Exam 2 (Part 1) Flashcards
1
Q
List 8 warning signs of ear disease that should be referred for medical evaluation before proceeding with amplification?
A
Visible congenital or traumatic deformity of the ear.
History of active drainage from the ear within the previous 90 days.
History of sudden or rapidly progressive hearing loss within the previous 90 days.
Acute or chronic dizziness.
Unilateral hearing loss of sudden or recent onset within the previous 90 days.
Audiometric air-bone gap equal to or greater than 15 decibels at 500 hertz (Hz), 1,000 Hz, and 2,000 Hz.
Visible evidence of significant cerumen accumulation or a foreign body in the ear canal.
Pain or discomfort in the ear.
2
Q
proceeding to a solution by trial & error or rules that are loosely defined
A
heuristic decision making
3
Q
Gioia et al. (2015) found technology level recommendations were not based on outcome benefit, but instead on variables such as patient lifestyle as perceived by the hearing professional.
A
true
4
Q
recommendations of premium technology dramatically increased when professions PERCIEVED patient as
A
active vs. non-active
5
Q
Create a guide for the purpose of assisting your ability to recommend amplification based on patient preferences, degree of hearing loss and evidenced based research
A
recommendations of premium technology dramatically increased when professions PERCIEVED patient as active vs. non-active
Audiologists theorize more use equals more benefit from premium level technology
entry level or lower-level technology recommendations increases for patient’s over 70
active patients w/ poor speech discrimination only had a 17% chance of being recommended a premium technology while active patients with good speech discrimination increases to 68%.
6
Q
Prem vs. Entry level Tech
A
No significant difference in sentence recognition scores is found b/w premium and entry-level hearing aids, if directional microphones were available.
No significant difference in aided loudness existed b/w the premium and entry-level hearing aids.
Sound quality ratings are similar for premium and entry level technology.
Premium technology was preferred when subjects desired user-controlled DSP, streaming, convenience, & connectivity.
7
Q
when was prem tech preferred by subjects?
A
Premium technology was preferred when subjects desired user-controlled DSP, streaming, convenience, & connectivity.
8
Q
Wu et al (2019) while premium technology appeared to improve intelligibility and localization in laboratories, these benefits did not translate to the real world.
A
true
9
Q
2 individual factors that may impact performance, preference, and real-world outcomes of prem tech
A
individual’s ability to accept background noise AND the listening demands of an individual’s environment.
10
Q
Pyler et al (2021) concluded premium technology offers the most benefit to:
A
Individuals with poor ANL scores (tolerance to noise)
Premium technology improved aided ANL score
Individuals regularly communicating in large group or demanding settings
11
Q
what is the evidence based recommendation when recommending amplification
A
use of multi-level demonstration level technology during device trials allows patient to compare entry-level vs. premium level in realistic environments
12
Q
How many frequency shaping bands are needed to optimize a hearing aid fitting for a flat or sloping HL
A
Flat or sloping hearing loss:
4 bands provides sufficient frequency-shaping flexibility
13
Q
How many frequency shaping bands are needed to optimize a hearing aid fitting for a steeply sloping loss
A
Steeply sloping losses
Research suggests increasing to 7 bands allows output adjustments to narrower frequency ranges (2001)
14
Q
act as a frequency specific volume “handle” to maximize audibility w/o changing compression
A
frequency shaping bands
15
Q
adjust compression ratios to shape output into the individual’s dynamic range
A
compression shaping channels
16
Q
How many compression shaping channels are needed to optimize a hearing aid fitting?
A
9 frequency shaping channels should accommodate majority of audiograms
17
Q
Increasing the number of frequency shaping bands from 3 to 18 significantly improved speech audibility for a steeply sloping hearing loss BUT increasing frequency shaping channels from 3 to 18 supplied little benefit
A
true
18
Q
An organizational tool designed to systematically review a set of treatment options
A
decision aid
19
Q
List counseling strategies that improve retention and recall of recommendations
A
presentation needs to include concrete advice
explain in easy to understand terms
present most important info first
stress importance of info you want the person to recall
dont present too much info
repeat most important things
understand what it is the person wants
provide written, graphical, and picture material for the information
20
Q
what are the REM steps
A
- input audio, choose protocol and target info
- calibrate and position patient with equipment
- otoscopy and place probe in the ear
- unaided measurements
- occluded measurements
- calibrate open fit?
