Auditory System Flashcards
The external ear is basically made up of these 3 structures:
auricle, external acoustic meatus, tympanic membrane
The middle ear is basically made up of these 4 structures:
inner ear bones, oval window, round window, auditory tube (eustatian tube)
The oval window is _______ in relation to the round window
superior
The ______ of the external ear is made up of stratified squamous epithelium (keratinized), hair follicles, and elastic cartilage (with elastic fibers)
auricle
The auricle is made up of these 2 major structural areas:
perichondrium peripherally, elastic cartilage interior
The ______ of the external ear is made up of stratified squamous epithelium, hair follicles, ceruminous glands, elastic cartilage, and temporal bone
external acoustic meatus
Ceruminous glands of the external acoustic meatus are found ______ to the hair follicles
deep
The main structural components of the external acoustic meatus are these 2:
elastic cartilage, temporal bone
The epithelium of the ________ of the middle ear is pseudostratified respiratory epithelium
auditory tube
The 2 identifying characteristics of the _______ of the middle ear are pseudostratified respiratory epithelium and numerous goblet cells
auditory tube
The main structural components of the auditory tube of the middle ear are:
bone and fibrocartilage
Otitis media, inflammation of the middle ear, affects the _________, and can cause ________, ______, or _______
tympanic membrane, facial nerve palsy, ruptured tympanic membrane, scarred auditory ossicles
The external portion of the tympanic membrane is called ________ and is lined with ________ epithelium
the cuticular layer, stratified squamous epithelium
The external portion of the tympanic membrane (cuticular layer) is derived from ______
ectoderm
The middle layer of the tympanic membrane is called the ______ and is made up of _______. It is derived from _________
fibrous layer, collagen II and III, mesoderm
The inner layer of the tympanic membrane is called the ________ and is made of _______ derived from ______
mucous layer, cuboidal cells, endoderm
These 3 nerves pass through the internal acoustic meatus:
vestibulocochlear nerve (CN VIII), facial nerve (CN VII), vestibular nerve
The _______ surrounds the bony modiolus and houses the spiral ganglion
spiral lamina
The internal spaces of the oval window, round window, and cochlear duct are these 3 respectively:
They are all filled with perilymph
scala vestibuli, scala tympani, scala media
The ______ is a collection of neuronal cell bodies in internal ear of neurons with axons in VIII
spiral ganglion
The dendrites of the _______ synapse in the organ of corti
spiral ganglion
The internal ear is supplied by the _______ artery, a branch of _______
labyrinthine artery, AICA
In the image of organ of corti, the ________ is just superior to the vestibular membrane, and the ________ is just inferior to the basilar membrane
scala vestibuli, scala tympani
The _______ is the membrane that the organ of corti is parallel to
basillar membrane
In the super close-up histological image of the organ of corti, the cell bodies of CN VIII neurons are ______ of the organ of corti, and look like ______
left, grapes
In the totally green close-up histological image of the organ of corti, the brighter areas are:
CMV tagged with fluorescent protein
_____ is the leading non-genetic cause of hearing loss for infants born in the U.S.
cytomegalovirus (CMV)
The ________ transmits sound vibrations to the outer hair cells of the organ of corti
tectorial membrane
The CNS, PNS, epidermis, and connective tissues of the head are derived from _______
ectoderm
The muscles, connective tissues of the body and limbs, vessels, and viscera are derived of ______
mesoderm
The epithelium of the GI tract, respiratory system, and urinary bladder are derived from ______
endoderm
The middle ear is an evagination of the ________
respiratory system
The _______ forms from cells of the otic vesicle wall and migrating neural crest cells
statoacoustic ganglion (eventually forms the vestibular and cochlear ganglia)
The dorsal component of the otic vesicle forms the ______, _______, and _______
utricle, semicircular ducts, endolymphatic duct
The ventral component of the otic vesicle forms the _______ and _______
saccule, cochlear duct
The _______ surrounding the cochlear duct eventually separates it from the scala vestibuli and scala tympani
mesenchyme
The mesenchyme of the cochlear duct separates the duct from the scala vestibuli and scala tympani at ____ weeks
10 weeks
By 5 months the _______ and ______ form in the cochlear duct
neuroepithelial cells, tectorial membrane
The ______ and ______ middle ear ossicles are formed from arch 1
malleus, incus
The ______ layer of the tympanic membrane is derived from ectodermal epithelium
cuticular layer
high frequencies activate near the _____ of the cochlea, low frequencies activate near the ______
base, apex
During development, BMP7 is higher at the _____ of the cochlea (where low frequencies are sensed)
apex
______ frequencies are sensed far away from the stapes and oval window
low
The ______ is the time between two peaks of a pure tone
period
The _______ is the distance a sound wave travels during a period
