DO NOW
1. Take a diagram from the front of the room.
2. Fill in the blanks.
Preview p.26
1. Explain the difference between top-down
and bottom-up processing.
2. Provide two examples of top-down
processing in the real world.
3. If you had to give up a sense, which one
would it be? (sight, hearing, touch, taste,
smell)
Aoccdrnig to rscheearch at Cmabrigde
Uinervtisy, it deosn't mttaer in waht oredr the
ltteers in a wrod are, the olny iprmoatnt tihng
is taht the frist and lsat ltteer be at the rghit
pclae. The rset can be a toatl 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.
Sensation
pp.209 -222
NB p.27
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Objective 7: What are the different levels of
processing that occur as visual information
travels to brain?
6 million cones and 120 million rods relay
information via bipolar and ganglion cells
Impulses travel along optic nerve  thalamus
 visual cortex of brain
Feature detectors respond to specific features
of visual stimulus
Supercells provide instant analysis
(movement, angles, postures, etc)
Objective 8: What is parallel
processing?
• Parallel processing: how the brain processes
multiple sources of information
simultaneously
– Color, depth, movement, and form
• Victims of brain damage give us incredible
insight into the workings of the brain’s visual
cortex. Dr. Ramachandran <3
• http://www.youtube.com/watch?v=RuNDkcbq
8PY
Objective 9: How do Young-Hemholtz and
opponent-process theories help us understand
color vision?
• Young-Hemholtz trichromatic theory: there
are three types of cones, each sensitive to a
specific wavelength: red (long), green
(medium), and blue (short)
Objective 9: How do Young-Hemholtz and
opponent-process theories help us understand
color vision?
• Opponent-process theory: color sensitive
components of the eye are grouped in three
pairs: red-green, blue-yellow, and black-white
Objective 10: What is the importance
of color constancy?
• Color constancy: perceiving familiar objects as
having consistent color, even if changing
illumination alters wavelengths reflected by
the object.
• Our experience of color comes not just from
the object, but from everything around it as
well.
Objective 11: How do we experience
pressure waves as sound?
• Our ears transform the vibrating air into nerve
impulses, which our brain decodes as sounds.
– Loudness (decibels)= amplitude
– Pitch (Hertz) = frequency or wavelength
– Prolonged exposure above 85 decibels produces
hearing loss
Objective 12: What are the three regions of the
ear? What series of events triggers electrical
impulses sent to the brain?
Objective 13: What is the difference between
place and frequency theory? How do these
theories help us understand pitch perception?
• Place theory: pitch depends on where
vibrations stimulate the basilar membrane
– High frequency triggers hairs cells on far end
– Low frequency triggers hair cells on close end
• Frequency-matching theory: vibrations of
basilar membrane are determined by the
frequency of vibrations
– high frequency  large vibrations
– Low frequency  small vibrations
Objective 14: How do we pinpoint
sounds?
• The placement of our ears allows us to enjoy
stereophonic (3-D) hearing
Objective 15: What are the two types
of hearing loss?
Conduction hearing loss
– Occurs when eardrum is
punctured or damage to
ossicles
Sensorineural hearing loss
– Occurs when hair cells
located in the inner ear
are damaged
– Mostly permanent
– Nerve deafness
Objective 16: How do cochlear
implants function?
• Cochlear implant: helps convert sounds into
electrical signals that could trigger auditory
nerve to carry message to auditory cortex
• Deaf culture
• Helen Keller “found deafness to be a much
greater handicap than blindness… Blindness
cuts people off from things. Deafness cuts
people off from people”
Process p. 26
• If you had been born deaf, do you think you
would want a cochlear implant?
• Does it surprise you that most lifelong Deaf
adults do not desire implants for themselves
or their children?