Exam 2 Flashcards
What is the “normal” hearing range in children?
-10 to 15
What is the “Normal” hearing range in adults?
-10 to 25
What is the “slight” hearing loss range in children
16 to 25
The range for mild hearing loss
26 to 40
The range for moderate hearing loss
41 to 55
The range for moderately severe hearing loss
56 to 70
The range for severe hearing loss
71 to 90
The range for profound hearing loss
> 91
On an audiogram, this means it is conductive hearing loss
Normal bone conduction, impaired air conduction and a greater than 10dB difference
On an audiogram, this means it is sensory/neural hearing loss
Impaired bone conduction, impaired air conduction and less than or equal to 10 dB difference.
On an audiogram, this means it is mixed hearing loss
Impaired bone conduction, impaired air conduction and a greater than 10 dB difference.
Graphic representation of audiometric findings showing hearing thresholds as a function of frequency
Audiogram
Generally speaking, what is an audiogram testing?
How soft of an intensity at different frequencies can someone just be able to hear
List the information that an audiogram provides
- Degree of hearing loss
- Type of hearing loss
- Configuration of hearing loss
- Inter-aural symmetry
What is inter-aural symmetry?
How the ears compare to each other. Is the hearing loss the same or different in each ear? Is it bilateral?
To find degree of hearing loss you…
Put the earphones on and present various frequencies at various intensities and try and find the softest intensity at a certain frequency a person can hear.
The auditory nervous system is primarily a ____ system.
Afferent. Away from the Cochlea.
The auditory nervous system is _______. Meaning the right ear goes to the left cortex and the left ear goes to the right cortex.
Functionally crossed
(start of the auditory pathway)
_____ leave the _____ in an ______ and ______ at the _______
NEURONS leave the COCHLEA in an ORDERLY FASHION and then SYNAPSE at the LOWER BRAINSTEM
(also start of the auditory pathway)
_____ exit the _____ and then move ______ toward the ______
NERVE FIBERS exit the COCHLEA and then move CENTRALLY toward the MODIOLUS
This is where the cell bodies for the spiral ganglion
Modiolus
This is the central core of the Cochlea
Modiolus
After the cell bodies form the spiral ganglion, they then form _______
The cochlear branch of the auditory (VIII) nerve
Where are the nerve fibers from the apical turn of the cochlea located?
The middle of the bundle of the auditory nerve aka CN8
Where are the nerve fibers from the basal end of the cochlea located?
On the outside of the bundle of CN8 (The auditory nerve)
Why are the nerve fibers from the basal end and the apical end separated?
It keeps low frequency information together and High frequency information together
What is tonotopic arrangement?
The spatial representation of the frequency layout of the cochlea in retrocochlear structures
The auditory pathway goes from the ______ to the ______
Cochlea; auditory cortex
Nerve fibers from the cochlea pass through the ______
Internal Auditory Canal
Where does the internal auditory canal begin and terminate?
It begins at the cochlear modiolus and terminates at the base of the brain
The nerve fibers of the vestibular portion of the VIII cranial nerve are innervated by
the utricle, saccule, and semicircular canals
Other than CN8, what passes through the internal auditory canal?
The facial nerve and the internal auditory artery
How many cochlear neurons carry info to the brain?
30,000
After passing through the internal auditory canal, where does CN8 attach?
To the brainstem, at the cerebellopontine angle
This is where the cerebellum, medulla and pons are located
The cerebellopontine angle
CN8 attaches to the cerebellopontine angle, what happens here next?
The auditory and vestibular portions of VIIIth CN separate
One part of the cochlear bundle descends to the ______ and the other ascends to the ______
Dorsal cochlear nucleus; ventral cochlear nucleus
After separating from the vestibular portion of CN8, all nerve fibers move _____ into the ______
ipsilaterally; cochlear nucleus
Nerve fibers may pass from the _________ to the _______
Ventral Cochlear Nucleus; reticular formation
This is the center of the brainstem that communicates with just about all areas of the brain.
Considered a primary CNS control center
Reticular formation
From the cochlear nuclei, about ___ percent of nerve fibers ___ to the _____ side of the brain to the _____
75%; crossover; contralateral; Superior Olivari Complex
What is done in the Superior Olivary Complex?
Sound localization &
Control of the reflex muscles of the middle ear is regulated here (tensor tympani and stepedial muscles)
The point at which the crossover to the superior oliveri complex happens is called the…
Trapezoid body of the pons
From the superior oliveri complex, neurons proceed to…..
