Med Neuro Auditory

Front 1

What is conductive hearing loss?

Back 1

A problem with mechanical transmission via the outer ear or middle ear structures.

Front 2

What is sensorineural hearing loss?

Back 2

1. mechanoelectrical transduction of sound via the fluid of the
cochlea to the hair cells (sensory )

2. transmission of neural signals in the auditory neural pathways (neural )

3. processing of auditory information in auditory cortex (cortical)

Front 3

What are the 3 kinds of sensorineural hearing loss?

Back 3

sensory, neural, cortical

Front 4

What frequency of tuning fork is the best for a tuning fork test?

Back 4

512 Hz

Front 5

What principles are tuning fork tests based on?

Back 5

Sound travels better through bone than air (with no assistance from ossicles or tympanic membrane)

With conductive hearing loss, bone-transmitted sounds are actually louder (this is the occlusion effect)

Front 6

Describe the Weber test

What are 3 possible outcomes?

Back 6

Tuning fork on cranium (midline)

1. No loss, should be bilaterally equal

2. Conductive loss, should be louder in affected ear

3. Sensorineural loss, should be louder in opposite ear

Front 7

Describe the Rinne test.

Back 7

The Rinne test is performed by placing a vibrating tuning fork initially on the mastoid process until sound is no longer heard, the fork is then immediately placed just outside the ear. Normally, the sound is audible at the ear.

Air conduction uses the apparatus of the ear (pinna, eardrum and ossicles) to amplify and direct the sound whereas bone conduction bypasses some or all of these and allows the sound to be transmitted directly to the inner ear albeit at a reduced volume, or via the bones of the skull to the opposite ear.

In a normal ear, air conduction (AC) is better than bone conduction (BC)

AC > BC, and this is called a positive Rinne.

In conductive hearing loss, bone conduction is better than air

BC > AC, a negative Rinne.

Note + and - are different.

Front 8

What is an audiogram?

Back 8

A behavioral test of hearing.

Front 9

Name a behavioral test of hearing

Back 9

Audiogram.

Front 10

What are 3 parts of an audiogram?

Back 10

1. Pure tone thresholds
a. 250, 500, 1000, 2000, 4000, 8000 Hertz

2. Speech reception thresholds
---spondee word list (two syllables, equal stress)

3. Word (speech) recognition test
--phonetically balanced word list
--percent correct

Front 11

What is Impedence Imittance Audiometry?

Back 11

Tympanogram: calculates compliance changes against changes in air
pressure

Tests for middle ear fluid/otitis media, perforated TM,
ossicular fixation, ossicular disarticulation.

2. Acoustic reflex test/stapedial reflex test

Front 12

What is an auditory brain stem response? (ABR, BAER)

Back 12

Measures small electrical potentials generated in the cochlea, auditory
nerve (CN VIII), and brain stem auditory nuclei in response to sounds

Front 13

What are otoacoustic emissions and when are they important?

Back 13

The ear literally emits sounds. They are thought to arise from the outer hair cells of the cochlea, based on
their electromotility properties.

Can be spontaneous or in response to stimulus.

Infancy.

Front 14

What is a cholesteatoma?

Back 14

A cholesteatoma is a benign growth of skin in an abnormal location such as the middle ear

Front 15

What are some diseases of the middle ear?

Back 15

tympanic perforation
otitis media
cholesteatoma
ossicular fixation
ossicular disarticulation

Front 16

What are some diseases of the external ear/skin?

Back 16

cerumen impaction
otitis externa
foreign bodies
ear canal
stenosis
exostosis
osteoma


Skin:
actinic damage
basal cell carcinoma
squamous cell carcinoma
dermatitis

Front 17

What is an osteoma?

Back 17

An osteoma (plural: "osteomata") is a new piece of bone usually growing on another piece of bone, typically the skull. It is a benign tumor.

Front 18

What is an exostosis?

Back 18

An exostosis (plural: exostoses) is the formation of new bone on the surface of a bone.

Front 19

What is cerumen impaction?

Back 19

ear fucking wax.

Front 20

What are some diseases of the inner ear?

