exam 1 Flashcards

1
Q

prevalence of hearing loss

A
  • increases with age
  • hearing loss over 65 = 13 million
  • 35 million americans with hearing loss
  • 6/1000 born with hearing loss
  • 90% of children have at least 1 ear infection by age 6
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2
Q

impact of hearing loss

A
  • financial burden priceless
  • affects general health, psychosocial well being, and generated income
  • 30% cant afford treatment
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3
Q

evolution of audiology

A
  • began after WWII
  • otology + SLP = aural rehab
  • 1945 dr. raymond carhart
  • grant fairbanks - u of i
  • 1988 set gaols for doctorate level via academy of dispensing
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4
Q

why is audiology important in SLP

A
  • hearing loss has a direct impact on speech and languare

- many communicative disorders involve hearing complicaitions

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5
Q

roles of audiologits:

specialties

A
  • medical audiology
  • educational audiology
  • pediatric audiology
  • dispensing/rehab audiology
  • industrial audiology
  • recreational audiology
  • animal audiology
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6
Q

roles of audiologists:

employment settings

A
  • hospitals
  • physicians office
  • private practice
  • other
  • schools
  • college/university
  • speech and hearing center
  • home care
  • industrial
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7
Q

roles of audiologists:

professional societies and organizations

A
  • AHSA - set standards for practice of audiology and accreditation for academic programs
  • asha - CCC - certificate of clinical competance

-AAA - american academy of audiology - increased public awareness of hearing and balance disorders and well as work with gov. on national level

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8
Q

roles of audiologists:

professional roles with in the scope of practice for audiologists

A

-set and receive practice standards, protocols and guidelines for the practice of audiology to ensure quality patient care. ASHA needs a CCC. AAA requires fellowsing (FAAA)

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9
Q

outer ear landmarks

A
  • canal
  • TM
  • pinna
  • meatus
  • external auditory canal
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10
Q

Tympanic membrane landmarks

A
  • umbo (point and center of TM at which it is most retracted)
  • pars flaccida - loose folds of tissue above malleus
  • pars tensa - remaining tissue portion of TM
  • meniscus line - edge of ear drum
  • manubrium of malleus
  • long crus of incus
  • cone of reflected light
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11
Q

middle ear

A
  • malleus, incus, stapes

- mastoid process

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12
Q

inner ear

A

-cochlea, which serve to convert waves into a message that travels to the brain stem via the auditory nerve

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13
Q

auditory nerve

A

VIII cranial nerve which comprises auditory and vestibular branches passing from inner ear to brainstem

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14
Q

air conduction pathway

A
  • transmission through outer ear, middle ear, and inner ear and higher up
  • AC loss can occur in ME or outer ear
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15
Q

insert ear headphones

A
  • cleanlier

- foam goes into the ear, increase inter-aural attenuation by around 80 dB

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16
Q

supra-aural

A
  • transducer
  • AC receiver
  • rubber cushion fits over the ear
  • increase iner-aural attenuation by 40 dB
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17
Q

inter-aural attenuation

A

IA
-loss of energy in a sound in either AC or BC as it travels from test ear to nontest ear

*number of decibels lost in cross-hearing

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18
Q

headphone placement and sound delivery

A
  • ear canal should be checked for blockage or collapse
  • earphones placed with grid directly across ear canal with hair/glasses out of the way
  • test 250 - 8000 Hz
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19
Q

decibels

A

a unit for expressing the ratio between two sound pressures or two sound powers

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20
Q

cross hearing

A

the reception of a sound signal during a hearing test by either AC or BC in the NTE

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21
Q

bone conduction pathway

A
  • transmission that stimulates IE directly through mechanical vibration of the skull
  • BC impairment can occur in the IE or auditory nerve
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22
Q

bone vibrator placement and sound delivery

A
  • cannot touch pinna or hair
  • test ear never covered if using masking
  • test 250 - 4000 Hz
  • **must use masking if ABG is more than 10 dB
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23
Q

air bone gap

A

-the amount by which the air-conduction threshold of a patient exceeds the bone conduction threshold at any given frequency in the same ear