The lateral lemniscus
The lateral lemniscus is a major pathway for…
The transmission of impulses from the lower brainstem
This area receives ipsilateral and contralateral impulses from the lateral lemniscus as well as the superior oliveri complex
The inferior colliculus
The last subcortical relay station
The medial geniculate
After the medial geniculate, impulses ______ in ____ to the _____ in the ______
fan out; auditory radiations ;auditory complex; temporal lobe
CCSLIMA is
Cochlea, Cochlear nerve, Superior olivary complex, lateral lemniscus, inferior colliculus, medial geniculate, Auditory complex
Where is the primary auditory complex located? What is another name for the area?
Superior surface of the temporal lobe; Heschels gyrus
what kind of organization/ representation is seen in the primary auditory complex?
Tonotopic arrangement/ selective representation of frequency
Where does processing of speech information occur?
Throughout the central auditory system
Primary location for processing speech
left temporal lobe (for most)
white matter that connects the left and right hemispheres of the brain
Corpus callosum
The dominant ear for processing speech is ____. Why?
The right ear. The left temporal lobe is where speech is processed for most people. Speech information travels contralaterally from the right ear to the left temporal lobe. Information from the left ear has further to go since it will be sent to the right hemisphere then have to travel through the corpus callosum to the left.
Explain the efferent system
Parallels the afferent system but in reverse from the brain to the cochlea. Some end at the medial geniculate, some continue on to Inferior colliculate and the lateral lemniscus, Project ipsilaterally and contralaterally. Olivocochlear bundles come from the Superior olivary complex and run down the internal auditory canal and end at the inner and outer hair cells of the organ of corti
Processing in the auditory system occurs ___ and ____ the ____ and _____ tracts
up; down; afferent; efferent
Vestibular Schwannoma
Neoplasms Usually; unilateral;
Begins in IAC (internal auditory canal) and may grow out into cerebellopontine angle;
Very slow growing
Usually benign
What are two early signs of vestibular schwannoma?
Facial numbness
tinnitus with no hearing loss
What are 4 symptoms of vestibular schwannoma?
Facial numbness
Tinitus
HL
Vertigo
Name 5 tests for Vestibular schwannoma
PET scan CAT scan MRI Basic audiologic test battery ABR
What is the go to test for vestibular schwannoma?
ABR
What is ABR?
specialized objective test an audiologist would use to look at latency times of CNVIII and relay stations
What is used to treat smaller vestibular schwannomas? Larger?
Gamma knife, Cyber knife (3-5 treatments); surgery for larger
Inflammation of CNVIII
HL, some vertigo
Acoustic neuritis
Plaque swarm on nerves in your body and slow the transmission down
Can affect CNIII translation of stimuli
Multiple sclerosis
Normal outer hair cell function but absent CNVIII responses.
When otoacoustic emissions testing is done there are responses (otoacoustic emissions) but when hearing evaluation is done there is at least moderate HL.
Auditory neuropathy spectrum disorder
Bile deposits in the CNS and that includes the cochlear nuculi.
Product of the liver
Results in degeneration of the nerve cells coming in contact with that bile.
Kernicterus
Could cause damage to cochlear nuclei
Cerebra vascular accident (stroke)
Deprivation of oxygen and blood supply to the cochlear nuclei
Anoxia
Syndrome that is linked to learning disabilities
Mild hearing loss that occurs from chronic OM affects speech and language skills.
Minimal auditory deficiency syndrom
Explain Central Auditory Processing Disorder
Difficulty understanding speech when there is background noises present in the environment.
There is no hearing loss.
Not ADHD but could have ADHD along with CAPD
No intellectual difficulties or disabilities.
Delays in speech and language, learning to read, and spelling.
What are some risk factors of CAPD?
prematurity History of chronic OM CMV Metabolic disorders Family history Meningitis Lime disease
What are the 4 SCAN screening subtests?
Random Gap Detection
Filtered words
Auditory figure ground subtest
Competing word free recall
Scan subtests where there are 2 beeps very close together, ask if they hear 1 or 2. screens for timing/ processing disorders
Random Gap detection
monaural test of degraded speech with single syllable words
Filtered words
Monosyllabic words are presented within the background noise
Auditory figure ground subtest
A different word presented to each ear simultaneously, child instructed to repeat words in any order
Competing word free recall
How many sub-tests do they need to not pass in order to continue with test battery?
