Sensory perception 2012_


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  • No, but the shape of the ear does.
  • You would not enjoy massage. You would not be able to play a musical instruments that require a sense of pressure . No enjoyment from touch activities: kissing? You would not know if there was wind blowing on your face. You would not feel a sense of speed from the car moving. Jobs that involve touch might be difficult: Massage therapistChiropractorDoctor/SurgeonDentist?ChefYou would not know if you burned yourself, or if you were cold or hot. If you could not sense pain you through your skin you might do really well at martial arts or boxing. Sense of touch evolved because we really need these in our everyday life for survival and for pleasure.
  • Hold finger in front of you. Close one eye then the other, finger shifts. Use the angle of the eyeball to gauge distance.
  • Gestalt principle of proximity
  • Face on mars
  • Sensory perception 2012_

    1. 1. What do you see? Visual Illusions• Mermaid but not a mermaid• qUo&list=UU0W6lFhlMFdbK8dGTTTfEqw&ind ex=23&feature=plcp• ko#p/u/12/KJFozypEMd4
    2. 2. Saccade?•
    3. 3. Sensation• Process of receiving information from the environment.• What kind of Info?
    4. 4. If you had to lose one of your senseswhich one would you choose to lose? Why?
    5. 5. Process ofPerception organizing sensory information to make it meaningful.
    6. 6. Absolute Threshold• The Level of sensory stimulation you need in order to sense something 50% of the time
    7. 7. Vision Absolute Threshold Vision Absolute ThresholdCandle flame seen from _______ kilometersaway at night
    8. 8. Hearing Absolute ThresholdWatch ticking under quiet conditions from___ meters away
    9. 9. Touch Absolute Threshold• A bee’s wing falling on your cheek from ____ centimeters above
    10. 10. Smell Absolute Threshold• In how many rooms can 1 drop of perfume be sensed?
    11. 11. Taste: Absolute Threshold 1 teaspoon of sugar in how many liters of water?• 7.5 liters of water
    12. 12. Sense of Taste• Taste Receptors – Five kinds of Taste Receptors • Sweet • Sour • Salt • Bitter • New one? Umami
    13. 13. Umami Examples• Japanese: dashi with kombu seaweed and dried bonito flakes• Chinese: add Chinese leek and cabbage with chicken soup, as in the similar Scottish dish of cock-a-leekie soup• Italians: combine Parmesan cheese on tomato sauce with mushrooms.
    14. 14. Taste Buds on Tongue
    15. 15. Taste Receptors• Taste Buds
    16. 16. How do your taste needs develop?• Baby salt needs? Teen salt needs? Adult salt needs?• Baby sugar needs? Teen sugar needs? Adult sugar needs?
    17. 17. Salt Needs Newborn does not need saltFew months old baby to adulthood want salt Later adulthoodNeeds for salt tapers off Older people Need for salt returns!
    18. 18. Sugar Needs • Built-in • Body needs sugar for energy • Too little sugar makes you tremble
    19. 19. Bitterness detectors: why do we need them?• Play an important role detecting poison.• Food gone bad has a sour taste
    20. 20. Taste Experiment• 1. Blindfold yourself.• 2. Open your mouth wide, say “Ah”• 3. Wait for the food to touch your tongue (Partner you will place item on tongue)• 5. Taste the food.• 6. Identify the food• 7. Taste in total five different items.• 8. Switch with your partner
    21. 21. Critical Thinking• You have to deliver a brief speech to your class on salt and sugar needs. What do you say?
    22. 22. ARE YOU A SUPERTASTER? Use blue food coloring and a plas reinforcement ring for a three-hol binder (paper reinforcement rings get mushy). Use a cotton swab to wipe some blue food coloring on tip of your tongue. Place the ring on your tongue. If are a medium taster, youll see on few little “mushrooms" inside the rings opening. If youre a superta youll find more than 25 of them w the circle. How many do you cou
    23. 23. Are you a supertaster questionnaire?• ody/interactives/supertaster/
    24. 24. TasteDISCUSSION QUESTIONS1.What might be some evolutionary advantagesto being a supertaster -- for animals andhumans?2.What other factors might explain a personsfood preferences?
