Schiffman Ch. 2

1
(No Transcript)
2
Eye Disorders

• Corneashape (nearsighted, farsighted,
  astigmatism), transparency loss
• Lenscataracts
• Pressureglaucoma
• Retinaretinal detachment, macular degeneration,
  diabetic problems, albinism
• Optic nervemyelin loss
• CNSbrain injuries

3
Eye Disorders

• Muscle controlnystagmus, strabismus, amblyopia

4
(No Transcript)
5
Afterimages

• Negative afterimagesdue to rebound effects
  after adaptation
• Color Aftereffect

6
(No Transcript)
7
(No Transcript)
8
Theories of color perception

• Trichromatic (Young-Helmholtz)
• Evidenceshine white light on cones get 3
  absorption curves

9
(No Transcript)
10
Theories of color perception

• Opponent process (Hering)cells respond in
  opposite ways for red-green, yellow-blue,
  black-white
• Negative afterimages
• Combination 3 types of cones linked to neural
  opponent process cells (in retina, thalamus,
  visual cortex)

11
Defective color vision

• Usually due to deficiency of cone pigment
• If lack red pigment (one that would respond to
  red) it affects green also, as that input to
  cells missing

12
(No Transcript)
13
Figure-Ground

• Figurestands out, smaller, seen as solid object
• Groundrecedes, larger than object, encloses
  figure
• Ambiguous figure-ground, as in Escher artworks

14
(No Transcript)
15
(No Transcript)
16
(No Transcript)
17
(No Transcript)
18
Impossible trident explanation

• Figure is impossible in 3-D, and cant be
  visually resolved in 2-D (drawing) because of
  shifting of elements from figure to ground
• See Impossible Trident for longer explanation

19
Gestalt laws of perception
20
proximity

• See rows or columns?

21
Common fate
22
Similarity proximity

• Visual Demonstrations
• Above link may enable demos of other Gestalt laws
  also

23
Subjective Contours
24
(No Transcript)
25
(No Transcript)
26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
Optic flow

• optic flow
• Im moving forward, or something is moving toward
  me
• Symmetrical expansionIm going straight ahead or
  somethings coming straight at me
• Asymmetrical expansionIm not going straight
  ahead or it will miss me

30
Biological motion

• BMLwalker
• Can tell male vs. female based on motion of
  point-light displays, biological vs. random, can
  recognize animals
• Biological Motion
• BioMotionLab Projects

31
Apparent movement

• Illusory movement of stationary stimuli
• Stroboscopic movementas in movies need to
  exceed critical flicker frequency for smooth
  movement
• Phi phenomenon Phi Phenomenon (Apparent
  Movement)
• Optical Illusions and Visual Phenomena including
  wagon wheel

32
Motion aftereffects

• Waterfall illusion
• Waterfall Illusion (bars, not water)
• Motion After-Effect

33
Monocular cues

• Interpositionpartial occlusion

34
Monocular cues

• Interposition

35
Monocular cues

• Aerial perspective elevation

36
Monocular cues

• Shading and lighting

37
Shadow and motion

• Shadow Ball

38
Monocular cues

• Shading and shape

39
Monocular cues

• Shading and light direction assumption

40
Monocular cues

• Linear perspective

41
Monocular cues

• Linear perspective

42
Monocular cues

• Texture gradient

43
Monocular cues

• Relative size

44
Monocular cues

• Motion parallaxfixate on a point, move head
  items closer than fixation point move faster than
  ones farther away, and in opposite direction
• Static demo to illustrate different directions
  and rate of motion Psyc/Biol 240 - Motion
  Parallax

45
Ames room illusion

• Size constancy distorted by room that is
  different shape than it looks for more info, see
  Ames Room

46
Illusions of depth, distance, constancy

• Moon illusion
• Moon Illusion Demonstration Applet
• Various theories still hotly debated. If you
  really want to wade into debate, look here The
  Moon Illusion

47
Size/distance illusions

• Muller-Lyer illusion
• Muller-Lyer Illusion
• Perspective theory one looks like receding
  edge other looks like edge coming toward you
  one that looks farther away must be longer
• However blind people feel the illusion
  tactually! Maybe we just average in the
  extended lines

48
Size/distance illusions

• Ponzo illusion
• The Ponzo Illusion
• Could be distance illusion
• However could be that lines that approach
  borders look larger

49
Misc. illusions

• http//www.ritsumei.ac.jp/akitaoka/index-e.html
• Counter-Rotating Spirals Illusion
• Amos Storkey - Visual Illusions
• Optical Illusions Visual Phenomena

