Lecture #5 - hearing disorders Flashcards
how many components does the inner ear have ?
3
what are the 3 components of the inner ear ?
- vestibular apparatus
- cochlea
- auditory nerve
what are the 7 main parts of the ear ?
- pinna
- ear canal
- ossicles
- ear drum
- eustrachian tube
- cochlea
- auditory nerve
what is the function of the vestibular apparatus ?
responsible for balance and equilibrium (where our body is in space)
what are the two parts of the vestibular apparatus ?
semicircular canals & vestibule
what does the semicircular canals help sense and maintain ?
balance
what is the vestibule ?
the entry way to the inner ear
how many organs does the vestibule contain ?
two
what are the two organs in the vestibule responsible for ?
linear acceleration and gravity
what part of the ear is the cochlea ?
the inner ear
what is another term for teh “cochlea” ?
organ of hearing
describe the makeup of the cochlea :
- hard-walled
- fluid-filled chamber
- in coiled/shell shape
how many flexible openings that is covered by membrane does the cochlea have ?
2
what are the two openings of the cochela ?
oval window and round window
what does the cochlea do?
takes mechanical energy from the middle ear to electrical impulses
what connects to the oval window of the cochlea ?
the stapes
what is the function of the oval window ?
it receives vibrations from the stapes (middle ear bone) and passes them into the fluid-filled cochlea
what is the function of the round window ?
it helps release pressure by moving in the opposite direction of the oval window
what is the basilar membrane of the inner ear ?
The basilar membrane is in the cochlea and vibrates in response to sound. These vibrations activate hair cells, which send signals to the brain for hearing
describe the structure of the basilar membrane :
- runs the length of the cochlea (base to apex)
- around 36 mm long
what is the cochlea (basilar membrane) covered with ?
cilia (tiny hair cells)
around how many ciliar are there in a healthy human cochlea ?
20,000
how are the cilia’s placed in rows ?
one row of inner and three rows of outer hair cells
what connects to cilia hair cells ?
auditry nerve