Physiology of Hearing Flashcards
describe what sound is
a pressure wave caused by oscillating molecules they are set in motion by vibration
what dictates pitch and intensity of a sound
pitch = frequency of vibration intensity = amplification of vibration
describe how the external ear aids hearing
it is shaped to receive sound
what part of the ear is the amplification mechanism
the middle ear, specifically the ossicular chain
describe the amplification mechanism of the ear/hearing
ossicular chain acts as piston or lever arm with varying efficiency depending on frequency of sound transmitted
what part of the ear is the receiver/transducer
the inner ear
describe the receiver/transducer mechanism of the ear/hearing
curved spiral lamina
coiled tubes of fluid, scala media suspended between scala tympani and scala vestibuli
what liquid is found in the scala media and what liquid is found in the scala tympani and vestibuli
scala media = endolymph
scala tympani and vestibuli = perilymph
what are the 2 openings of the cochlea to the middle ear
the oval window and the round window
what is the function of the oval and round windows
permit transmission of pressure wave in enclosed canal and vibration of the basilar membrane
what is the functional unit of the organ of corti
the inner hair cells, they sense vibrations
where is the primary auditory complex
left posterior superior temporal gyrus
what are the functions of the eustachian tube
ventilation pathway for the middle ear mucosa, also equalises ear pressure
what is the resting state of the eustachian tube and what is it opened by
resting state is closed
opened by tensor veli palatini and levator palatine muscles
describe the action of the organ of corti when basilar membrane(inner hair cells specifically) is stimulated
organ of corti depolarises and fires, stimulating CN VIII and then the central pathways
