Sensation and Perception
Fall 2011
Understanding Sensation
Synesthesia
• http://www.youtube.com/watch?v=cRXk8jT5
OPI&feature=related
• http://www.youtube.com/watch?v=0rSbtg7w
ohs&feature=related
• http://www.youtube.com/watch?v=EpCEI0sQ
uWw&feature=related
Processing: Detection and Conversion
• Transduction- process by which a physical
stimulus is converted into neural impulses
Processing: Detection and Conversion
• Coding- process that converts a particular
sensory input into a specific sensation
• Sensory reduction- filtering and analyzing
incoming sensations before sending a neural
message to the cortex
Adaptation: Weakening the Response
• Sensory adaptation- repeated or constant
stimulation decreases the number of sensory
messages sent to the brain, which causes
decreased sensation:
– Example: baby diapers
Adaptation: Weakening the Response
• Gate Control Theory- theory that pain
sensations are processed and altered by
mechanisms within the spinal cord.
– Experience of pain depends partly on whether
the neural message gets passed the “gatekeeper”
in the spinal cord.
• http://www.youtube.com/watch?v=f6idNSaG
2pE
How We See and Hear
• Wavelength- the distance between successive
peaks
• Wave amplitude- the height from peak to
trough
• Range of wave-lengths- the mixture of waves
Hearing
• http://www.youtube.com/watch?v=stiPMLtjY
Aw
http://blogs.psychcentral.com/channel
n/2011/01/tasting/
The Body Senses:
More Than Just Touch
• Skin senses
• Vestibular sense
• Kinesthesia
Sensation and Perception
• http://video.nationalgeographic.com/video/pl
ayer/national-geographic-channel/specials1/brain-games/ngc-brain-games-payattention.html
Understanding Perception
Optical Illusions
• http://www.youtube.com/watch?v=TITFtgH_T
cA
• http://www.youtube.com/watch?v=mf5otGN
bkuc
• http://www.youtube.com/watch?v=6aJlX0AE
Wys&feature=BFa&list=PL28FC7F0D6025E36D
&lf=results_main
Selection:
Extracting Important Messages
• Selective attention
– http://www.youtube.com/watch?v=vJG698U2Mv
o
• Feature detectors
– http://www.youtube.com/watch?v=vwCrxomPbtY
&feature=related
– http://www.youtube.com/watch?v=bAUfCxxytwg
• Habituation
– http://www.youtube.com/watch?v=Kfu0FAAu-10
Organization:
Form, Constancy, Depth, and Color
• Gestalt- a German word meaning “form” or
“whole”
• Gestalts emphasize the importance of
organization and patterning in enabling us to
perceive te whole stimuluse rather than
perceiving its discrete parts as seprarate
entities.
Gestalt Principles
• http://www.youtube.com/watch?v=nxKcpfFvu
f8
Depth Perception
• Learned primarily through experience
• Visual cliff:
Visual Cliff
• http://www.youtube.com/watch?v=4OelrPzp
Q6Q
Binocular vs. Monocular Cues
Color Perception
• Trichromatic theory- theory that color perception
results from mixing three distinct color systemsred, green, and blue.
– First proposed by Thomas Young early 19th century
– Refined by Herman von Helmholtz
• Opponent-process theory- theory that color
perception is based on three systems of color
receptors, each of which responds in an on-off
fashion to opposite-color stimuli: blue-yellow,
red-green, and black-white.
Color Aftereffects
• http://www.youtube.com/watch?v=Gznqc4tsP
HU&feature=fvwrel
Color-Deficient Vision
• Most people perceive red, green, and blue
and are, therefore, trichromats.
• Those who perceive only two colors are called
dichromats.
• People who are sensitive to only the blackwhite syem are called monochromats.
Color-Deficient Vision
• http://www.youtube.com/watch?v=9f0RerFUco
Interpretation:
Explaining Our Perceptions
Sorting through
incoming
sensory
information
Organizing
sensory
information
Interpretation
Interpretation
•
•
•
•
•
Perceptual adaptation
Perceptual set
Frame of reference
Bottom-up processing
Top-down processing
Bottom-up, Top-down Processing
Tou tutally
unferstanb whak I
em trjinq to sey
Bottom-up, Top-down Processing
• http://www.youtube.com/watch?v=0jkaSIOqU
gY
Sensation and Perception
• http://www.youtube.com/watch?v=VwfqUtDP
wyM&feature=results_main&playnext=1&list=
PLCE09901C1FA32E4D