50
The ear functional anatomy

• BBCi - Science - Human Body - Nervous System
  Layer
• http//www.hhmi.org/biointeractive/animations/coch
  lea/cochleaWeb.mov

51
Lateralization

• Left hemisphere sequential (bottom up),
  syntactical, phonetic, word meanings, analysis of
  musics meaning
• Right hemisphere holistic, integrative (top
  down), sight words, inferences, knowledge base,
  speed reading, overall sound of music
• Note even chimps have some lateralization

52
Echolocation

• Similar to sonar, ultrasound
• Studies of blind individualsif get rid of
  auditory cues, cant navigate around objects in a
  room also, put microphone on another person, and
  let blind person listen to what microphone picks
  up as person walks aroundalmost as good as if
  blind person were walking
• Stevie Wonder coin counting

53
Music

• Octavesfrequencies are double
• Notes octave apart sound more similar than any
  two in between
• Perfect pitch
• Amusiaprofound lack of musical perception cant
  recognize tones or reproduce them
• Musical agnosiainability to recognize
  music/melodies

54
Perceiving music

• Gestalt principles notes go together that are
  in proximity, similar in pitch, have common fate
  (go up or down together) also closure figure
  ground
• Constancyfor anyone without perfect pitch, can
  sing song without knowing what key you are
  inrelationship of notes is what is constant, not
  absolute pitches

55
Speech

• Do we have linguistic (e.g., phoneme) feature
  detectors? Study listen to repeated sound (d
  d d d d) for 2 min., then hear ambiguous sound
  (halfway between d and t), tend to hears sound
  other than one have been listening to (t) like a
  speech-based negative afterimage

56
Brain speech

• Wernickes area speech reception
• Brocas area expressive speech
• Broca
• Neuroscience for Kids - Language
• Very specific deficits can occur loss of
  ability to know word meaning for certain words,
  but only when used as a verb, not same word as a
  noun loss of naming ability for fruits
  vegetables

57
Vestibular apparatus
58
(No Transcript)
59
Semicircular canals
60
Semicircular canals

• 3 canals represent X, Y, Z axes, so any motion
  can be represented as a combination of motions in
  these 3 directions
• Responds mainly to acceleration
• Motion aftereffect spinning around, stop, world
  spins opposite direction

61
Disorders

• Menieres disease caused by high fluid pressure
  in labyrinth symptoms include dizziness, nausea,
  hearing problems
• Motion sickness mismatch between visual input
  and signals from vestibular apparatus one theory
  about adaptive value of nauseasimulates visual
  input when poisoned

62
(No Transcript)
63
(No Transcript)
64
(No Transcript)
65
Sensory deficits

• Braillehigh sensitivity of fingers helps note
  word superiority effectletters in words
  recognized faster than individual letters (top
  down processing)
• Tadoma method for people who are blind and
  deafhand touches mouth and face to pick up
  vibrations
• Touching audio speaker to feel vibrations

66
Tactile vision

• Tactual-visual substitution systemchair with
  vibrating pins note trade-off between large area
  (back) but also large 2 point touch thresholds
• Fingers tongue might work better

67
(No Transcript)
68
seeing tongue

• Article about seeing tongue is here
• The Seeing Tongue Science News Online, Sept. 1,
  2001
• (may summarize for extra credit)
• With experience, can recognize some objects, some
  depth cues
• Works best if blind person controls camera
  movement cues important

69
Tickling

• Unpredictability necessary cant tickle self
  effectively
• fMRImore activation of somatosensory cortex when
  tickled by device operated by someone else than
  when operated by self

70
Temperature

• Cold receptorsclose to surface hot
  receptorsdeeper
• Why do different objects at same temperature feel
  like different temperatures? (e.g., wood
  metal)
• Thermal conductivityhow fast does the object
  conduct heat away from skin
• Getting burneddepends partly on heat content
  thermal conductivity

71
Thermal adaptation

• Contrast effectsput one hand in cold water
  other in hot water for few minutes when then put
  both hands in medium temperature water, get
  different sensations

72
Pain

• Adaptivenessexample in text about woman without
  pain sense (chronic pain insensitivity)
• Different types of painsharp, highly localized
  dull, diffuse
• Referred pain

73
Pain

• Thresholddepends on many factors psychological
  factors (experience with specific pain,
  expectations (e.g., fear), self distraction,
  genetic differences, presence of other
  stimulation (e.g., acupuncture or acupressure)

