Auditory Flashcards
What are the three bones of the ear
malleus
Incus
stapes
is the eardrum a part of the inner or outer ear
outer ear
what is the function of the tensor tympani and stapedius muscles
to dampen the intensity of sound
what are the two muscles that dampen the intensity of sound
tensor tympani muscle
stapedius muscle
where is the oval window in the ear
deep to the stapes
what is the other word for the pinna
auricle
what is the other name for the eardrum
tympanic membrane
what do you call the bones in the ear
ossicles
what is the membranous sacs in the ear filled with
endolymph
the fluid inside the membranous sacs of the ear is rich in what
potassium
what are the two structures in the vestibule
utricle
saccule
what is the function of the utricle and saccule
encode the orientation of the head relative to the axis of the body
what part of the vestibular system specifically are the utricle and saccule in
the static vestibular system
how many semicircular canals are there in the inner ear
3
what is the role of the semicircular canals
encode movement for all the planes of the head
name of equilibrium receptors in utricle/saccule
maculae
what is the vestibule
egg shaped cavity in the inner ear
what is the name of the swollen end of each semicircular canal
the ampulla
what type of receptors does the ampulla house
equilibrium receptors
what is the cristae ampullaris
a region in the ampulla that houses equilibrium receptors
what receptors respond to angular movements of the head
the equilibrium receptors in the ampulla
name of the spiral bony structure in the ear
cochlea
what is the organ inside the cochlea
the corti
what is the corti
the hearing receptor
bony pillar that the cochlea coils around
modiolus
what cochlear chamber contains receptors that transduce sound info into electrochemical signals
scala media
what are the three chambers of the cochlea
scala vestibuli
scala media
scala tympani
where does the scala tympani terminate
the round window
what is the fluid in the scala tympani and vestibuli
perilymph
what is the fluid in the scala media
endolymph
what is another name for the scala media
cochlear duct
what is the importance of continuity of fluid through the cochlea
allows vibrations to be passed through
what is perilymph rich in
sodium chloride or something lol
vibrations in which membrane carry sound into the corti
basilar membrane (floor of scala media)
in what order does sound reach the three canals in the cochlea
scala vestibuli, then tympani and then the cochlear duct
sound is composed of areas of (2)
rarefraction
compression
sound is represented by what type of wave
a sine wave (think sound, sine)
what property of sound is measure in decibels
amplitude
what is the name for the subjective interpretation of sound intensity
loudness
what is the name for the number of waves that pass a given point in a given time
frequency
what is the perception of different frequencies
pitch
what is another way of describing a hertz
cycle per second
what is another name for the ear canal
external acoustic meatus
what are the receptive cells in the ear
hair cells
what stimulates the cochlear nerve
moving hair cells
what sends impulses to the brain
cochlear nerve
why do different frequencies vibrate the basilar membrane in different places
because at the base it has short stiff fibers, but it has long floppy fibers at the end that dont require as much force to move
sounds with frequencies below hearing levels go around the ________ and do not excite hair cells
helicotrema
sounds in the hearing range go through the ________
cochlear duct
what is another name for the helicotrema
the apex
what is the apex also known as
the helicotrema
vibration goes in the _____ window and ends at the _____ window
oval; round
what is another name for the hair cells
the stereocilia
in the corti, afferent fibers of the cochlear nerve attach to
the base of hair cells
what are stereocilia
hair cells
what membrane do the stereocilia touch
the tectorial membrane
what channels open when cilia bends
mechanically gated calcium and potassium
when cilia is bent, what is caused (2)
a graded potential and the release of a neurotransmitter
what does the released neurotransmitter do
causes cochlear fibers to transmit impulses to the brain
what is the difference between the inner and outer hair cells
inner hair cells are sensory
outer hair cells improve hearing sensitivity
hair cells have numerous ____
hairs lol
what are the hair cells linked together by
tip links
what is the typical neurotransmitter released when a graded potential occurss
glutamate
what specifically opens the mechanically gated ion channels
when inner hair cells bend, the tension on the tip links opens the channels
where is pitch perceived
primary auditory cortex
where is loudness perceived
cochlear cells/ number of cells stimulated
localization is perceived by
the superior olivary nuclei
where are the two maculae
one in the utricle
one in the saccule
what moves the hair bundles in the vestibular system
gravity acting on the otolithic membrane
utricular hairs respond to ________ movement
horizontal
saccular hairs respond to _______ movement
vertical
vestibular receptors monitor _______ equilibrium
static
semicircular canal receptors monitor ___________ equilibrium
dynamic
where is the otolithic membrane located
in the maculae
otoliths are composed of
calcium carbonate
action potentials in the vestibular nerve _______ when movement is towards kinocilia
increase
action potentials in the vestibular nerve _______ when movement is away form kinocilia
decrease
what happens when hairs in the maculae bend towards the kinocilium
the hair cells depolarize
what happens when hairs in the maculae bend away from the kinocilium
the hair cells hyperpolarize
the crista ampullaris responds to ______ movements
angular
where are crista located
in the ampulla of semicircular canals
what are the three modes of input for balance and orientation
vestibular receptors
visual receptors
somatic receptors
