Exam 5 - Hearing Flashcards
(145 cards)
1
Q
Three Parts of Ears
A
- Outer
- Middle
- Inner
2
Q
These parts of ears involved with hearing
A
outer + middle ear
3
Q
These part(s) associated in both hearing and equilibrium
A
Inner ear
4
Q
Receptors for hearing and balance Respond to separate/the same stimuli
A
Separate
5
Q
Receptors for hearing and balance are activated dependently/independently
A
Independently
6
Q
The ___ (pinna) is composed of the Helix (rim) and the Lobule (earlobe)
A
Aurical
7
Q
The ___ ___ ___ leads to the middle ear
A
external acoustic meatus
8
Q
Short, curved tube filled with ceruminous glands; secretes earwax
A
External acoustic meatus
9
Q
Medial border is the ___ ___ (eardrum), which serves as the boundary between the outer and middle ears
A
Tympanic Membrane
10
Q
Thin connective tissue membrane that vibrates in response to sound waves
A
Tympanic Membrane
11
Q
Transfer sound energy to the middle ear ossicles
A
Tympanic Membrane
12
Q
Region of ear where medial boundary is oval window, lateral border is tympanic membrane
A
Middle ear
13
Q
Small, air-filled mucosa-lined cavity
A
Middle Ear = Tympanic Cavity
14
Q
connects the middle ear to the nasopharynx
A
Eustachian (auditory) tube
mid ear
15
Q
Equalizes pressure in the middle ear cavity with the external air pressure
A
Eustachian (auditory) tube
mid ear
16
Q
Swallowing and yawning open this tube, allows equalization
A
Eustachian (auditory) tube
mid ear
17
Q
Cold/ear infection; can’t equalize pressure, the tympanic membrane bulges
More difficult in babies/toddlers since this tube is more parallel
A
Occlusion of Eustachian tube
middle ear
18
Q
Three small bones in the middle ear
A
Ossicles
= malleus, incus, and stapes
middle ear
19
Q
Suspended by ligaments and joined by synovial membranes
A
Ossicles
= malleus, incus, and stapes
middle ear
20
Q
Transmit vibratory motion of the eardrum to the oval window (vestibule of inner ear)
A
Ossicles
= malleus, incus, and stapes
middle ear
21
Q
mucles contract reflexively (CN VIII & inferior colliculi) in response to loud sounds to prevent damage to the hearing receptors of the cochlea
A
Tensor tympani and stapedius mucles
Middle Ear
22
Q
Bony labyrinth which contains twisting channels which work their way through the temporal
bone (petrous region) and filled with perilymph
A
Inner Ear
23
Q
Auditory ossicles transmit the vibratory motion of the eardrum to the ___ ___ of the ____ (stapes)
A
oval window of the vestibule
24
Q
Ossicles are suspended by ___ and joined by ____ membrane
A
ligaments; synovial membrane
25
Recall: Cranial Nerve ___, listed as an "S" actually has a very small motor component; motor component is reflex loop to inferior colliculi and back to the muscles
VIII
26
Bony labyrinth which contains twisting channels which work their way through the temporal
bone (petrous region)
Inner Ear
27
filled with perilymph
Inner Ear
28
Contains the vestibule (entrance), the semicircular canals, and the cochlea
Inner Ear
29
Bony labyrinth contains a matching membranous labyrinth) filled with
Endolymph
| Inner Ear
30
The central egg-shaped cavity of the bony labyrinth
Vestibule
| Inner Ear
31
Suspended in its perilymph are two membranous sacs
Vestibule
| Inner Ear
32
Membranous sacs that extends into the semicircular canals
Utricle
33
Membranous sacs in Vestible that extends into the Cochlear duct
Saccule
34
Utricle and Saccule house equilibrium receptors regions called
Maculae
35
Maculae respond to
gravity and changes in the position of the head
36
Maculae also maintain static equilibrium, or
make adjustments to keep balance in the new position
37
Maculae sensory information is transmitted to the brain via the Vestibular branch of
CN VIII
38
Three canals that each define two-thirds of a circle and lie in the three planes of space
Semicircular Canals
39
Continuous with the utricle; each canal lined with membranous semicircular ducts
Semicircular Canals
40
The ___ is the swollen end of each canal and it houses an equilibrium receptor
known as the the___
ampulla; crista ampullaris
41
Responds to the angular dynamic movements of the head (rotation)
Crista Ampullaris
42
Makes adjustments to keep balance during dynamic rotation; maintains ___ equilibrium
Dynamic Equilibrium
| Crista Ampullaris
43
Sensory information is transmitted to the brain via the Vestibular branch of ___ nerve
CN VIII
44
A bony 3-layered, conical, snail-shell spiral chamber that extends from the vestibule
Cochlea
45
A bony 3-layered, conical, snail-shell spiral chamber that extends from the vestibule; looks like a snail shell
Cochlea (Hearing)
46
Three chambers of the cochlear cavity
1) Scala vestibuli
2) Scala media
3) Scala tympani
47
Abuts the oval window, contains perilymph
Scala vestibuli
48
Contains endolymph
Scala media = cochlear duct
49
Terminates at the round window; contains perilymph
Scala tympani
50
These are continuous at the cochlear apex
Scala Tympani and Scala Vestibuli
51
houses the spiral organ of Corti
Scala media
52
hearing receptor with cell hairs = ?
