Physiology: Hearing and Balance Flashcards
what is sound?
a pressure wave caused by oscillating molecules
what dictates the pitch of a sound?
frequency of oscillations
what dictates the volume of a soudn?
amplitude
what is the range of frequencies that can be heard?
20-20,000
what is the role of the external ear in hearing?
receives sound
what is the role of the middle ear in hearing?
amplifies sound
what is the role of the inner ear in hearing?
receives and transduces sound
what in the ear works to amplify a sound?
the ossicular chain in the middle ear
what two things make up the cochlea?
curved spiral lamina
three coiled tubes of liquid
what are the three coiled tubes of liquid in the cochlea called?
scala media
scala tympani
scala vestibuli
what are the two openings of the cochlea in the middle ear?
oval window
round window
what do the windows of the cochlea allow?
transmission of the pressure wave
vibration of the basilar membrane
what effect does vibration of the basilar membrane have?
vibrates the hair cells
generates an AP
what is the functional unit of the organ of corti?
the hair cell
what route is taken by AP’s generated by hair cells?
CN VII to the cochlear nucleus
pass to the primary auditory cortex
where is the primary auditory cortex found?
the left posterior superior temporal gyrus
what acts as the ventilation system for the middle ear mucosa?
eustachian tube
what is the cartilage portion of the eustachian tube like at rest?
closed
what muscles can open the eustachian tube?
tensor veli palatini
levator palatine muscles
what does dysfunction of the eustachian tube lead to?
negative middle ear pressure
what are the five vestibular end organs?
three semi circular canals
utricle
saccule
what are the longest hair cells called?
kinnocilium
what are the shortest hair cells called?
sterocilia
