Audition Flashcards
What effects the pitch of a sound?
The frequency of the waves
What is the pinna?
The outer ear
What is the role of the pinna?
Directs sound
What is the entrance to the ear?
The ear canal
What do sounds strike?
The ear drum
What do the bones of the ear do?
Amplify and transmit the waves to the fluid of the inner ear
What is the cochlear?
Coiled tube
Three chambers
Fibres have different what?
Resonance frequencies
What happens when the fibres move?
They trigger the hair cells which send an impulse to the cochlear nerve
By what factor does the middle ear amplify sound?
x20
What is the proper name for the ear drum?
Tympanic membrane
What are the three bones of the ear?
Malleus
Incus
Stapes
What is the eustachian tube?
Connects the middle ear to the nose
What is the attenuation reflex?
Loud sound causes muscles of the middle ear to contract reducing conduction to the cochlear
This adaptation is both protective and helps discern high frequency sounds
What are the three chambers of the cochlear?
Scala vestibuli
Scala media
Scala tympani
What is the organ of Corti?
Stereocilia interact with the tectorial membrane
Stereocilia are on the surface of hair cells
Hair cells connect to auditory nerve
What does movement of stereocilia trigger?
Depolarisation of hair cells
How are different frequencies identified?
Very low frequency - phase locking
Intermediate frequency - phase locking and tonotopy
High frequency - tonotopy
How is sound located?
Interaural delay
Interaural intensity differences
What is the pathway of the cochlear nerve?
Cochlea Ventral cochlear nucleus Dorsal cochlear nucleus Superior olive Lateral lemniscus Inferior colliculus Auditory cortex
What could be causes of deafness?
Conduction disrupted
Obstruction of the auditory canal
Middle ear infection
Head trauma
How would the cochlea nerve be damaged?
Effect of antibiotics, kanamycin and gentamicin
Damage to dorsal cochlear nucleus
What happens if hair cells are damaged?
Tinitus
Noisy ear