Sterocilia
53
This is the hearing receptor with sterocilia
Spiral Organ of Corti
54
The “floor” of the cochlear duct is composed of the ___, which supports the organ of Corti
basilar membrane
55
The “roof” of the organ of Corti is covered with the stiff gel-like ___; ends of stereocilia are embedded (trapped) in this covering
tectorial membrane
56
The ___ (filled with perilymph) sits below the scala media and terminates at the membrane covered, flexible round window
scala tympani
57
The signals are transmitted along the cochlear branch of Cranial Nerve ___
VIII
58
alternating areas of high and low pressure originating from a vibrating object
Sound
59
radiate outward in all directions; illustrated by a sine wave
Sound waves
60
the number of waves that pass a given point in a given time (Hz)
Frequency
61
intensity of a sound measured in decibels (dB)
Amplitude
62
The distance between two consecutive crests
Wavelength
63
subjective interpretation of amplitude
Loudness
64
Normal range is 0-120 dB (damage at prolonged 100dB +)
Loudness
65
perception of different frequencies
Pitch
66
Normal human range is from 20–20,000 Hz
Pitch
67
The higher the frequency, the ___ the pitch
higher
68
Sound waves vibrate the ___, thus pushing / vibrating the ___ and
subsequently amplifying the pressure
tympanic membrane, ossicles
69
The stapes pushes against the ___, creating fluid waves in the ___
oval window, scala vestibuli
70
The flexible round window bulges outward, allowing fluid to move in ___
waves
71
Sounds in the hearing range pass through the ___, vibrating the ___.
This movement sets up shearing forces that deflect the embedded stereocilia
cochlear duct, basilar membrane
72
Moving hair cells create___potentials which lead to ___Ps
graded, action
73
Sound waves of low/high frequency (> or < 20 Hz; inaudible) do not affect the cochlear duct
-Travel around the apex and therefore do not excite hair cells
low, less than
74
Audible sound waves will/will not vibrate the basilar membrane
-Excite specific hair cells located according to the frequency of the sound
will
75
Higher frequency waves deflect the short and stiff basilar membrane fibers near/far from the
oval window
near
76
Mid and low frequency waves deflect longer basilar membrane fibers further down/up
the cochlea, closer to the apex
further down
77
Age-related stiffening of the joints of the ossicles, so can’t vibrate as fast;
subsequent loss of high frequency hearing
Otosclerosis
78
Bending of the stereocilia embedded in the gel-like tectorial membrane
Excitation of Hair Cells in the Organ of Corti (Spiral Organ)
79
Bending stereocilia:
| 1) Opens ____ gated ion channels
1) Mechanically
80
Bending sterocilia:
| 2) Causes a ___ potential (with subsequent release of the neurotransmitter glutamate)
graded
81
Bending stereocilia:
| 3) ___ travel along the cochlear nerve afferent fibers (at the base of the hair cells)
AP's
82
Transmission of Sound in Ear: Overview
| 1. Sound waves vibrate ___ membrane
Tympanic
83
2. Auditory ossicles vibrate. Pressure is ___
amplified
84
3. Pressure waves created by the ___ pushing on the oval ___ move through the perilymph in the scala ____.
stapes
window
vestibuli
85
4. Sounds in the hearing range go through the cochlear duct, vibrating the basilar membrane and deflecting hairs on inner hair cells. The moving hair cells stimulate transduce to graded potentials that will ultimately send APs along the ___ nerve.
cochlear
86
audible sound waves
20-20,000 Hz
87
stereocilia are embedded in gel-like
tectorial membrane
88
5) Impulses from the choclea pass via the spiral ganglion to the ___ nuclei of the medulla.
