AP Psychology Unit 3: The Ear, Sound, and Deafness

pathway of sound

sound → pinna → auditory canal → ear drum (tympanic membrane) → hammer, anvil, stirrup (HAS) → oval window → cochlea → auditory nerve → temporal lobes

outer ear

made up of pinna and auditory canal, collects and magnifies sound waves

middle ear

made up of ear drum, HAS

inner ear

made up of cochlea and basilar membrane, helps balance 

pinna

outer ear, helps direct sound into the ear

auditory canal

outer ear, funnels sound into the ear from the pinna and into the eardrum

malleus (hammer)

helps with amplifying sound sent in from the eardrum and into the inner ear

you can HAMMER MALLEable metal

incus (anvil)

helps with amplifying sound sent in from the eardrum and into the inner ear

anvil-shaped 

oval window

located in the opening of the wall of the cochlea, covered with a membrane that helps with amplification of sounds and sends waves into the inner ear

cochlea

inner ear, filled with fluid, where sounds are first processed, has 3 canals, contains hair cells that line the basilar membrane 

basilar membrane

in the cochlea, lined with hair cells 

place theory

asserts that sound waves generate activity of different places along the basilar membrane, location where hair cells bend determines sound

frequency theory

asserts that pitch is sensed because of the rate of neural impulses is equal to the frequency of the sound, rate of action potentials determines sound

deafness

the inability to hear, occurs from damage to ear structure of the neural pathway of the ear

conductive deafness

deafness caused by injury to the outer or middle ear structures, can be helped by hearing aids

sensorineural deafness

deafness caused by impairment of structures from the cochlea to the auditory cortex, mild forms can be helped with hearing aids, profound forms can only be helped with cochlear implants

cochlear implant

device that converts sound into electrical signals, can help profound sensorineural deafness

hearing aid

a device that amplifies sound to allow an individual to hear different sounds around them, can help conductive deafness and mild sensorineural deafness