Transcript Module 10

Module 10
Hearing and Other Senses
Chapter 3, Pages 108-120
Essentials of Understanding Psychology- Sixth Edition
PSY110 Psychology
© Richard Goldman
October 9, 2006
Ear
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Converts sound waves into nerve pulses
Senses motion
Helps maintain balance
Ear Structure
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Outer Ear
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Pinna
Auditory canal
Eardrum (Tympanic
membrane)
Middle Ear
Ossicles (bones)
 Hammer
 Anvil
 Stirrup
 Eustachian tube
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Inner Ear
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Oval window
Cochlea
Basilar membrane
Hair cells
Auditory nerve
Semicircular canals (3) – motion
sensors
Otoliths- orientation & acceleration
sensors
Orientation &
Acceleration
Otoliths
Sound
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Compression wave (not transverse) that travels through a
medium
Human can hear sound in the range of 20-20,000 Hz
(cycles per second) – pitch
Amplitude – Intensity of sound – measured in decibels (a
10X logarithmic scale) – sounds greater than 120db is
painful
Sensitivity –
Sound Waves
Sound Localization
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Differences in intensity and time differences
between sound reaching each ear help the
brain determine what direction the sound
came from
Theories of Hearing
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Place Theory – Excitation of specific
locations on the basilar is responsible for
frequency discrimination
Frequency Theory – Excitation across the
basilar membrane in sync with the sound is
responsible for frequency discrimination
Hearing Loss
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Damage due to:
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Physical damage – cotton swab (Q-tip)
Illness – Mumps
Prolonged exposure to loud sound
Brief exposure to very loud sound
My be corrected with:
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Hearing aid – auditory discrimination is often a
problem
Cochlear implant
Deaf Culture
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Some people believe that belonging to a deaf
culture is just a good as belonging to a
hearing culture.
Olfaction - Sense of Smell
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Humans can detect > 10,000 separate smells
1,000 different specialized types of olfactory
cells
Pheromones – secreted odors use to
communicate
Gustation - Sense of Taste
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Taste results from combinations of stimulating
4 different types of taste buds located on
tongue, in mouth, and throat.
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Sweet
Sour
Salty
Bitter
Humans have about 10,000 different taste
buds
Each taste bud is replaced every 10 days
Interrelation of Taste and Smell
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The perception of taste often relies on the
perception of smell to identify a food
substance
Skin Senses:
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Touch
Pressure
Temperature
Pain
Pain
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Gate-control theory - Pain is a perception
under control of the brain
Treatments:
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Medication
Electro stimulation of the nerve
Light Therapy
Hypnosis
Surgery
Cognitive Restructuring - Rewrite of the pain
“script”