1. Unit 4: Sensation and Perception

2. Sensing the World: Some Basic Principles

3. Introduction Sensation: Perception: continuous process, two components
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
Perception:
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
continuous process, two components

4. Introduction
Bottom-up processing
Top-down processing

5. Selective Attention selective attention
the focusing of conscious awareness on a particular stimulus
cocktail party effect

6. Selective Attention Selective Attention and Accidents
cell phone use and car accidents

7. Selective Attention Selective Inattention
inattentional blindness
failing to see visible objects when our attention is directed elsewhere

8. Selective Attention Selective Inattention
change blindness
failure to notice changes in the environment
change deafness
choice blindness
choice-choice blindness
pop-out

9. Thresholds Absolute Thresholds
50 % of the time

10. Thresholds Signal Detection
signal-detection theory
predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise)
assumes there is no single absolute threshold
detection depends partly on a person’s experience, expectations, motivation and alertness
ratio of “hits” to “false alarms”

11. Thresholds Subliminal Stimulation
subliminal (below threshold)
priming
masking stimulus
subliminal persuasion

12. Thresholds Difference Thresholds
the minimum difference between 2 stimuli required for detection 50% of the time
just noticeable difference (jnd)
Weber’s Law
to be perceived as different, 2 stimuli must differ by a constant proportion/percentage rather than a constant amount

13. Sensory Adaptation Sensory Adaptation
diminished sensitivity as a consequence of constant stimulation
informative changes
reality versus usefulness

14. Vision

15. The Stimulus Input: Light Energy
transduction (transform)
wavelength
hue (color)
intensity
wave amplitude

16. Electromagnetic Energy Spectrum

17. The Physical Property of Waves

18. The Eye
cornea
pupil
iris
lens
accommodation
retina

19. The Structure of the Eye
Retina = the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information.

20. The Eye The Retina
Rods and Cones
Rods
Cones

21. Rods versus Cones

22. The Retina’s Reaction to Light

23. The Eye The Retina
Optic nerve
Blind spot
Fovea

24. The Structure of the Eye
Blind Spot = the point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there.

25. The Structure of the Eye
Fovea = the central focal point in the retina, around which the eye’s cones cluster.

26. The Structure of the Eye
Optic Nerve = the nerve that carries neural impulses from the eye to the brain.

27. Pathways from the eyes to the visual cortex

28. Visual Information Processing Feature Detection
Feature detectors

29. Visual Information Processing Parallel Processing
blind sight

30. Visual information processing

31. Color Vision Young-Helmholtz trichromatic (three color) theory
red – green - blue
monochromatic vision
dichromatic vision

32. Color Vision Opponent-process theory three sets of colors afterimage
red-green
blue-yellow
black-white
afterimage

33. After image

34. This slide is intentionally left blank.

35. Hearing

36. The Stimulus Input: Sound Waves
audition
amplitude
loudness
frequency
pitch

37. The Ear
Outer ear
Auditory canal
Ear drum

38. The structure of the ear
Eardrum = tight membrane that vibrates when struck by sound waves.

39. The structure of the ear
Eardrum

40. The Ear
Middle ear
Hammer, anvil, stirrup

41. The structure of the ear
Stirrup

42. The structure of the ear
Cochlea = a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses.

43. The Ear inner ear oval window cochlea auditory nerve auditory cortex
basilar membrane
auditory nerve
auditory cortex

44. The structure of the ear
Hair cells in the cochlea

45. The structure of the ear
Auditory nerve = nerve which sends the auditory message to the brain via the thalamus.

46. The structure of the ear
Nerve fibers

47. Neural impulse to the brain

48. The Ear Perceiving Loudness
basilar membrane’s hair cells
compressed sound

49. Cochlea and loud sounds

50. The Ear Perceiving Pitch
Place theory
high pitched sounds
Frequency theory
low pitched sounds
volley principle

51. The Ear Locating Sounds
Stereophonic hearing
Localization of sounds
intensity
speed of the sound

52. Hearing Loss and Deaf Culture
conduction hearing loss
sensorineural hearing loss
cochlea implant
signing

53. Other Senses

54. Touch
Types of touch
pressure
warmth
cold
pain
sensation of hot

55. Touch kinesthesis vestibular sense
the system for sensing the position and movement of individual body parts
vestibular sense
the sense of body movement and position, including the sense of balance
semicircular canals