wavelength
The interaural time difference (D2-D1)/V can be used to localize _________
low-frequency sounds
The interaural (difference between sounds detected at either ear) intensity difference is used to localize _______
high-frequency sounds
The ________ is included in the organ of corti and the supporting cells are called _______
tectorial membrane, phalangeal cells
There are 3-4 rows of _______ cells as part of the organ of corti, and only 1 row of ______ cells
outer hair cells, inner hair cells
_______ , part of the organ of corti, cannot regenerate
hair cells
Cell bodies of cochlear afferent neurons are in the ________
spiral ganglion
________, part of the organ of corti, are unmyelinated
cochelar afferent neurons
The ______ is responsible for maintaining the ionic composition of endolymph through selective secretion and absorption of ions
stria vascularis
The endolymph of the _______ is similar to intracellular fluid
scala media
The perilymph of the _________ and ________ is similar to cerebrospinal fluid, it has high concentration of Na+ for neuron viability
scala vestibuli, scala tympani
The perilymph of the scala vestibuli and scala tympani is also found in the ______ and _______
tunnel of corti, basal end of hair cells
________ between hair cells separates endolymph from perilymph
tight junctions
______ cells in organ of corti are supporting cells of hair cells
phalangeal cells
______ are the sensory receptors for sound stimuli
inner hair cells
________ alter the mechanics of basilar membrane of organ of corti by changing length
outer hair cells
_______ of organ of corti increase the sensitivity of cochlear afferent neurons conveying information
outer hair cells
The _______ of the organ of corti is made up of the processes of phalangeal cells
reticular lamina
As hair cells depolarize, ________ channels open at the base of these hair cells and glutamate is released
voltage-gated calcium channels
The ______ membrane is found between the tectorial membrane and rest of organ of corti
reticular membrane
The bipolar neurons of the spiral ganglion are:
Type I cochlear afferent neurons and Type II cochlear afferent neurons
________ afferent neurons respond to a narrow frequency range (high precision)
Type I cochlear afferent neurons
Most of the afferent neurons in the cochlea are:
Type I cochlear afferent neurons
_______ respond to a wide frequency range (low precision)
Type II cochlear afferent neurons
_______ neurons synapse with over 10 outer hair cells each
type II cochlear afferent neurons
Both increased firing of and increased number of firing cochlear afferent neurons increases _______
intensity of sound
lateral olivocochlear efferent neurons synapse with ________
type I cochlear afferent neurons
medial olivocochlear efferent neurons synapse with _______
outer hair cells
The ________ of a type I cochlear afferent neuron is the frequency it detects with the lowest threshold intensity
characteristic frequency
Sound detected by cochlear afferent neurons with cell bodies in spiral ganglion are transmitted via the _______ nerve to the ________
vestibulocochlear nerve, ipsilateral dorsal and ventral cochlear nuclei
The cochlear nuclei reside in the ________ of the medulla
restiform body
Second order neurons of the auditory pathway have their cell bodies in ________
cochlear nuclei of the restiform body of the medulla
Axons of cochlear nuclei project to the ________ and _________ of the ______
trapezoid, lateral lemniscus, pons
Neurons in cochlear nuclei have axons that project to the _______ and to the _______
trapezoid body, lateral lemniscus
Axons of second order neurons of the auditory pathway that travel in the lateral lemniscus ____________
project bilaterally to left and right inferior colliculi of the midbrain
Axons in both the ______ and the _______ project bilaterally to the inferior colliculi of the midbrain
trapezoid body, lateral lemniscus
Cell bodies of neurons in the inferior colliculi project directly to the ______ and also send axons laterally through the ________ to synapse on the ________
ipsilateral MGN of the thalamus, commissure of inferior colliculus, contralateral MGN of the thalamus
______ division of the MGN of thalamus is involved in complex feature detection of sounds
anterior division
The _______ division of the MGN of thalamus is involved in conveying information about moving or novel stimuli
posterior division
Axons of the MGN of thalamus project to the primary auditory cortex through the _________ as auditory radiation
sublenticular limb of the internal capsule
The area where axons of MGN travel is supplied by _________ (artery)
lenticulostriate arteries
The MGN of the thalamus is adjacent to the ________ and the _______
pulvinar nucleus, lateral geniculate nucleus
The _______ artery supplies the MGN as well as most of the posterior thalamus
thalamogeniculate artery of PCA
The _______ and _______ of the thalamus send projections to the primary somatosensory cortex (3,1,2)
VPL, VPM
The _____ of the thalamus projects to the primary somatomotor cortex (4)
VL
The VL of the thalamus is supplied by the ________ artery
thalamoperforating artery
The VPL and VPM of the thalamus are supplied by the __________ artery