Back 20

Cochlea--
sensorineural hearing loss
Meniere's disease
congenital abnormalities

labyrinth--
vertigo
labyrinthitis

Front 21

What are symptoms of Meniere's disease?

Back 21

spinning, deafness, ringing.

The symptoms of Ménière’s disease are episodic rotational vertigo (attacks of a spinning sensation), hearing loss, tinnitus (a roaring, buzzing, or ringing sound in the ear), and a sensation of fullness in the affected ear.

Front 22

What are some bone-related ear diseases?

Back 22

mastoid--
mastoiditis
cholesteatoma

Front 23

Which of the following is NOT true of the acoustic middle ear reflex?
a. It tends to prevent damage due to overstimulation.
b. It increases the dynamic range of hearing.
c. It reduces masking of higher frequencies by low frequency sounds.
d. It would be activated by a 60 dB SPL sound.
e. ALL of the above are true of the acoustic middle ear reflex.

Back 23

d. It would be activated by a 60 dB SPL sound.

Front 24

Which of the following is NOT true of the place code concept of sound
frequency analysis?
a. Higher frequency sounds are transduced by hair cells nearer to the stapes end of the cochlea.
b. Lower frequency sounds are transduced by hair cells nearer to the helicotrema end of the cochlea.
c. Hair cells respond to specific frequencies of sound in part because of local
resonance properties of the basilar membrane.
d. Active changes in the length of the outer hair cells can modulate the local resonance of the basilar membrane.
e. ALL of the above statements are correct

Back 24

e. ALL of the above statements are correct

Front 25

The myelinated portion of a mechanoreceptive neuron is similar in function to:
a. Outer hair cells
b. Inner hair cells
c. Tectorial membrane
d. spiral ganglion cells
e. stereocilia

Back 25

d. spiral ganglion cells

Front 26

A low frequency sound will:
a. depolarize hair cells at the apex of the cochlea
b. hyperpolarize hair cells at the apex of the cochlea
c. depolarize hair cells at the base of the cochlea
d. hyperpolarize hair cells at the base of the cochlea
e. a combination of two of the above choices

Back 26

e. a combination of two of the above choices

Front 27

A lesion of the lateral superior olive would result in:
a. an inability to hear high frequency sounds
b. an inability to hear low frequency sounds
c. an inability to localize some sounds
d. disabled speech discrimination
e. Complete deafness in the contralateral ear

Back 27

c. an inability to localize some sounds

Front 28

Which of the following structures in the cochlea contains the hair cells?
a. tympanic membrane
b. scala media
c. organ of Corti
d. stria vascularis
e. basilar membrane

Back 28

c. organ of Corti

Front 29

All of the following statements are true EXCEPT:
a. The vibration of the round window releases energy from the cochlea.
b. Waves of vibration travel from the stapes toward the helicotrema.
c. High frequencies produce peaks of vibration near the oval window.
d. Hair cells near the oval window are most sensitive to low frequencies.
e. All of the above are correct.

Back 29

d. Hair cells near the oval window are most sensitive to low frequencies.

Front 30

The following structures are part of the central auditory pathways except:
a. Medial superior olive
b. medial geniculate nucleus
c. inferior colliculus
d. ventral cochlear nucleus
e. All are parts of the auditory pathways

Back 30

e. All are parts of the auditory pathways

Front 31

About how many decibels SPL (i.e., dB re 20 μPa = dB re 0.0002 dynes/sq cm) would a household vacuum cleaner produce when measured from a distance of 5 feet?
a. 10 to 20
b. 140 to 150
c. 30 to 40
d. 70 to 80
e. 120 to 130

Back 31

d. 70 to 80

Front 32

What is the most common cause of hearing deficits in the U.S.?
a. Rupture of the tympanic membrane
b. Lesions of the auditory cortex resulting from stroke
c. Loss of hair cells
d. Aminoglycoside antibiotics
e. None of the above

Back 32

c. Loss of hair cells

Front 33

Why is the middle ear force transformation system necessary?
a. It encodes the different frequencies
b. To compensate for differences in density and elasticity between air and the fluid in the inner ear
c. To funnel sound waves towards the tympanic membrane
d. It prevents skin divers from damaging the delicate inner ear
e. None of the above

Back 33

b. To compensate for differences in density and elasticity between air and the fluid in the inner ear

Front 34

Otosclerosis:

What?
Symptoms?
Treatment?