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24
Q

modes of vibration:

distortional

A
  • leads to the distortion of the cochlea
  • moves fluid and generates perception of a tone
  • inner ear mainly
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25
modes of vibration: | inertial
-middle earbones set into vibration and ligaments and tendons set ossicles into motion and movement will lag in and out of stimulation of the cochlea
26
modes of vibration: | osseo-tympanic
- air in ear-canal into vibration and then ear drum into motion, then ossicles then fluids - primarily outer ear
27
advantages/disadvantages of BC testing from forehead
- more comfortable | - but gives a lower threshold by 10dB
28
advantages/disadvantages of BC testing from mastoid
- more reliable | - but possible cross-hearing
29
conductive portion of auditory system
- sound attenuation (a decrease in strength of a sound) is the result of a conductive hearing loss - impaired air conduction with normal bone conduction
30
sensorineural portion of auditory system
-same amount of attenuation for both AC and BC but the main issue is in the IE
31
what info comes from BC that we cant get from AC
-info about if the IE and AN are correctly functioning
32
conductive hearing loss
- impairment of the outer ear or ME or AC testing | - normal BC testing, normal IE and AN function
33
attenuation
decrease in the strength of a sound
34
sensorineural hearing loss
- impairment in the IE or AN - AC and BC EQUALLY impaired - ABG < 10dB
35
mixed hearing loss
- impairment to the ME or IE - results in loss of BC but even greater loss of AC - ABG
36
bing test
- to determine the presence of the occlusion effect by examining AC and BC - with SNHL and normal hearing there will be a positive bing - for conductive hearing there will be no change or a negative bing - place fork on mastoid and open and close tragus to occlude
37
rinne test
- compare hearing sensitivity of BC to AC - rinne positive = normal hearing sensitivity as well as SNHL will hear tone longer with AC - rinne negative = patients with conductive hearing loss will hear BC - false rinne = response indicates negative when the dysfunction is in other ear * opposite ear (better cochlea is responding) * have to mask b/c of cross-hearing
38
schwabach test
- test BC and compare to examiners results - place on mastoid and keep track of how long patient hears sound until it is inaudible - normal results - can still suggest conductive hearing loss - diminished - patient stopped before tester suggests SNHL - prolonged - suggests conductive
39
weber test
- place fork in center of the forehead to determine which ear has the better cochlea - tone will lateralize to the better cochlea - UNHL - patient hears tone in poorer ear indicative conductive hearing loss - SNHL - patient hears tone in better ear b/c this cochlea is more sensitive - test used when assumption that hearing loss is present and asymmetrical
40
lateralization
-sound introduced directly to the ears is head in the right ear, left ear, or the midline if hearing is symmetrical
41
occlusion effect
-impression of increased loudness of a bone conducted tone when the outer ear is tightly covered (occluded)
42
problems and limitations of tuning fork tests
- provide only qualitative data | - only able to show that there is a loss not how much
43
stenger principle
when 2 tones are of the same frequency and presented to both ears simultaneously and only the louder one is perceived (weber)
44
brownian motion
-the constant random colliding movement of molecules in a medium with compression and rarefaction
45
complex sound
sounds composed of 2 or more tones that have a repeating or periodic time waveform (complex tone: more than 1 pure tone signal)
46
condensation and rarefaction: the difference
- condensation is the portion of sound wave where the molecules of the medium are compressed together and a decrease in pressure occurs - rarafaction is that portion of sound wave where the molecules become less densely packed per unit of space
47
transverse vs. longitudinal
- longitudinal is a wave in which the particles of the medium move along the same axis as the wave - transverse wave is a wave in which the motion of the molecules of the medium is perpendicular to the direction of the wave
48
sine waves
-waveform of pure tone showing simple harmonic motion
49
pure tones
-seen by oscillations of cycles, pure tones are the tones of only one frequency (no harmonics)
50
periodic vs aperiodic sound waves
- periodic repeats over time | - aperiodic varies randomly over time and doesnt have a fundamental frequency
51
oscillation
the back and forth movements of a vibrating body
52
spectrum
the sum of the components of a complex wave
53
vibration