56. Semicircular Canals

57. Pain Understanding Pain
biological Influences
nociceptors
gate-control theory
endorphins
phantom limb sensations
tinnitus

58. The pain circuit

59. Pain Understanding Pain
psychological Influences
rubber-hand illusion
memories of pain

60. Pain Understanding Pain
social-cultural influences

61. Biopsychosocial approach to pain

62. Pain Controlling Pain
physical methods
psychological methods

63. Taste sweet, sour, salty and bitter taste buds age and taste umami
chemical sense
age and taste

64. Taste Sensory Interaction
interaction of smell and taste
McGurk Effect
interaction of other senses
synasthesia: one stype of sensation producing another (sound/color)

65. Smell Olfaction chemical sense odor molecules olfactory bulb
olfactory nerve

66. Smell (olfaction)

67. Smell and age

68. Perceptual Organization

69. Introduction
Gestalt (form or whole)

70. Form Perception Figure and Ground
Figure-ground
the organization of visual field into objects (the figures) that stand out from their surroundings (the ground)

73. Form Perception Grouping
proximity
similarity
continuity
connectedness
closure

74. Form Perception Grouping - Proximity

75. Form Perception Grouping - Similarity

76. Form Perception Grouping - Continuity

77. Form Perception Grouping - Connectedness

78. Form Perception Grouping - Closure

79. Form Perception Grouping
Proximity
Similarity
Continuity
Connectedness
Closure

80. Depth Perception depth perception visual-cliff
the ability to see objects in 3 dimensions, although the images that strike the retina are 2-dimensional
visual-cliff
a laboratory device for testing depth perception in infants and young animals

82. Depth Perception Binocular Cues
such as retinal disparity, that depends on the use of two eyes
retinal disparity
a binocular cue for perceiving depth. By comparing images from the retinas in the two eyes, the brain computes the distance – the greater the disparity (difference) between the 2 images, the closer the object

83. Depth Perception Mononocular Cues
monocular cues
depth cues, such as interposition and linear perspective, available to either eye alone
horizontal-vertical illusion

84. Depth Perception Mononocular Cues
Monocular cues
relative height
relative size
interposition
linear perspective
relative motion
light and shadow

85. Depth Perception Mononocular Cues – Relative Height

86. Depth Perception Mononocular Cues – Relative Size

87. Depth Perception Mononocular Cues - Interposition

88. Depth Perception Mononocular Cues – Linear Perspective

89. Depth Perception Mononocular Cues – Relative Motion

90. Depth Perception Mononocular Cues – Light and Shadow

92. Motion Perception
stroboscopic movement
Phi phenomenon

93. Perceptual Constancy Perceptual Constancy
perceiving objects as unchanging (shape, size, lightness, color) even as illumination and retinal images change

94. Perceptual Constancy Shape and Size Constancies

95. Ames Room

96. Ames Room

97. Perceptual Constancy Lightness Constancy
brightness constancy
relative luminance

98. Perceptual Constancy Color Constancy
surrounding context
surrounding objects

99. Perceptual Interpretation

100. Sensory Deprivation and Restored Vision
Experiments on sensory deprivation
Critical period

101. Perceptual Adaptation
Displacement goggles

102. Perceptual Set
Perceptual set
Mental predisposition
Schemas

103. Perceptual Set Context Effects

104. Perceptual Set Emotion and Motivation
Motivation on perception
Emotions on perception

105. Perception is a Biopsychosocial Phenomenon

106. Is There Extrasensory Perception?

107. Claims of ESP Parapsychology Extrasensory Perception
Telepathy
Clairvoyance
Precognition
Psychokinesis (PK)

108. Parapsychology

109. Premonitions or Pretensions?
Psychic predictions
Nostradamus

110. Putting ESP to Experimental Test
ESP Experiments

111. The End