Back 34

Hereditary disorder of otic capsule bone; Abnormal bone formation usually adjacent to the oval window, causing fixation of the footplate of the stapes

Gradually progressive conductive hearing loss, as much as 40-50 decibels (dB)

Can be successfully treated by stapedectomy/stapedotomy --replacement of
the stapes with a prosthesis

Front 35

What is Aural Atresia?

Back 35

Congenital absence of the ear canal

Front 36

Acoustic Trauma

What?
Treatment?

Back 36

Brief exposure to high intensity noise can result in permanent hearing loss. Prolonged exposure to medium-high intensity noise (> 90 dB) may result in
permanent hearing loss. Noise damages the cochlea, mainly the outer hair cells

No known treatment, prevention is key

Front 37

What is Presbycusis?

Back 37

Degeneration of hair cells and/or cochlear nerve neurons

Hearing loss especially at high frequencies

Front 38

What medications can be ototoxic?

Back 38

aminoglycoside antibiotics
furosemide (Lasix) I.V.
cisplatin
vancomycin
quinine, chloroquine, antimalarials
6. salicylates

Front 39

What is GLOMUS TYMPANICUM? GLOMUS JUGULARE?

Back 39

Paragangliomas arise from the glomus cells.

Front 40

Most hearing deficits arise as the result of damage within

Back 40

the cochlea

Front 41

What percentage of cochlear hearing loss stems from hair cell loss?

Back 41

80%

Front 42

What are anatomical hallmarks of the auditory pathways?

Back 42

Decussations, bilateral projections

Front 43

What preserves auditory function in most cases of CNS lesions?

Back 43

bilateral redundancy of information transmission

Front 44

Are specific deficits of hearing are useful for neurological diagnosis?

Why?

Back 44

No. bilateral redundancy of information transmission.

Front 45

What is presbycusis?

Back 45

Age-related deafness

Front 46

How fast does sound travel (in air)?

Back 46

340 m/sec

Front 47

What sound perception determines pitch?

Back 47

Frequency

Front 48

What sound perception does frequency determine ?

Back 48

Pitch

Front 49

Vowels are _________

Back 49

tonal

Front 50

consonants are ________

Back 50

noisy

Front 51

Clicks contain many frequencies (T/F)?

Back 51

T

Front 52

Clicks contain one frequency (T/F)?

Back 52

F

Front 53

What contain transitions, stops and clicks?

Back 53

consonants

Front 54

What three features do consonants have?

Back 54

transitions, stops, clicks.

Front 55

What carries much of the information content of speech?

Back 55

The high frequencies associated with consonants

Front 56

What frequencies "go" first in hearing loss?

Back 56

High

Front 57

When patients have high frequency hearing loss, what is a typical complaint?

Back 57

Patients who experience this often say they can hear, but they complain of reduced ability to understand speech.

Front 58

What is a typical young adult normal hearing range?

Back 58

20 Hz to 20,000 Hz (20 kHz)

Front 59

What is a typical older adult normal hearing range?

Back 59

20 Hz to 16,000 Hz (16 kHz)

Front 60

Sensitivity between ____ to ____ Hz is critical for understanding speech.

Back 60

200 to 6000 Hz

Front 61

We perceive sound pressure increases as increases in ______

Back 61

loudness

Front 62

What is sound pressure at the just detectable level called?

Back 62

The auditory threshold

Front 63

What is static atmosphere pressure?

Back 63

over 1000000 dynes/sq cm

Front 64

What is the dynamic range of hearing defined as?

Back 64

the span of sound magnitudes from the weakest to the strongest sounds throughout a range where *differences* in loudness can be detected by our auditory system.

Front 65

How much greater is 120 dB than 0 dB?

Back 65

1,000,000 times

Front 66

Middle ear ossicles are called:

Back 66

Malleus, incus, stapes

Front 67

What is the function of the middle ear?

