranormal challenge.
Psychology, 4/e by Saul Kassin ©2004 Prentice Hall