    25. 25. Pair Talk• 1. What is the difference between sensation and perception?• 2. What is the weakest light that can be seen? The lightest touch that can be felt? What are these minimum detection levels called?
    26. 26. Hearing• Sound waves: – Faster or slower than light waves?• Many animals use sound more than humans. – For example? • Dolphin clicks • Bats
    27. 27. Sound Characteristics• Pitch – How high or low the sound is• Timbre – Complexity of the tone • Eg. Differences between guitar, piano, trombone
    28. 28. Sound Characteristics• Intensity – Measured in decibels – Above 130: painful – 70 decibels: can disturb sleep: fridge – 50 decibels: can help sleep if sound is continuous
    29. 29. My what big ears you have!• Does ear size make a difference?
    30. 30. • Piece of skin stretched tightly over the entrance to the rest of the eareardrum • Vibration causes bones to vibrate too. • 3rd bone cochlea is filled with fluid and hair cells Bones • Give off electrical particlesHair cells • Electrical particle goes to the brain where sound is interpreted.Auditory Nerve
    31. 31. Why?• Eyes in front?• Ears on the side?
    32. 32. How does sound affect you? How to listen?• Bird Song oDU&feature=related• Video• ows_how_to_listen.html
    33. 33. Hearing Websites• Hearing Loss: what it sounds like ringloss/hlsoundslike.htm• Pets and hearing:• High Frequency tones
    34. 34. ption.html• Michael Shermer says the human tendency to believe strange things -- from alien abductions to dowsing rods -- boils down to two of the brains most basic, hard-wired survival skills. He explains what they are, and how they get us into trouble.
    35. 35. What’s This?• In pairs, walk hurriedly around the room• The first student points to objects asking "Whats this?"• The second student must quickly answer with anything that the object is not. – If its a doorknob, reply that its The Hubble Telescope or a vampire. – This is surprisingly difficult for our pattern-based brains – Its the questioners job to make sure that the answerer is not making it easier by simply going through a list – If they are, a friendly and high-pitched "No!" from the questioner can signal that the answer is not good enough. – This continues until brain-freeze occurs in the answering student, which it will, then they switch roles and continue.
    36. 36. What’s This? Advanced Version• A more advanced version can be done by NOT allowing for any association at all between succeeding answers• EXAMPLE: – "Whats this?" "A telescope" "Whats this?" "A magnifying glass" • This answer receives a little "No!" from the questioner
    37. 37. Smell: Olfaction• (Not good, Good, Very Good) in humans• Odor and emotional event – Very hard to forget (Engen, 1987)
    38. 38. Odor Moleculesattach to hair in the noseElectrical signal sent toOlfactory bulb Sends code to brain for interpretation
    39. 39. • Animals release this odor chemical to communicate sexual interest
    40. 40. Smell and Taste• Smell is (less, more) important than taste in eating.• What happens when you hold your nose and eat?Experiment Get a yogurt container Blindfold yourself Plug your nose Taste the food and identify all of them. Use the toothpick or clean fingers
    41. 41. Pheremones in Humans• ??• LuQ
    42. 42. Touch=Cutaneous Senses 3 types of receptors – Pressure – Changes in Temperature – Pain – Burn: Active Continuously: records injury or po
    43. 43. Psychology and you, page 103• In Focus problem• Your fingers are cold after handling ice or snow.• You run your fingers under warm water, but the water seems hot.• Can you think of a theory about cutaneous receptors to explain this?
    44. 44. Task• Your task is to develop a list of consequences for the loss of cutaneous senses.• 1. What are the consequences for the loss of the ability to process touch information? (pressure, texture, vibration)• 2. What are the consequences for the loss of the ability to sense temperature? Loss of the ability to sense pain?• 3. What do these consequences suggest about how evolutionary pressures may have influenced the development of cutaneous sense?
    45. 45. Perception• Put together sensory information so you can understand the input coming in.• Involves Interpretation and Expectation.
    46. 46. Perceptual Constancies• Brain need to keep things the same in order to maintain order and make sense of the environment.• Causes use to experience illusions
    47. 47. Size Constancy• Definition: The ability to remember how large an object is no matter where it is.• Our perceptions of the size of objects are relatively constant despite the fact that the size of objects on the retina vary greatly with distance.