Back 67

Transform air pressure to fluid pressure

The middle ear transforms acoustic variations in air pressure into vibrational displacements that can pass into the cochlear fluids at the oval window.

Front 68

What is the function of the eustachian tubes?

Back 68

The Eustachian tube allows equalization of static pressure differences across the tympanum.

(When the Eustachian tube opens that nulls out any *static* difference between the pressure inside the middle ear and the outside atmospheric pressure).

Front 69

The acoustic middle ear reflex _____________ to the cochlea for sounds _______ or ______

Back 69

reduces sound transmission

75 dB SPL or greater.

Front 70

What 2 nerves are necessary for the acoustic middle ear reflex?

Back 70

Trigeminal nerve > Tensor tympani > Malleus
Facial nerve > Stapedius > Stapes

Front 71

What 3 things does the middle ear reflex do?

Back 71

1. prevents damage due to overstimulation.

2. increases the dynamic range of hearing, by reducing middle ear efficiency in transmitting sound energy in the 75 dB to 120 dB SPL range .

3. reduces masking of high frequencies by low frequency sounds. (Functions 2 & 3 are thought to be important for speech discrimination in noisy environments.)

Front 72

Perilymph is high ___ and low ____

Back 72

Na, K

Front 73

Endolymph is high ___ and low ____

Back 73

K, Na

Front 74

What is the electrical potential in the scala media?

Back 74

+80 mV

Front 75

High frequency sounds travel the whole length of the cochlea (T/F)?

Back 75

F. They die out.

Front 76

How many hair cells in the cochlea?

Back 76

16,000

Front 77

What is the tectorial membrane's composition?

Back 77

Acellular secreted protein

Front 78

What makes up the organ of corti?

Back 78

Tectorial membrane, hair cells, supporting cells, nerve terminals

Front 79

What are Microphonic potentials?

Back 79

They arise from *summed* receptor potentials of hair cells

Front 80

Are afferent chemical synapses that transmit signals from the hair cells to nerve terminals phasic or tonic?

Back 80

tonic

Front 81

Where are the cell bodies of the afferent auditory neurons?

Back 81

The spiral ganglion

Front 82

A spiral ganglion neuron contacts how many inner hair cells?

Back 82

One

Front 83

How many neurons may contact an inner hair cell?

Back 83

many

Front 84

A spiral ganglion neuron contacts how many inner hair cells?

Back 84

many

Front 85

the cochlea's place code is said to be an example of _________

Back 85

labeled line coding

Front 86

What anatomical arrangement is critical for understanding speech?

Back 86

The precise registry between a single-file line of inner hair cells along the basilar membrane and the afferent neurons

Front 87

Where do all the spiral ganglion neurons terminate?

Back 87

in the DL brainstem within the VCN and DCN.

Ventral Cochlear Nucleus (VCN) and Dorsal Cochlear Nucleus (DCN).

Front 88

“Tonotopic” spatially ordered frequency representations are maintained throughout _____________ levels in the central auditory system.

Back 88

many but not all

Front 89

Decussations and bilateral projections occur starting with _________

Back 89

the axons that arise from neurons in the cochlear nuclei, the second order neurons in the auditory pathway.

Front 90

What is the basic auditory pathway?

Back 90

Cockle Olive Lemon Biscuit Colliculus Geniculate

Cochlear <b>nuclei</b> (R medulla)

Superior olive (M pons)

Nucleus of Lateral Leminiscus (Pons/Midbr)

Inferior colliculus (Caud Midbrain)

Medial Geniculate (Rost Midbrain)

Primary Auditory cortex

Front 91

What are ITD and IID?

Back 91

Interaural time detection, interaural intensity detection

Front 92

What occurs in the medial superior olive?

Back 92

Interaural Time Detection (ITD)

Front 93

Interaural delay time detection occurs in the

Back 93

The medial superior olive

Front 94

The neurons in the ____________ project bilaterally to the Medial superior olives.

Back 94

Anteroventral Cochlear Nucleus (AVCN)

Front 95

The neurons in the Anteroventral Cochlear nucleus project bilaterally to the _________

Back 95

medial superior olives.