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Myers PSYCHOLOGY
Hearing
(Do you hear what I hear?)
Hearing
Audition - the sense of hearing
Measured in decibels
Absolute threshold - zero
The Intensity of Some Common Sounds
Audition
Amplitude (strength)determines loudness
Frequencythe number of wavelengths determines Pitch - a tone’s highness or lowness
Ear is divided into 3 parts
OuterMiddleInner
See diagram
Audition- The Ear1. Outer Ear - visible part & canal
2. Middle Ear - chamber between eardrum and cochlea HAS three tiny bones
HAS (like a piston - hammer, anvil, stirrup)
that concentrate the vibrations of the eardrum on the cochlea’s oval window
Audition3. Inner Ear
contains the cochlea, semicircular canals, and vestibular sacs
Cochleacoiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses
Hair cells line the basilar membrane
I am sound, where do I go? Ear canal to Eardrum (vibrations) Piston - HAS
Hammer Anvil Stirrup
Cochlea Movement of Hair cells - basilar membrane Auditory nerve
Neural message to the brain Thalamus Auditory cortex of Temporal lobe
How do we hear?
1. Place Theory (Helmholtz) the theory that links the pitch we hear
with the place where the cochlea’s membrane is stimulated;
best for high-pitched sounds
How do we hear?
2. Frequency Theory the theory that the rate of nerve
impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch;
best for low-pitched sounds
How We Locate Sounds?
Locating sound
We locate sound by detecting differences in the intensity (loudness) and timing (speed) of the sounds received by each ear
Why can’t I hear?1. Conduction Hearing Loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
Ex. Damage to eardrum, broken HAS
Why can’t I hear?2. Sensorineural Hearing Loss
hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerve
also called nerve deafnessCrunched the shag carpet - hair cells perm. damaged
Audition Older people tend to hear low frequencies well
but suffer hearing loss for high frequencies
1time
10times
100times
1000times
32 64 128 256 512 1024 2048 4096 8192 16384
Frequency of tone in waves per second
Low Pitch High
Amplitude required forperception relative to 20-29 year-old group
Cochlea implants - clip on Amazing brain
Sign language