the to and fro movement of a mass - in a free vibration the mass is displaced from its position of rest and allowed to oscillate without outside influence - in forced vibration the mass is moved back and forth by applying an external force
54
frequency
cycles per second
55
period
time to complete one cycle
56
physical effects of mass length and stiffness on frequency
-shorter length = higher frequency and lower mass | higher frequency, higher stiffness = higher frequency
57
amplitude
the extent of the vibratory movement of a mass from its position of rest to that point farthest from the position of rest - magnitude of vibration of air particles - distance of mass after force is applied
58
intensity
the amount of sound energy per unit of area | *proportional to pressure squared
59
pressure
force per unit area | -pascals Pa
60
phase
the relationship between 2 or more waves - in-phase - 2 sinusoids are said to be in phase when the difference in phase degrees between 2 identical time points equals zero - out phase - same frequency with different starting phases
61
wavelength
AMOUNT sound travels in 1 period or cycle | -as freq increase wavelength decreases
62
fournier analysis
the mathematical breakdown of any complex wave into its component parts consisting of simple sinusoids of different frequencies
63
fournier synthesis
rebuilding those complex sounds
64
fundamental frequency
the lowest frequency of vibration in a complex wave
65
ANSI
american national standards institute - organization established to oversee the creation and use of guidelines that impact all centers of US business - these include acoustical devices like audiometers, construction equipment and more - also involved in accreditation of a variety of programs
66
ISO
- international organization for standardization | - world wide consortium of 148 nations who oversee and set guidelines for 1000s of devices including audiometers
67
equipment used to calibrate audiometer and transducers
- pure tone oscillator and noise generator - frequency switch and spectrum swtich - signal/input selector, tone switch, attenuator and outputs selector - transducers: supra-aural earphones and insert earphones, speakers, etc
68
ambient noise and its effect on calibration and hearing sensitivity
ambient noise is noise from the environment and it can alter calibration and hearing sensitivity
69
biological check
- informal but careful evaluation of operational status of the audiometer - carried out through direct observation and completed daily before used - examine headphones, listen for static or clicks - set attenuator to high intensity and listen for hum - move attenuator in 5 dB increments for steady linear increase in loudness - listen for cross-talk between headphones - check BC vibrator cord - listen for live-voice and tape recordings for quality of speech
70
axes
- y axis is hearing level in dB | - x axis is frequency in Hz
71
frequency
- pitch - Hz - typical range is 20 - 20,000 Hz
72
intensity
- loudness | - dB
73
what can we record on an audiogram
- degree type - symmetry - lateralization - masking - speech audiometry - tympanometry
74
normal hearing
-10 - 25 dB
75
mild
26-40 dB
76
moderate
41-55 dB
77
moderately severe
56-70 dB
78
severe
71-90 dB
79
profound
91-120 dB
80
threshold
the level of a pure tone or complex signal at which it can be detected 50% of the time by a listener
81
db HL
hearing level - standard reference used for measuring hearing threshold levels - 0 dB HL reflects a different SPL depending on the frequency
82
dB SL
sensation level - used to specify intensity of stimuli presented to a given patient relative to a patients threshold - used to describe presentation level of other audiometric tests
83
dB IL
intensity level
84
dB SPL
sound pressure level
85
dB RETSPL
- reference equivalent threshold SPL | - formal hearing sensitivity based on an absolute physical measurement
86
audiometric zero
average for normal hearing thresholds
87
dB RETFL
reference equivalent threshold force level
88
threshold audibility/ minimum audibility curve
-lowest you can hear and threshold is highest
89
difference between absolute and differential sensitivity
- absolute is the ability to detect a faint sound | - differential is the ability to detect differences or changes in intensity, frequency, or other dimensions of sounds
90
parts of the audiometer
- power switch - frequency selector - attenuator (determines amplitude or intensity of test signal being presented) - signal selector - output selector (AC or BC) - earphone or loudspeaker selection - tone interruptor (presentation bar that presents the test signal)
91
AC and BC ranges
AC - 125 - 8000 Hz | BC - 250 - 4000 Hz
92
basic audiologic exam
- otoscopy - screening - history - speech - AC/BC testing - tympanometry
93
what info is obtained in test history
- review of symptoms - family history - noise exposure history - medical history - communication difficulties or needs