    48. 48. Colour Constancy• Colours are perceived as the same• Move apple to a darkened room, does it change colour?• Only works with things we know the colour of already.
    49. 49. • Are these fruit the same colour?• Why do we perceive them the same colour?
    50. 50. Brightness Constancy • The tendency for a visual object to be perceived as having the same brightness under widely different conditions of illumination.
    51. 51. Example of Brighness Constancy: White Paper• A sheet of white paper seen in the bright sunlight reflects a very different amount of light than the same sheet of paper seen later that night in a softly lighted room.• Yet we perceive the paper as having the same whiteness in each case.
    52. 52. Shape Constancy• Shapes of things stay the same.
    53. 53. Shape Constancy• Everybody has seen a plate shaped in the form of a circle. When we see that same plate from an angle, however, it looks more like an ellipse.
    54. 54. Space Constancy • The visual world appears to us as stable and unmoving despite continuing movement of the retinal image
    55. 55. Space Constancy How?
    56. 56. Space Constancy• Things appear steady to us because we either focus on the outside as moving OR
    57. 57. • When driving, we use self-motion – Cars moving in front of us are held steady in our minds – Only a major change in motion is perceived. – Small changes in speed are not easily perceived • Thus rear enders.
    58. 58. Depth Perception• Ability to see objects 3D and to judge distance.• Visual Cliff Experiment with babies• Showed babies have depth perception from beginning.
    59. 59. Visual Cliff Experiment• Q6Q
    60. 60. Case Study #1: page 111, Text• Virgil
    61. 61. Seeing is Believing Case Study handout
    62. 62. How do you see Depth?
    63. 63. Retinal Disparity • See different things with each eye • Use the angle of the eyeball to gauge distance
    64. 64. Texture Gradient• We use texture to give us clues as to how far away the object is.• Texture: – How smooth or rough something is• Gradient: – Different levels of texture we see at different distances
    65. 65. Task• 1. List occupations in which good vision, hearing, or other senses would be important for success. Be sure to list the reasons why. Are there occupations in which poor ability in one of the senses would be dangerous?
    66. 66. Perceptual Organization• Gestalt Psychology – Make things into wholes – Use Perceptual cues to make sense of things
    67. 67. Gestalt Principles of Perceptual Organization• Principle of Common Region
    68. 68. Gestalt Principles Principle of similarity • Here, organization depends on the shape.
    69. 69. Gestalt Principles Principle of similarity
    70. 70. Principle of Similarity
    71. 71. Gestalt Principles
    72. 72. Gestalt PrinciplesPrinciple of Proximity – objects or shapes that are close to one another appear to form groups
    73. 73. Gestalt Principles• Principle of Closure or Good Continuation – Elements group to form smooth lines
    74. 74. Figure Ground: Has to be one figure and one ground• Reversible Figure
    75. 75. More examples Gestalt principles• s/process/gestaltprinciples/gestaltprinc.htm#s imilarity
    76. 76. Illusions We perceive something inaccurately=> misperception mazing-3d-sidewalk-art-photos/
    77. 77. Colour Constancy Illusions• _illusions_show_how_we_see.html
    78. 78. Reversible Figure• Necker Cube: 2 ways to view this cube
    79. 79. Reversible Figure
    80. 80. Illusion: paper shelf• How is it done?
    81. 81. Questions• Critical Thinking: – Draw an original example for each of the following principles of perceptual organization: similarity, closure, proximity, and figure ground. 2 points per = 8 points
    82. 82. Discuss in pairs: Page 120 #2, #3, #5, #7Then, we will discuss together
    83. 83. Sensation: Vision• How is colour seen?
    84. 84. What is the sun or light bulb colour?• White
    85. 85. When do you see colour?• Waves of white light hit objects and bounce back to us at different speeds or frequencies.• All the colours are absorbed in the banana except for yellow which is reflected back.
    86. 86. No such thing as colour• Different light wavelengths have different names• Eyes have different receptors for different wavelengths
    87. 87. Examples of different wavelengths
    88. 88. Which wavelengths do we not see?• Infrared: Radio, tv, microwaves• Ultraviolet: x-rays, gamma rays, cosmic rays
    89. 89. What do bees see?
    90. 90.
