Hearing Flashcards
Three sections of ear
outer, middle, inner
the structure that we normally think of as the ear, on the outside
Pinna/auricle
two purposes of pinna
funnel sound energy and aiding localization of sound in space
curled outer part of pinna
Helix
two ends of the superior part of antihelix after it splits in two
Crura of antihelix
entrance to ear canal
concha
another name of ear canal
External auditory meatus (EAM)
Medial point of auricle, when pressed down can cover the concha
Tragus
most inferior dangly bit of auricle
lobule
another name for eardrum
Tympanic membrane (TM)
another name for ear wax
Cerumen
Protects TM from dirt and insects via hairs and cerumen
ear canal
marks boundary between outer and middle ear
TM
what are the three layers of the tympanic membrane made of?
Outer = epithelial from EAM
Middle = fibrous tissue, makes structure (actually 2 layers)
Inner = lining of middle ear
portion of TM on the bottom that reflects light back to doctor
Cone of light
“tucking” point of helix
Crus of helix
what are the names of the three layers of the TM?
cuticular (outer)
fibrous (middle)
mucous (inner)
bones of ear known as
ossicles
Three bones that form ossicular chain
Malleus
Incus
Stapes
what is the purpose of the ossicular chain?
transmit acoustic energy to inner ear
malleus bone
middle ear bone nicknamed anvil
incus
incus
this middle ear bone is nicknamed “stirrup”
stapes
Ossicular chain held in place by
ligaments
Two muscles of inner ear (smallest in body)
Stapedius
Tensor tympani
what is the function of the stapedius muscle?
rotates stapes to stiffen ossicular chain
the tympanic muscles ____ ossicular motion to protect the ears
inhibit
stapes
what is the function of the tensor tympani muscle?
pull malleus to stiffen ossicular chain
activation of the stapedial muscle turns on after 85 dB, and is known as the
acoustic reflex
in the middle ear, what contains the footplate of stapes?
oval window
in middle ear, what is inferior to oval window, bulge made by cochlea
promontory
in middle ear, what is inferior to promontory, sealed by secondary tympanic membrane
Round window
in middle ear, bulge between lateral semicircular canal and oval window
Prominence of facial nerve
path for O2 to get to middle ear, connected to nasopharynx
Auditory/Eustachian tube
skull bone behind the ear, opposite of jaw
Mastoid process
can reach floor of middle ear, infection can be a problem
mastoid air cells
inflammation of mastoid bone, can lead to hearing loss, vestibular dysfunction, tinnitus, brain infection and death
Mastoiditis
what are two functions of the mastoid air cells?
1) help keep bone light
2) helps transmit sound to brain
what are the two functions of the oval window?
1) house footplate of stapes
2) communicate point between scala vestibuli and middle ear
what is the function of the round window?
communicate/connection point between scala tympani and middle ear
Inflammation of the middle ear; common in children because their Eustachian tubes collect fluid more easily
otitis media
what are the two labyrinths of the inner ear?
osseous and membranous
The osseous labyrinth contains the ____ ____, and inside them are the membranous ____ ___.
semicircular canals; semicircular ducts
The function of the semicircular canals/ducts is to
help with balance and our sense of bodies in space
In between the semicircular canals and the cochlea is the
vestibule
The cochlear canal is coiled around the central __ bone
modiolus (hub of a wheel)
What are the three channels of the cochlea from superior to inferior?
scala vestibuli
cochlear duct (scala media)
scala tympani
within the membranous inner ear, what are the two sections?
vestibular labyrinth (in displacer beast part)
cochlear labyrinth
Scala vestibuli and scala tympani meet here at the apex of the cochlea
helicotrema
the vestibular labyrinth’s two membranous sacs that serve as vestibular receptors
US from Baldur’s Gate
utricle
saccule
what are the two membranes that are on the ends of the cochlear duct, and sandwich the Organ of Corti between them
Reissner’s membrane
Basilar membrane
the hearing organ at the center of the cochlea
Organ of Corti
In the Organ of Corti, these hair cells have stereocilia on the top, are in a single row, and are teardrop shaped
inner hair cells
In the Organ of Corti, these hair cells have stereocilia on the top, are 4 rows and are test tube-shaped
outer hair cells
this bundle of nerves is the way we hear background noise; connected to hairs in inner ear
Olivocochlear bundle
the small membrane over the Organ of Corti that the hairs brush up against when the organ moves
tectorial membrane
which cranial nerve is the auditory nerve?
VIII - vestibulocochlear
ear deformity with small auricle - common in Down syndrome
Microtia
what is the function of the middle ear?
increases pressure by decreasing area - makes it possible for sound to go from air to water
what is the function of the inner ear in regards to hearing?
processes pitch, frequency and volume
the part of the auditory system that sends the signals to the brain
auditory pathway
the part of the auditory system that interprets the auditory signal
cerebral cortex
gelatinous mass inside the ampullae of the semicircular ducts that helps with dynamic movement
cupula
which part of the ear inner is responsible for maintaining static equilibrium?
otoliths
another name for the utricle and saccule
otoliths
anatomical term for hearing
audition
What are the four language goals for children with hearing impairments?
NPR SV
Expand vocab
Enhance syntax and pragmatics
Develop narrative skills
Literacy (reading)
what are the three speech goals for children with hearing impairments?
VIP
-Increase amount of vocalizations
-Expand phonetic and phonemic repertoire
-Increase speech intelligibility
this type of equilibrium is also known as the “righting reflex” and helps us not to fall
static equilibrium
this type of equilibrium helps keep us balanced when we or the environment around us is moving
dynamic equilibrium
where are the ampullae of the semicircular ducts?
the balls at the end of the displacer beast’s tentacles
4 important membranes of the ear and their location
1) tympanic membrane - barrier outer and middle ear
2) tectorial membrane - Organ of Corti
3) Reissner’s membrane - inner, connected to Basilar, divides vestibuli from cochlear duct
4) Basilar membrane - inner, connected to Reissner, divides cochlear duct from scala tympani
The tympanic membrane is completely developed in utero by ___
18 weeks
hearing begins in the womb at ___
23-24 weeks
the ossicles are fully developed by ___
birth
the hearing mechanism in innervated by the ___ cranial nerve, which splits to form the ___ and ___ nerves
8th (vestibulocochlear); vestibular, cochlear