94
how is info for an adult different than a child
-childrens can impact communication and speech development whereas adults are being evaluated later on in life suggesting noise exposure, old age etc
95
what to look for during otoscopy
- earwax - foregin objects - physical abnormalities - infections - tumors - polyps - TM and outer ear canal
96
why is otoscopy performed
-looks for any blockage or abnormalities that could affect threshold results
97
why is infection control important
-infections impact hearing and hearing sensitivity which can also impact communication and speech
98
purpose of threshold testing
- to determine hearing sensitivity | - specific to determine HOW much hearing is lost
99
target populations for hearing screenings
- newborns - children entering school - adults in occupations with potentially dangerous levels of noise
100
describe hearing screening
- large number of people rapidly being screened - find out who is at risk - select few frequencies - select fixed cutoff level
101
hearing screening failure
ASHA says that failure at ANY frequency in either ear means FAIL and rescreen to see if results are due to lack of attentiveness -if failure after second screening refer for comprehensive assessment
102
factors that may influence measures of sensitivity
- calibration - listening check - test environment - patient seating
103
uses and limitations of pure tone threshold testing
- limitations - does not predict communication competence - same audiograms can have different HL - uses - test hearing - type of loss, degree, and configuration
104
pure tone threshold procedure
- start at 1000 Hz, 30 dBHL - if no response raise to 50 dBHL and continue to raise by 10 dB until response is obtained - when response is obtained the level lowered in 10 dB steps until no response - then raise by 5 dB until response - then lower in 10 dB steps
105
types of patient response
- positive - negative - false positive: responding to when audiometer dials are being changed or responding to an internal sound like tinnitus - false negative: failure to indicate they heard tone when tone is audible
106
critical criterion for pure tone threshold procedure
-lowest level at which patient responds 50% of the time in a series of ascending trials with a minimum of 3 responses at a single level
107
what is masking
-the process by which the threshold of a sound is elevated by the simultaneous introduction of another sound
108
ANSI definition of masking
-the process byt which the threshold of hearing for one sound is raised by the presence of another sound and the amount by which the threshold of hearing for one sound id raised by the presence of another sound expressed in decibels
109
critical band concept
- critical band is a portion of continuous band of sound surrounding a pure tone - when the sound pressure level of this narrow band is the same as the sound pressure level of the tone, the tone is barely perceptible - uses minimum sound pressure * best masking for least SPL - contralateral, direct, ideal * **narrowband best for masking
110
cross hearing
- signal delivered to test bar presented at large enough intensity. it may stimulate NTE by crossing over - important because it can retain false positive responses
111
factors that affect an individuals IA
- size and density of head and skull - type of transducers - AC vs BC - isnt uniform across frequency
112
masking rule 1A
when the difference between the AC threshold of the TE and the AC threshold of the NTE is > 40 dB
113
masking rule 1B
when the difference between the AC threshold of the TE and the BC threshold of the NTE is > 40 dB
114
masking rule 2
when the ABG is greater than 10 in one ear (TE) mask the opposite ear (NTE) in order to verify the BC threshold in the TE
115
effective masking level
amount of threshold shift in the masked ear produced by the addition of a given amount of noise
116
hood technique | -starting level
AC - AC threshold of the NTE plus 10 dB BC - AC threshold of NTE plus OE plus 10dB
117
hood technique
- each time patient responds to pure tone signal present to TE, increase the level of the masker in the NTE by 10 dB - each time patient does not respond increase the test signal in 5 dB until the patient responds again - do this until masking can be increased 3 consecutive times without producing a shift in threshold level of TE - this is plateau
118
factors that influence width of masking plateau
- AC threshold of masked ear - narrow plateau, higher, large ABG - BC threshold of TE - small ABG, wide plateau - IA - small ABG, wide plateau
119
narrowband noise
- a restriced band of frequencies surrounding a particular frequency to be masked - obtained by band - pass filtering a broadband noise - more effective maser than white or complex noise - used for masking in pure tone audiometry