    91. 91. What do Snakes see?Snakes have two sets of eyes.One set is the normal eyes that you see,and they detect color quite well.But they also have vision pits that detect heatand “see” living creatures like an infrared detector.Snake eye vision simulator program:
    92. 92. Light Waves and Shotgun pellets
    93. 93. LensHelps to focusobjects to the back ofthe eye. If lens is notshaped correctly theimages fall in thewrong spot.
    94. 94. • Glasses change the angle at which the image falls
    95. 95. Retina• Lights hits the retina• Optic nerve area: no receptors thus blind spot• Experiment – Draw this on a piece of paper – Close your right eye, look at the plus sign and then move your face forward till dot disappears. – Close your left eye, look at the dot till the plus disappears.
    96. 96. Blind Spot
    97. 97. Blind Spot Experiments
    98. 98. More Blind Spot Experiments Textbook page 94
    99. 99. Colour: Rods and Cones• Rods: violet – purple range  see black and white with them.• Sensitive in low light conditions• They keep blue objects visible in the darkness• Packed into the sides of the retina
    100. 100. Cones• Used for daylight conditions• Respond best to red wavelengths• Don’t work with low light• Located in the center of the retina
    101. 101. Colour Defects • Colour blindness – The inability to tell the difference between certain colours
    102. 102. • Most common form of colour blindness is which colour?
    103. 103. Colour Blind TestTextbook: page 96
    104. 104. AfterimagesOccurs during the course of visual perception when the optical stimulussuddenly disappears.Example:Put a piece of hot coal on a string.When not moving it is a dot, but when moving it becomes a line.1765,Chevalier Patrice d’Arcy (1725–79): afterimage lasts as long as the time taken forthe piece of coal to make one revolution, i.e., a minimum of 0.133 or 8/60th of asecond. Consequently, in the case of film footage, 16 sequential images per secondare perceived as continuous movement. from:
    105. 105. Afterimage: why does it occur?Chemicals in the eye get used up when lookingat images. Ie. Eyes get “bleached”When you look away, the chemicals are still inyour eye and you see the image (but in differentcolours).Cones system tries to restore balance afterlooking at something. Don’t normally see thembecause images are replaced all the time.
    106. 106. Afterimages Occurs because the eyes want to stay in balance. Try these: http://faculty.wa dler/after.html
    107. 107. Super Taster Questionnaire, Visual Illusions• Experience some on-line• Can you explain these illusions? Why are your eyes being fooled?
    108. 108. Review• From questions on page 97 of text. Do by yourself.• 1. What’s the difference between sensation and perception?• 2. Why do some objects appear blue to us, while others appear red?• 3. Why is there a blind spot?• 4. Name what each part of the eye does: rods, cones, iris, lens• 5. What colours does a colour blind person usually not see?
    109. 109. Subliminal Perception• What is it?Subliminal perception occurswhenever stimuli presented belowthe threshold of awareness arefound to influence thoughts,feelings, or actions.• Does it work? Read page 98-99. Discuss in small groups
    110. 110. Unconscious language learning• Do they pick up on the concealed pattern when tested? “The answer is yes,” said Dr. Williams, whose research was funded by the Economic and Social Research Council. “We found significantly above-chance selection of sentence constructions that were ‘grammatically correct’ according to the hidden pattern. Yet, the participants had no awareness of what they had learned or how. Moreover, we were able to show learning of the same material by native speakers of two typologically very different languages, English and Cantonese.”• Interestingly, picking up the hidden pattern unconsciously doesn’t always happen – if, for instance, the hidden pattern is linguistically unnatural, such as a correlation with whether an
    111. 111. Make up 2 True or False Questions for the quiz tomorrow.
    112. 112. Subliminal Language Learning?• The research provides a window onto unconscious learning processes in the mind and highlights an important element that has practical implications for language teaching. In each test, the learner’s attention was directed to the part of the sentence that contained the hidden pattern. By directing attention, it seems that other elements of the sentence construction are picked up unconsciously.• “In a teaching situation, merely teaching the rules of a language may not be the only answer,” explained Dr. Williams. “Instead, using tasks that focus attention on the relevant grammatical forms in language could help learners access unconscious learning pathways in the brain. This would greatly enhance the speed of acquisition of a second language.”• Provided by University of Cambridge
    113. 113. Subliminal Advertising• Lw