thalamogeniculate artery
The primary auditory cortex is Brodmann area _____
41
The primary auditory cortex includes the ________ and _________
insula, transverse temporal gyri
The primary auditory cortex is a __________ area and receives axons from the ________ of the MGN
heterotypical granular area, anterior division
The primary auditory cortex (Brodmann area 41) is located in the _________
anterior transverse temporal gyrus of Heschl
The secondary auditory cortex receives axons from the _________
posterior division of MGN
The secondary auditory cortex is Brodmann area ____
42
The secondary auditory cortex is located in the _________
posterior transverse temporal gyrus of Heschl
The primary auditory is ______ in relation to the secondary auditory cortex and is directly adjacent to the ______
anterior, central sulcus
The _____ is anterior to the primary and secondary auditory cortices
insula
The auditory association cortex are Brodman areas:
22, 39, 40, 44, 45
The auditory association cortex is located in the _________ and contains _________
superior temporal gyrus, Wernike’s area
Damage to the ________ gyrus affects language comprehension (SPEECH)
superior temporal gyrus
The auditory association cortex (brodmann areas 39 and 40) is located in the __________ of _______
angular and supramarginal gyri of parietal lobe
Damage to __________ affects language comprehension (reading and writing)
angular and supramarginal gyri of parietal lobe
The angular and supramarginal gyri of parietal lobe are Brodmann area(s):
30, 40
The auditory association cortex of Brodman areas 44 and 45 is located in the _______
inferior frontal gyrus
The _________ projects to the inferior frontal gyrus portion of the auditory association cortex
arcuate fasciculus
Damage to the inferior frontal gyrus affects the _______ and causes _____________
Broca’s area, nonfluent speech with comprehension spared
The inner ear and cochlear nuclei are supplied by the _______ artery
labyrinthine artery (AICA)
The inferior colliculus is supplied by the _______ artery
quadrigeminal (branch of SCA) artery
The primary auditory cortex and auditory radiation are both supplied by the _______
MCA inferior trunk
The ________ supplies the inferior temporal optic radiation (including Meyer’s Loop), the primary auditory cortex, and auditory radiation
MCA inferior trunk
The descending pathway from the auditory cortex projects to the _________ which projects to the ________
inferior colliculus, superior olivary complex
The superior olivary complex contains _________ neurons and _______ neurons
lateral olivocochlear efferent neurons, medial olivococohlear efferent neurons
Lateral olivocochlear efferent neurons project __________
ipsilaterally to type I cochlear afferent neurons
medial olivocochlear efferent neurons project ___________
bilaterally to synapse directly on outer hair cells
The monaural pathway of auditory pathway is:
routed to the contralateral side
The __________ is handled by central pathways that compare differences between sounds at both ears
binaural pathway
The _________ pathway contributes to complex feature detection and only has one decussation at the ________
monaural pathway, posterior acoustic stria
The posterior acoustic stria only project directly from the ________
anterior and posterior cochlear nuclei in the medulla
The binaural pathway decussates from only the anterior cochlear nucleus at the _______
trapezoid body in the pons and medulla
After decussation, the monaural pathway travels through the _______ to the inferior colliculus
lateral lemniscus
After decussation, the binaural pathway travels in the _________ and the _______ before reaching the inferior colliculus
superior olivary nuclei, lateral lemniscus
The posterior acoustic stria is located in the ______
medulla
The trapezoid body crosses the ________ in the pons
facial nerve
The auditory cortex is at the level of the ________
corpus callosum
high tones are sensed at the _____ of the basilar membrane in cochlea, while low tones are sensed at the ______
base, apex
high tones are sent to the ______ primary auditory cortex, while low tones are sent to the ________ side
medial, lateral
Interaural time difference is important for localizing ______ sounds
low-frequency
interaural intensity difference is important in localizing _______ sounds
high-frequency
The _______ receives bilateral auditory input and is important for localizing sounds
superior olivary nuclei
The afferent limb of the reflex that orients the head, eyes, and body to novel sounds includes these 4 structures:
lateral lemniscus, inferior colliculus, secondary auditory cortex, superior colliculus
The efferent limb of the reflex that orients the head, eyes, and body to a novel sound:
tectobulbospinal neurons from superior colliculus activate PPRF and reticular formation
The _______ is activated for orientation of the head during the reflex that orients the head to novel sound
sternocleidomastoid muscle
The acoustic startle reflex afferent limb uses the _______ cortex
secondary auditory cortex
The afferent limb of the acoustic startle reflex involves the lateral lemniscus, _________, ________, and finally the superior colliculus
inferior colliculus, secondary auditory cortex