1
different word presented to each ear simultaneously; but child has to say one word first as directed “Repeat the word you hear in the right ear first then the left”
Competing words directed ear
2 sentences presented at same time to each ear, instructed to repeat only one sentence depending on which ear is being tested
Competing sentence test
60%-time compressed stimulus (20 sentences in the right ear and then 20 sentences in the left ear) then asked to repeat the sentence at a regular rate
Time compressed sentences
Recorded test with words repeated multiple times over 15 minutes and every time they hear ”dog” they raise their hand
Auditory continuous performance test
Dichotic with words in a sentence being alternated ear to ear “I (left ear) love (right ear) to (left ear) play (right ear) outside (left ear)”
Rapidly alternating speech perception
Patient has to respond with the duration descriptions, “long, short, long”, “short, short, long”, “long, short, short”
Duration pattern sequence
What are the 2 ways sound can be defined?
psychologically and physically
What is the psychological definition of sound?
An auditory experience
What is the physical definition of sound?
A series of disturbances of molecules within and propagated through an elastic medium (air, liquid, solid)
Sound is a ___ ____ transmitted by ___ ___ through a _____
Sound is a VIBRATORY ENERGY transmitted by PRESSURE WAVES through a MEDIUM
Hearing is the _____ of sound
perception
What happens when air molecules are set into motion?
They bounce off nearby molecules ten, because of their elasticity, return to their original resting place
What is it called when all molecules are pushed closely together?
Condensation (compression)
What is it called when all the molecules are spread out?
Rarefaction (spaces between condensation)
This is a graphic representation of compression and rarefaction graphed as a function of time
Sine Wave
A cycle is…
one complete compression and rarefaction
When a variety of frequencies are occurring together
Complex waves
What are complex waves?
When a variety of frequencies are occurring together
Sound can be characterized by….
its intensity and frequency
Related to the perception of loudness
Intensity
This is a unit of power
Bel
Relative unit of measure of intensity
Decibel (1/10 of a bel)
What are the 5 important aspects of decibel?
- calculation involves a ratio.
- uses a logarithm
- it is non-linear
- Several reference levels which must be specified
- It is a relative unit of measure
What is dB IL?
intensity level
What is dB SPL?
Sound pressure level; what we hear in everyday life
What is dB HL?
Hearing level
When is dB HL used?
Only used when you are talking about hearing evaluations with an audiometer.
The human ear is more sensitive to…
Speech Frequencies
Why does the audiometer have different intensities?
In the hopes of obtaining a person’s threshold
What is dB SL?
Sensation level
This is related to perception of pitch
Frequency
How is frequency measured?
of complete oscillations per unit of time (usually one second)
What 2 units are used to measure frequency?
cps or Hz
As wavelength ____ , frequency _____.
As wavelength decreases, frequency increases
As mass ______ , frequency _____.
As mass increases, frequency decreases.
What is considered low frequency in Hz?
below 1000 Hz
What is considered “middle of the road” frequency in Hz?
1000Hz
What is considered high frequency in Hz?
2000Hz and above
What frequency range is speech?
500-2000Hz
audiometer
An electronic instrument used to quantify hearing
What kind of tone does an audiometer produce?
Pure tone
What are the two types of audiometers?
Diagnostic and Screening
This type of audiometer can deliver speech signals either recorded or via microphone?
Diagnostic Audiometer
This audiometer can produce masking
Diagnostic audiometer
What are the 3 main components of audiometers?
Oscillator, Attenuator, and interrupter switch
This generates pure tones at specific frequencies in audiometers
Oscillator
This controls the intensity level of the signal in audiometers
Attenuator
This is what presents and controls the duration of a signal in audiometers
Interrupter Switch
Name 3 transducers
Insert earphones, supra-aural earphones, and bone oscillator
What is a sound level meter?
An electronic instrument used to measure environmental sound intensity
Why would a client require a sound level meter in therapy?
To monitor the intensity of their voice
Describe a sound treated room
Free standing units that have no contact with room walls, ceiling and floor. It is not sound proof.
What are the types of hearing loss?
Conductive, Sensory/Neural, and mixed.
This type of test assumes examiner’s hearing is normal and does not provide numerical data
Tuning fork tests
This tuning fork test compares tester’s hearing to the patient’s hearing
Schwabach test
This tuning fork test compares the patient’s hearing by air conduction to bone conduction
Rinne Test
This tuning fork test is based on the occlusion effect
Bing Test
This tuning fork test is a test of lateralization
Weber test
What is a biologic test?