120
central masking
- a threshold shift in the TE resulting from introduction of a masking signal into NTE that is not due to crossover - the elevation of threshold is produced by inhibition that is sent down from the auditory centers in the brain
121
overmasking
- occurs when a masking noise presented to the NTE if of sufficient intensity to shift the threshold in the TE beyond its true value - masking noise crosses from the masked ear to the TE by BC
122
masking dilemma
-occurs when both ears have big ABG and unsure which to mask
123
what info about speech do we want to obtain?
- threshold - pure tone - cross check - understanding at suprathreshold level - differential diagnosis - estimating communicative function
124
what is meant by functional hearing
-falsation or exaggeration of hearing ability for some conscious or unconscious reason
125
patient response modes
- verbal repetition - written responses - picture pointing
126
overmasking =
OM = EM NTE - IA > best BC TE
127
MLV advantages
-allows clinician to modify rate of presentation and determine SRT faster
128
MLV disadvantages
-difficult to monitor the test words to a consistent HL and impossible to present each spondaic word in the same manner to every patient
129
recorded list advantages
- standardizes composition and presentation of test list - better control of intensity of test items and ensures that the speech pattern of the recorded talker will be consistent with all patients
130
recorded list disadvantages
-may limit flexibility in selection of words and rate of exam
131
when is masking needed during speech testing
- if SRT of TE is 40 dB worse that BEST BC threshold of NTE at .5, 1, 2, or 4 Hz
132
SDT
- speech detection threshold - running speech detection - same as SAT
133
SPONDEE
- 2 syllable words that have equal stress on each syllable - lowest HTL at which 50% of list is correct - must agree with PTA within a 5-6 dB range
134
SRT
- speech recognition threshold - lowest hearing level is understand at least 50% of the time - should be in agreement with PTA - requires more intensity to recognize and repeat words - familiarization is key so comprehension of words are more clear
135
what is the dynamic range or range of comfortable loudness
- RCL is the difference in dB between the threshold for speech and the point at which speech becomes uncomfortably loud - determined by subtracting the SRT from the UCL - also called the dynamic range for speech
136
most comfortable loudness level
- MCL is the hearing level designated by a listener as most comfortable listening level for speech - running or continuous speech is most commonly used in hearing aid processes
137
uncomfortable loudness level
-UCL is the intensity at which speech becomes uncomfortably loud
138
word discrimination (recognition) testing
the ability to recognize monosyllabic words presented at a suprathreshold level -usually recorded by % correct responses
139
purposes for determining word recognition score
- to help determine site of lesion - to evaluate effectiveness of communication skills - to determine candidacy for surgery - to plan and evaluate aural rehabilitation programs - to evaluate hearing aid candidacy and select appropriate amplification - to assess central auditory function
140
presentation level
- usually 30-40 dB sensation level | - the presentation level of the words should be 30-40 dB above the SRT
141
carrier phrase
- phrase preceding stimulus word | - clinician peaks the VU meter on zero the last word of the carrier phrase
142
phonetically balanced word lists
- familiar monosyllabic words | - contains all phonetic elements in english with respect to frequency of their occurrence
143
half list vs. full list
50 - full - multiply number wrong by 2 and subtract from 100 20 - half - multiply number wrong by 4 and subtract from 100 *if miss more than 4 on 1/2 then you need 50 word list
144
signal to noise ratio
- the difference in dB between a signal (speed) and a noise presented to the same ear. - when speech has greater intensity than the noise, a positive sign is issued - when noise has a greater intensity then the sign is negative
145
performance intensity function
- PI - word recognition testing is completed at successively higher presentation levels - usually performed in order to determine 1. where the "maximum" or highest score lies to the poorer score 2. if performance decreases at the highest intensity levels *decline in hearing with increase in intensity is indicative of retrocochlear hearing loss
146
open set vs. closed set
open - not multiple choice | closed - multiple choise
147
rollover ratio
(PB max - PB min)/ PB max
148
norms for rollover ratio
0. 0 - 0.44 = normal, conductive or cochlear | 0. 45 - 1.0 = retrocochlear
149
redundancy vs. sensitivity
redundancy - less syllables more sentences sensitivity - less sentences more syllables