74
Gate control theory of pain

• Large fibersfast, acute
• Small fibersslow ache, dull
• Can close gate for small fibers by stimulating
  large fibers (e.g., rubbing, acupuncture,
  acupressure, electrical stimulation, etc.)
• Emotional arousal also seems to shut off
  perception of pain

75
Acupuncture

• Meridians based on Chinese acupuncture not
  logical locations, based on what is now known
  about nervous system modern acupuncture is more
  logical

76
Endorphins

• Naturally occurring morphine-like chemicals in
  brain
• Increase in response to pain

77
Taste

• Transductionchemoreceptors taste cells located
  in taste buds
• Primary tastessweet, sour, salt, bitter,
  (maybe) umami (savory, meaty, MSG)
• NOT distributed in specific parts of tongue, as
  used to be thought

78
(No Transcript)
79
Taste cells

• Each type responds best to best stimulus, but
  all respond some to all stimuli
• labeled linebest stimulus connected by
  specific pathway to specific part of brain, which
  indicates which cells were stimulated

80
Cross-fiber patterning

• Taste is due to pattern of receptor activation
• Taste generalizationchemically similar stimuli
  cause similar pattern of responding

81
(No Transcript)
82
Genetics

• Thresholds for some stimuli (e.g., vanillin, PTC)
  are bimodalsome can taste easily (tasters),
  others not at all (nontasters)genetic basis
• Supertasters25 of tastersperceive some bitter
  substances much more strongly than do regular
  tasters may be due to more taste cells
• More taste cells linked to obesity

83
Adaptation

• Aftereffectsadaptation-produced potentiation
• Exposure to taste, then neutral (e.g., water)
  neutral then has a taste

84
Sugar substitutes

• Two ways to have no or few calories
• Body cant process
• So sweet dont need much
• Some studies show that sugar substitutes do not
  decrease our sugar intake (we find ways to get
  sugar in our diet by eating other things with
  sugar)

85
Specific taste preferences

• Selective deprivation can increase preference for
  that taste (e.g., rats salt)
• Assumption is that if body needs something, we
  will crave it and find it more pleasant tasted
  than usual
• Prenatalwhat mother eats and drinks can affect
  babys food preferences some

86
Taste preferences

• Cultural factorssensitive period for first two
  years foods infant exposed to will be eaten
  readily throughout life otherwise, takes more
  effort to learn to like or tolerate
• Evolutionary logic of learned preferencesfrom
  available foods in environment, need to learn
  from adults which to eat which to avoid

87
Conditioned taste aversion

• Garcia Effectone trial taste aversion to
  something that made you sick
• Only exceptions are among animals that are food
  specialists (e.g., vampire bats), who do not face
  the omnivores dilemma

88
Odor quality

• Hennings smell prism
• http//www.aug.edu/psychology/faculty/SMELLANDTAST
  E.ppt

89
Odor theory

• Stereochemicalshape of molecule but, more
  recent evidence does not support
• There is no accepted theory for how odors are
  classified

90
Olfactory disorders

• Anosmiacant smell
• Hyposmiadecreased smell
• Hyperosmiaincreased smell
• Dysosmiadistortion in smell
• Phantosmiaolfactory hallucinations
• Possible causes drugs, chemotherapy, injury,
  disease, genetics

91
coding

• Adaptation rebound occur
• Cross-adaptation (similar odors) occurs
• Mixturesone odor can mask another

92
Smell preferences

• Evolutionary basisattracted to smells associated
  with things that are good for us, such as ripe
  fruits disgusted by things that are bad for us,
  such as decay, body wastes ( skunky beer?)
• Concentration matters
• Prefer familiar odors, including own odor

93
Odor memory

• Stronger memory for odor than for other senses
• Strong cue for autobiographical memories
• State-dependent memoryodor affects

94
Other psychological effects

• Aromatherapyhelps people relax, but dont expect
  to cure psychological disorders this way
• Pheromonesmany have been identified in animals,
  but research with humans still controversial
• But sweaty T-shirt studyfemales prefer smell
  of symmetrical males

95
Other psychological effects

• Male smell also tends to relax females (remember
  that concentration matters)
• McClintock effectsynchronicity of menstrual
  cycles among women living together appears to be
  odor mediated

96
Common chemical sense

• Chemical irritants on mucosal surfaces stimulate
  a type of pain receptor causes reflexive
  behaviors to get rid of irritant (e.g., sneezing,
  coughing)
• Preferences for irritating chemicals, such as hot
  pepperscant get animals to learn such
  preferences may be adaptive in some locations
  (kills bacteria, aids digestion)