When you put the earphones on yourself to make sure they are working before putting them on the client
What are considered false negative/ positive responses?
Raising hand without hearing sound/ hearing sound without raising hand. Trying to fake it.
During testing, what should you consider for the clients reaction time?
Cognition
On headphones, what color represents the right ear?
Red
On headphones, what color represents the left ear?
Blue
When should testing instructions be given?
Prior to earphone placement
During testing, should hearing aids be removed?
yes
During the testing procedure, what are 2 things you should do before you begin?
Get a case history, Do an otoscopic examination
Lowest dB level at which the patient is able to perceive the tone 50% of the time it is presented
Threshold
What ear should you start with during testing?
The better ear. If unknown, start with the right ear.
What Hz and dB should you begin testing at?
1000Hz with 30dB
If there is no response at 1000Hz with 30dB what do you do?
Increase by 10dB
If there is a response at 1000Hz with 30dB what do you do?
Decrease by 10dB
If there was a response at 1000Hz with 30dB and you then decreased by 10dB but there was no response what do you do?
increase by 5dB
During testing, how long should you continue the “bracketing procedure”?
Until you have a response at the same dB 2 out of 3 tries
This is an example of threshold testing
Present 1000Hz to Right ear at 30dB, response, decrease by 10*
Present at 20dB, no response, increase by 5
Present at 25dB, no response, increase by 5
Present at 30dB, response, decrease by 10**
Present at 20dB, no response, increase by 5
Present at 25dB, no response, increase by 5
Present at 30dB, response***
30dB is threshold at 1000Hz, Right ear
What symbol represents right ear air conduction on an audiogram?
O
What symbol represents left ear air conduction on an audiogram?
X
Define audiogram
A graphic representation of audiometric findings showing hearing thresholds as a function of frequency
I a pure tone easier to hear as a pulse or at a steady state?
A pulse
What is SRT?
Speech recognition threshold
What is PTA?
Pure tone average
How do you calculate PTA?
500, 1000, and 2000Hz averaged
What is calculating PTA useful?
It is useful for predicting SRT
This is determined by Air conduction thresholds
Degree of hearing loss
This part of testing can describe the entire auditory system (outer, middle and inner ears)
Thresholds by Air conduction
What is air conduction testing?
Signal is presented through the air via the earphones
This is determined by bone conduction testing
type of hearing loss
What is the occlusion effect?
Enhancement of low frequency sound when the ear is covered
Where is a bone oscillator placed?
Mastoid or forehead. Cannot be touching pinna.
Is the activation of the cochleas separate or simultaneous during bone conduction testing?
When you stimulate the skull via bone conduction, both cochleas are activated simultaneously
This type of conduction has acoustic separation
Air conduction
This type of conduction lacks acoustic separation
Bone conduction
What 3 ways does hearing by bone conduction occur? Are they happening all at once or just one at a time?
- Inertial BC
- Distortional BC
- Osseotympanic BC
All 3 happen not just 1
When the bones of the skull vibrate/move and they cause air in the EAC to vibrate. Some of those sound waves/ vibrations will move out of the EAC and some will move down the EAC and hit the TM.
What type of bone conduction is this?
Osseotympanic BC
When the bones of the skull become distorted as the bones of the skull are vibrating and this causes the inner ear structures to become distorted in the same way as they are stimulated via air conducted sounds.
What type of bone conduction is this?
Distortional BC
When the ossicular chain, owing to its inertia, lags behind so that the stapes moves in and out of the oval window into the cochlea.
What type of bone conduction is this?
Inertial BC
Describe conductive hearing loss
outer and middle issues: ex. too much wax, otosclerosis, otitis media, canal atresia; usually medically treatable
Describe sensory neural hearing loss
Inner ear and beyond; outer hair cells, inner hair cells, leak in fluid, nerve damage.
Usually not medically treatable.
Name 3 types of ear phones
supra aural, circum aural, and insert
how often does a diagnostic audiometer require calibration?
annually
Describe infection control procedures for a test environment
wipe off everything with an appropriate disinfectant. Not alcohol because it will dry out cushions
There is a fan/vent to circulate air
Disposable tips- one set per person
How does bone conduction testing work?
it stimulates the cochlea by bypassing the outer and middle ear
What does an audiometer do?
Produces Pure tones, attenuates (vary the level of intensity) them, delivers them to various transducers
Consistent so you can actually quantify a persons hearing