150
open set
``` PB-50 CID W-22 NU-6 PBK-50 HINT ```
151
closed set
``` california consonant PIT WIPI NUCHIPS SSI SPIN SIN ```
152
PB-50
- harvard psycho-acoustics lab - 1 syllable words - phonetically balanced - 30-40 dB SL - uncommon words * most commonly used
153
CID W-22
- central institute for deaf - 30 dB SL - test more intense levels * commonly used
154
NU-6
- northwestern - 40 dB SL - based off SRT * commonly used
155
PBK-50
-same as PB-50 but for kindergarten children aged 5-7
156
california consonant
- designed for patients with HF SNHL - patient views lists, marks words heard - high frequency - closed set - 100 monosyllabic words in 2 50 word lists
157
PIT
- picture identification task - nonverbal adults - CNC words represented by pictures are arranged into sets of 4 rhyming words
158
WIPI
- word intelligibility by picture identification - ages 3-6 - point to picture of word spoken by tester
159
NUCHIPS
- northwestern university childrens perception of speech | - similar to WIPI
160
SSI
- synthetic sentence identification - nonsense sentences task - ID sentences from list
161
SPIN
- speech perception in noise - stress the system - test with competition or noise - most elderly with HL do not use context as well - last word determines if correct - test w/ambient noise
162
SIN
- speech in noise - 4 talker babble used as noise - most commonly used w/hearing aids/amplification devices - 5 sentences
163
HINT
- hearing in noise test - sentences - open set - hearing aid - repeat back entire sentence
164
intrinsic
-pathways to CNS to extract info from our speech signal
165
extrinsic
- abundance of info is present in speech signal - hear only a part of speech signal and make sense of it - gets larger as content of speech signal increases
166
audibility index
- as AI decreases, hearing handicap increases - used as a counting tool to estimate WRS - dots represent 1% that contributes to speech intensity - more dots below threshold indicate an increase in better hearing in normal conversational speech at 6 ft
167
SRT | spondee threshold
ST - lowest threshold where at least 50% of spondees correctly identified - once 50% reached doesn't take much more to get to 100%
168
what is clinical decision analysis
-determine best test for a particular application
169
why is CDA important
-helps evaluate different tests and is a quantitative strategy to make clinical decisions
170
reliability
-consistency in results
171
validity
-correct results based on assessment
172
sensitivity
- the fraction of those with the disease correctly identified as positive by the test * *how well a test correctly diagnoses or IDs a disorder
173
specificity
- the fraction of those without the disease correctly identified as negative by the test * *how well the test correctly rejects an incorrect diagnosis
174
retrocochlear
beyond the cochlea
175
ASHA acceptable screening tool
- easy to administer - reliable - valid - sensitive - specific - safe & cost effective
176
pure tone average
500 + 1000 + 2000 / 3 = Hz
177
flat
threshold within 20 dB
178
rising
-better hearing at highest frequency
179
originators of SRT
- chaiklin ventry | - martin dowdy
180
0 dB HL
- standard reference | - reflects different SPL depending on freq
181
occlusion effects
1000 Hz - 10 dB 500 Hz - 20 dB 250 Hz - 30 dB
182
pure tone audiometry
- behavioral test used to determine hearing sensitivity | - to determine, type, degree, and configuration of hearing loss
183
calibration checks
- biological - psychoacoustic - electroacoustic or physical method
184
psychoacoustic
- not precise - obtain thresholds for group of people with normal hearing - if drifted more than 10 dB means audiometer has drifted out of calibration
185
electroacoustic
- physical method - sound pressure level - use sound level meter, coupler, microphone, and weight
186
calibration normality
0-2.5 dB - no correction needed 2. 5-7.5 - correction factor of 5 dB 7. 6 > - correction factor of 10 dB
187
white noise
a broadband noise with approx equal energy per cycle
188
complex noise
sawtooth - broadband of frequencies created by generating a low frequency tone in its harmonics - each succeeding harmonic has less intensity
189
speech noise
- filtered white noise that contains relatively more energy at lower frequencies than white noise - used to mask the NTE during speech testing
190
undermasking
-occurs when a masking noise presented to the NTE is of insufficient intensity to prevent the test signal from being heard in the NTE
191
reasons for determining SRT
- to find lowest level at which a person can identify speech - to determine the reference level for word recognition testing - to check the reliability of the PTA taken at 500,1000 and 2000 Hz - SRT should agree with PTA within 5-6 dB - sometimes used in evaluation and fitting of hearing aids