cochlear
89
6) Axons will project to and synapse at
a. Superior olivary nucleus (pons/medulla)
| - involved with directional hearing
90
6)) Axons will project to and synapse at
Inferior colliculus
| auditory reflex center
91
7) From there, impulses pass to the ___ cortex via the thalamus
Auditory Cortex
92
Look at p 51 of the powerpoint on hearing
okay
93
Part of brain that
| - provides conscious awareness of sound, including loudness, pitch and direction
Auditory Cortex
94
Part of brain that
- Some (but not all) auditory pathways decussate so that both cortices receive input from both ears
- this is how we "localize" the source of the soundn
Auditory Cortex
95
Part of brain that:
| -Stores memories of sounds
Auditory Association Cortex
96
Multiple ___ regions, including Wernicke's, involved with language ___
cortex; comprehension
97
something hampers sound conduction to the fluids of the inner ear
(e.g. impacted cerumen, perforated eardrum, otitis media [middle ear infection], otosclerosis)
Conduction deafness
98
results from damage to the neural structures at any point from
the cochlear hair cells to the auditory cortical cells
Sensorineural deafness
99
provides a sense of hearing for someone who is profoundly deaf but
has a functioning auditory nerve
Cochlear Implants
100
ringing or clicking sound in the ears in the absence of auditory stimuli
Tinnitus
101
Due to
-cochlear nerve degeneration,
-inflammation of middle or internal ears,
-side effects of aspirin (and many other ototoxic drugs),
-exposure to loud sounds over extended
period of time (concerts, earbud-style headphones with volume too high)
Tinnitus
102
equilibrium receptors in the vestibule and semicircular canals
Vestibular Apparatus
103
(maculae in vestibule) monitor static equilibrium
Vestibular receptors
104
(cristae ampulares) monitor dynamic equilibrium
Semicircular Canal Receptors
105
___ macula in each saccule wall and ___ macula in each utricle wall
One; One
| Static Equilibrium
106
Monitor the static position of the head in space, necessary for the control of posture
Maculae and Static Equilibrium
107
Will also respond to linear acceleration forces, but not rotation
-Example: speeding up in a car on the road, traveling in a straight line
Maculae and Static Equilibrium
108
Contain supporting cells and hair cells
Maculae and Static Equilibrium
109
Each hair cell bundle has ___ stereocilia and a single ___ embedded in the ___ membrane
many sterocilia; single kinocilium; otholithic membrane
110
Gel-like mass studded with tiny CaCO3 stones called otoliths
otolithic membrane
111
tiny CaCO3 stones
otoliths
112
add weight to the gel membrane so that it shifts along the surface of
the hair cells with position changes
Otoliths
113
Dendrites of ___ nerve fibers encircle the base of the hair cells
vestibular
114
Macula in the utricle responds to ___ movement
horizontal
115
Macula in the saccule responds to ___ movement
vertical
116
Otolithic membrane movement which bends the hair cells (within a hair bundle) in the direction of the ___
kinocilium
| Activating the Macula
117
Hair cells trasduce signal which ___ vestibular nerve fibers
depolarizes
118
Thus, ___ the frequency of action potentials generated in the ___ nerves
increases; vestibular
119
Movement in the opposite direction (hair cells bend ___ from the kinocilium)
- Hyperpolarizes vestibular nerve fibers
- Reduces the rate of impulse propagation
away
120
From the increase/decrease in impulse frequency, the brain is informed of the changing position of the head
truth.
121
1. Nerve impulses generated in the ___ fiber
vestibular
122
2. When hairs bend toward the kinocilium, the hair cell depolarizes, exciting the nerve fiber, which generates ___ frequent action potentials.
more
123
3. When hairs bend away from the kinocilium, the hair cells hyperpolarizes, inhibiting the nerve fiber, and ___ the action potential frequency
decreasing
124
One ___ in the ampulla of each semicircular canal
Crista
125
Respond to rotational/angular movements
Crista Ampullares of Semicircular canals
126
Contain supporting cells and hair cells
Crista Ampullares of Semicircular canals
127
Each ___ has support cells and hair cells
crista
128
Each hair cell bundle has ___ stereocilia and a single ___ embedded in gel-like mass called CUPULA.
many
| Kinocilium
129
Dendrites of ___ nerve fibers encircle the base of the hair cells
Vestibular
130
Cristae respond to changes in _____ of the head
Velocity of rotatory movements
| Activating the Crista Ampullaris
131
When rotating/spinning, endolymph flows in the ___ direction of the spin
opposite
132
Reminder: each plane of rotation is represented by a
different semicircular canal
133
Endolymph flow over the cupula bends the embedded ___ in the cristae, Causes ___, and a ___ frequency of impulses
hairs
depolarization
high
134
Once the spinning stops, the ___changes direction over the cupula
- Hair cells bend in the opposite direction
- Causes ___ and ___ frequency of impulses
endolymph
hyperpolarization
lower
135
The result is that the brain is informed of ___ movements of the head
rotational
136
Equilibrium pathways are coplex and ___ traced
incompletely
137
Impulses travel directly to the reflex centers of the ___ in the brain stem and/or the ___
- both receive simultaneous inputs from the visual receptors and proprioceptors (eyes, muscles, and joints)
vestibular nuclei
| cerebellum
138
Fast input which permits a Fast reflexive response
- doesn't proceed to thalamus/cerebral cortex
- Permits our body to respond reflexively and quickly
Equilibrium Pathways
139
Reflex Output
| Extrinsic Eye Muslce Control for eye movement
Cranial Nerves
| III, IV, V
140
Reflex Output
| ___ nerve and ___ tract control for neck movements to change the position of the head in space
Accessory nerve
| Vestibulospinal tract
141
Labyrinth disorder that affects both the cochlea and the semicircular
canals, causing vertigo, nausea, and vomiting (and usually severe tinnitus)
Meniere's Syndrome
142
The rapid beating of the eyes following rapid & repeated rotatory movements
Nystagmus
143
Vestibular system interprets your head as “spinning” but your visual inputs show your
head has stopped spinning
Nystagmus
144
Benign Paroxysmal Positional Vertigo
BPPV
145
Loose otoliths enter the semicircular canal
BPPV (Benign Paroxysmal Positional Vertigo)
