Sensation and
Perception
Unit 4
Sensation
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Sensation vs. Perception
Steps to sensation
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1.
2.
3.
4.
5.
Accessory Structures
Transduction
Sensory Neurons
Thalamus or Amygdala
Cerbral Cortex
Bottom-Up processing OR
Top-Down processing
Bottom-Up processing OR
Top-Down processing
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http://www.youtube.com/watch?v=0jkaSI
OqUgY
Sensation
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Psychophysics
Absolute threshold
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Signal Detection theory
Difference threshold
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http://www.garyfisk.com/anim/threshold.swf
Just noticeable difference
Weber’s Law
Sensory Adaptation
Sensation
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Subliminal Stimulation
Primary Sense Areas
Taste/Gustation
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Chemical Sense
Receptors
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Primary tastes
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Taste buds
sweet, salty, sour, bitter, umami
Flavor
Smell/Olfaction
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Emotion
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Chemical
Receptors
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Amygdala
Olfactory rods
Cilia
Primary Odors
Anosmia
Gender
Age
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Light Waves
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Frequency
Amplitude
Vision
Parts of the Eye
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Cornea
Pupil
Iris
Lens
Retina
Eye, cont.
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Receptors
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Fovea
Blind Spot
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Cones
Rods
Optic Nerve
Afterimages
Theories of Vision
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Parallel Processing
Young-Helmholtz
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Trichromatic theory
Opponent-Process Theory
Optical Defects
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Nearsightedness
Farsightedness
Night-blindness
Colorblindness
Hearing
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Sound Waves
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Frequency
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Pitch
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Hertz
Amplitude
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Loudness
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Decibels
Parts of the Ear
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Outer Ear
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Middle Ear
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Auditory Canal
Eardrum
Hammer
Anvil
Stirrup
Inner Ear
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Cochlea
Basilar Membrane
Cilia
Auditory Nerve
http://www.youtube.com/watch?v=7O-adw-HyrQ
Theories of Hearing
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Place Theory
Frequency- Matching
theory
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aka Volley Principle
Hearing Disabilities
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Conduction Deafness
Nerve Deafness
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Aka sensorineural hearing loss
Cochlear implant
Vestibular Sense
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Equilibrium
Inner ear
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Semicircular canals
Vestibular sacs
Touch
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Skin
Pressure
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Depressed
Changes
Active or Passive
Temperature
Pain
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A-delta fibers
C fibers
Serotonin
Endorphins
Gate control
theory
Kinesthetic
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Position and Movement
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Receptors
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Joints and muscles
Perception
Optical Illusions
Perception
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The interpretation of sensory information
Illusions
Gestalt
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When given a cluster
of sensations people
tend to organize
them into a gestalt
A meaningful whole
Necker cube
Gestalt
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Principles by which we organize our
sensations into perceptions
Our brain does more than register
information about the world
Gestalt :Figure-Ground
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The organization of
the visual field into
object (figures) that
stand out from their
surroundings
Figure Ground
More Figure-Ground
More Figure Ground
Gestalt :Grouping - Proximity
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We group nearby figures
************
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Gestalt :Grouping - Similarity
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We group similar
figures together
Gestalt :Grouping - Continuity
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We perceive smooth, continuous
patterns
Gestalt :Grouping - Connectedness
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Because they are linked we perceive them
as a set, even if they are not uniform
Gestalt :Grouping - Closure
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We fill in gaps to create
complete, whole objects
Grouping
Gestalt
Depth Perception
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The ability to
see objects in
3-D although
the images that
strike the
retina are 2-D
Allows us to
judge distance
Depth Perception
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Visual Cliff
Depth Perception
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Binocular Cues
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Depth cues that
depend on two eyes
Retinal Disparity
Binocular Cues
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Convergence
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when projecting images
on the retinas, the eyes
must rotate inward
The closer the perceived
object is, the more they
must rotate
Only effective for short
distances (less than 25
feet)
Depth Perception
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Monocular
Cues
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Depth cues
that can be
gained from
either eye
Monocular Cues: relative height
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We perceive objects higher in our field of
vision as farther way
Monocular Cues: relative size
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If we assume two objects are similar in
size, we assume the smaller one is farther
away
Relative Size
Monocular Cues: interposition
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If one object partially block the view of
another object, we perceive it as closer
Monocular Cues: linear perspective
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Parallel line (railroad tracks) appear to converge in the
distance. The more they converge, the greater their
distance.
Illusions: Muller-Lyer
Monocular Cues: relative motion
As
we move,
objects that are
actually stable
may appear to
move
Monocular Cues: texture gradient
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Most surfaces, such
as walls and roads
and a field of
flowers in bloom,
have a texture. As
the surface gets
farther away from
us this texture gets
finer/smaller/
smoother
Constancy: Size
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We perceive objects as having a constant size,
even while our distance from them varies
Constancy: Shape
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We perceive the form of familiar objects as
staying the same, even though the image on the
retain changes
Contrast: Brightness
Contrast: Brightness
Perceptual Set
Our
interpretation can change depending on
our prior experience
Reversible Figures
More Perception Fun
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I cdnuolt blveiee taht I cluod aulaclty
uesdnatnrd waht I was rdanieg. The
phaonmneal pweor of the hmuan mnid,
aoccdrnig to a rscheearch at Cmabrigde
Uinervtisy, it deosn't mttaer in waht oredr the
ltteers in a wrod are, t he olny iprmoatnt tihng is
taht the frist and lsat ltteer be in the rgh it
pclae. The rset can be a taotl mses and you can
sitll raed it wouthit a porbelm. Tihs is bcuseae
the huamn mnid deos not raed ervey lteter by
istlef, but the wrod as a wlohe. Amzanig huh?
yaeh and I awlyas tghuhot slpeling was
ipmorantt!

Poeetctrd whiitn the park is a daaitmrc
ldsncpaae of sueulrctpd cnnyaos and
srnoaig cfifls, mtsloy from the 170 molliin
year old tan to onagre-red ssoanntde of
the Njaavo Fmtroiaon.
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Protected within the park is a dramatic
landscape of sculptured canyons and
soaring cliffs, mostly from the 170 million
year old tan to orange-red sandstone of
the Navajo Formation.
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The trick behind the hoax is that not only are
the first and last letters in the same place, but
moreover, every consonant appears in the order
of the word.
Only the vowels are removed, rearranged, and
replaced.
This study wasn't done at Cambridge.
7H15 M3554G3
53RV35 7O PR0V3
H0W 0UR M1ND5 C4N
D0 4M4Z1NG 7H1NG5!
1MPR3551V3 7H1NG5!
1N 7H3 B3G1NN1NG
17 WA5 H4RD BU7
N0W, 0N 7H15 LIN3
Y0UR M1ND 1S
R34D1NG 17
4U70M471C4LLY
W17H 0U7 3V3N
7H1NK1NG 4B0U7 17,
B3 PROUD! 0NLY
C3R741N P30PL3 C4N
R3AD 7H15.
Count the Fs
 Finished
files are the result
of years of scientific study
combined with the
experience of years...
How many did you find?
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6
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Most people only count 3
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We usually miss the Fs in of
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One theory is that we “see” it as a V