The Ear - B Davis Lec 1

Question 1

function of auricle

Answer 1

sound collection and localization

Question 2

sensory innervation to concha

Answer 2

auricular branch of CN X

Question 3

sensory innervation to anterior aspects including tragus

Answer 3

auriculotemporal nerve (V3)

Question 4

sensory innervation to variable, small distribution pattern

Answer 4

posterior auricular branch of CN VII

Question 5

sensory innervation to posterior aspect of auricle aka lateral surfaces of lobule, helix, and anti-helix

Answer 5

Great Auricular Nerve (branch of cervical plexus)

Question 6

sensory innervation to posterior aspect of auricle aka medial surfaces of lobule, helix, and anti-helix

Answer 6

Lesser Occipital Nerve (branch of cervical plexus)

Question 7

innervation to external ear canal

Answer 7

auriculotemporal nerve (V3) and CN X

Question 8

innervation to internal tympanic membrane

Answer 8

CN IX

Question 9

what is the boundary between the external and middle ear

Answer 9

tympanic membrane

Question 10

the tympanic membrane is anchored to the

Answer 10

manubrium of malleus

Question 11

the middle hear houses:

Answer 11

3 tiny ossicles
chorda tympani (VII)
tensor tympani M
stapedius M
tympanic plexus (IX)

Question 12

boundaries of middle ear

Answer 12

floor (inferior): tympanic portion of temporal bone
anterior: auditory/eustachian tube
lateral: tympanic membrane
posterior: mastoid air cells
medial: promontory of inner ear
roof (superior): tegmen tympani

Question 13

the middle ear develops as an out-pocketing of the _________ , and retains this connection via the ______________-

Answer 13

pharynx , eustachian tube

Question 14

Middle Ear: anterior communication

Answer 14

Eustachian tube to nasopharynx

Question 15

Middle Ear: posterior communication

Answer 15

mastoid antrum

Question 16

Middle Ear: medial communication –> oval window

Answer 16

footplate of stapes ; scala vestibuli

Question 17

Middle Ear: medial communication –> round window

Answer 17

pressure release from scala tympani

Question 18

the internal surface of tympani membrane is supplied by the ____________ from __________-

Answer 18

tympanic plexus ; CN IX

Question 19

The tympanic nerve from CN IX is composed of

Answer 19

preganglionic parasympathetic and somatic sensory fibers

Question 20

the tympanic nerve continues through the plexus to enter the cranial cavity as the

Answer 20

lesser petrosal nerve

Question 21

the lesser petrosal nerve leaves through the

Answer 21

foramen ovale

Question 22

the lesser petrosal nerve synapses at the

Answer 22

otic ganglion

Question 23

lesser petrosal nerve postganglionic parasympathetic fibers hitchhike on the ____________ to innervate the ___________

Answer 23

auriculotemporal nerve (V3) ; parotid gland

Question 24

what function do the preganglionic parasympathetic fibers have in the middle ear cavity

Answer 24

none

Question 25

function of the ossicles

Answer 25

levers to magnify sound vibrations from the tympanic membrane to oval window of middle ear

Question 26

the ossicles develop from which arches

Answer 26

1st and 2nd

Question 27

stapes transmits sound waves from the ___________ to the __________ via the oval window

Answer 27

middle ear ; inner ear

Question 28

the malleus does what when the membrane receives sound waves

Answer 28

vibrates

Question 29

the incus transfers vibrations from the

Answer 29

malleus to stapes

Question 30

the stapes receives vibrations from

Answer 30

incus

Question 31

the stapes transfers vibrations via the footplate of the __________ of the ____________

Answer 31

oval window ; inner ear (scala vestibuli)

Question 32

the facial nerve passes through the internal acoustic meatus with CN

Answer 32

VII

Question 33

the geniculate ganglion houses what neuron bodies

Answer 33

1st order sensory neuron bodies

Question 34

what nerve branches at the geniculate ganglion

Answer 34

greater petrosal nerve

Question 35

the greater petrosal nerve carries what fibers and towards what ?

Answer 35

preganglionic parasympathetic fibers ; ptergopalatine ganglion

Question 36

the facial nerve exits the base of the skull through the

Answer 36

stylomastoid foramen

Question 37

what 2 nerves branch off the facial nerve in the facial canal

Answer 37

nerve to stapedius chorda tympani

Question 38

the chorda tympani passes between the

Answer 38

incus and malleus

Question 39

the chorda tympani carries what fibers

Answer 39

taste fibers (anterior 2/3 of tongue) preGPS fibers to submandibular ganglion

Question 40

the chorda tympani merges with what nerve

Answer 40

the lingual nerve

Question 41

the tensor tympani muscle does what

Answer 41

dampens excessive vibrations

Question 42

the tensor tympani is innervated by the

Answer 42

CN V3

Question 43

the stapedius muscle is innervate by

Answer 43

CN VII

Question 44

the stapedius muscle does what

Answer 44

restricts movement dampens vibration from loud noise

Question 45

lesions that paralyze either the tensor tympani muscle or stapedius muscle can result in what

Answer 45

hyperacusis aka hypersensitivity to sound

Question 46

the bony labyrinth is filled with what fluid

Answer 46

perilymph

Question 47

the perilymph drains into the subarachnoid space via

Answer 47

the cochlear aqueduct

Question 48

the oval window is occupied by

Answer 48

stapes footplate

Question 49

the oval window receives vibrations into

Answer 49

scala vestibuli

Question 50

the round window dissipates vibrations from

Answer 50

scala tympani

Question 51

the membranous labyrinth contains what fluid

Answer 51

endolymph

Question 52

endolymph drains into a sac in the subarachnoid space via the

Answer 52

vestibular aqueduct

Question 53

the membranous labyrinth contains what 2 receptor organs for hearing and balance

Answer 53

cochlea and vestibular apparatus

Question 54

the scala vestiboli and scala tympani communicate with one another at the

Answer 54

helicotrema

Question 55

the vestibular apparatus is a region of membranous labyrinth for detection of

Answer 55

balance position movement

Question 56

the inflated region near the cochlea in the vestibular apparatus houses the ______ and _______-

Answer 56

utricle and saccule

Question 57

the utricle monitors what kind of balance

Answer 57

static balance - horizontal acceleration

Question 58

the saccule monitors what kind of balance

Answer 58

static balance - vertical acceleration

Question 59

the semicircular canals monitor what kind of balance

Answer 59

kinetic (angular movement of head on the APL planes aka rotational)