- aided measurements & matching targets
21
Q
what does all systems have
A
external speaker that generates variety of input signals
22
Q
what is the ear level probe module
A
connects PT to the REM system
has ref mic, probe mic, probe tube, & retenton cord
23
Q
what is the ref mic
A
monitor and calibrate the soundfield speaker output, maintaining the desired signal intensity at the measurement point
makes sure the signal arriving to probe module is the intended intensity
24
Q
what is the retention cord
A
stabilize and maintain the reference microphone’s position
Blue stretchy coard
25
probe tube
measure the intensity of the signal arriving to the TM
26
prob mic
collects and measures sound from the probe tube attached to it
Stem
27
Output requirements to achieve binaural benefit
Aided output must be 15dB
28
describe a type one signal
Brief puretone signal swept over a variety of frequencies
brief pure tone signal presented and they are used because they can measure highest output coming out of the HA (make sure max power output is not exceeding PT LDL)
29
waht is the benefit of type I signals
Type I signals drive a higher output than speech signals
They’re used to accurately measure maximum loudness when verifying MPO
30
what are type I signal limitations
Does not show affect of compression or channel interactions on the output signal
DFS signals attenuate Type I signals when its activated
31
how does DFS attenuate type 1 signals
if unit uses swept instead of pulsed, activates DFS and HA attenuates the signal and you dont see true output of the HA & with speech we are getting soft sounds adding gain and compressing loud sounds and the pure tone signal dones’t show us compression, doesn’t show if we put it into persons dynamic range (cannot see the compression weve added and the impact CR have )
32
describe type II signals
complex “speech-like” signals
Broadband signal consisting of random frequencies occurring at different intensities
(LF & HF very rapidly presented, soft and louder signals rapidly varying and changing as we speak), testing audiblity for soft, moderate and loud inputs (loud is different than MPO) of speech
33
benefit of type II signals
Its unpredictable moment-to-moment amplitude changes mimics speech
34
limitation to type II signals
Rapid gain changes may not truly show a device’s response to different spectral shapes in the succeeding sounds
might not see all of the spectral issues because we cannot capture every little detail
35
types of type II signals
standardized and non standardized
36
Calibrated speech signals providie
repeatable, consistent signals to verify a device’s ability to meet prescriptive targets for output & frequency response
37
what are standardized speech signals (type II)
contain all sounds within the speech spectrum within a 10 second passage
38
ex of standardized speech signals
Speechmap- speech signals filtered to provide the long-term average speech spectrum (LTASS)
ISTS- International Speech Test Signal: 6 female talkers reading the same passage in American English, Arabic, Chinese, French, German and Spanish
ICRA- International Collegium for Rehabilitative Audiology: distorted speech signal is a recording of an English-speaking talker that has been digitally modified to make the speech largely unintelligible
39
what is the speech map
speech signals filtered to provide the long-term average speech spectrum (LTASS)
standardized speech signal
40
not used for amplification programming
non standardized signals
41
what are non standardized signals (Type II)
Measures output of different signals
Good for counceling
The intensities, frequencies are less repeatable which is why we cannot use them to program
Noncalibrated signals are helpful in counseling, but cannot be used for prescriptive fittings
42
benefit to non standardized
signals lack standardized repeatabilitySpeech- female
Speech- child
Speech- live
Measures the LTASS and speech envelope of any audible signal over 10 seconds
Use: probe microphone acts as a spectrum analyzer and “test signal” is typically communication partner’s voice
Provide an excellent demonstration of output based on communication partners speech
43
what is the LTASS
Long-Term Average Speech Spectrum
frequency-dependent measure of time averaged sound pressure level of speech
change with varying vocal effort, microphone position, and language.
44
Vocal effort primarily influences
mid-frequency LTASS average.
45
Microphones azimuthal position strongly influences
high-frequency LTASS average.
46
Tonal languages influences
low frequency LTASS average
47
Explain how a signals LTASS is calculated
LTASS is calculated by averaging a measured signal for 10 seconds
48
Speech envelope has a crest factor of ______dB & valleys of_____ dB
+12
- 18
49
The Speech Intelligibility Index (SII) is maximized when
entire speech is above threshold.
50
Speech signals with different intensities will have a the same LTASS
false
different
51
An individual’s LTASS will be the same as the LTASS of a standardized speech signal
false
it will differ
52
changes depending on the intensity of the speech signal
LTASS
53
measured over a 10 s period of time
LTASS
54
measurement showing the dynamic range of the speech signal arriving to the tympanic membrane
measured speech envelope
55
The difference between the valleys (softest signal) and peaks (loudest signal) of speech is ______- SPL
~30dB
56
if PT SII is low, might look at lower part of speech envelope and see if you can raise just the soft sounds to make louder to get more audibility and max SII
true
57
what is the LTASS “SPEECH ENVELOPE”
Visual representation of modulated speech sounds
Speech envelope has a crest factor of +12 dB & valleys of - 18 dB
These two lines define the representative dynamic range of normal conversational speech over time (a 10 sec. measurement)
58
louder speech sounds re about 12 dB louder than LTASS
tru
59
valles of soft sounds rea bout 18 dB softer than LTASS
true
60
Difference bw threshold & LDL represents \
dynamic range
61
what is the substitution method calibration protocol
Done before the PT arrives, placed at where subject’s head would be, stored as a reference point, used to calibrate the reference mic and probe
Sound level measurement mic is placed at subject’s position
Calibration is stored & used as reference point
62
limitation to the substitution calibration method
Absence of subject’s head/body reduces precision
Changes in location/movment of subject impacts results
63
what are the modified pressure methods
Modified pressure “concurrent equalization
Modified pressure “stored equalization”
64
describe Modified pressure “concurrent equalization”
reference mic monitors test signal throughout test to equalize and adjust, calibration signal replays every 10 seconds (pink noise segment)
ref mic constantly monitors test signal throughout testing to equalize & adjust signal intensity
Recalibration happens automatically and calibrated signal replays every 10 s throughout measurement process
65
describe the Modified pressure “stored equalization”
probe is calibrated one time on PT’s ear & stored for fitting process
Used when amp sound can leak out of open domes & interact w/ ref mic
Used to avoid ref mic contamination (stops it)
66
happens when amp output escapes ear canal through open dome
reference mic contamination
67
Head movement during measurement can impact final recording
Modified pressure “stored equalization”
68
what is reference mic contamination
Ref mic measures and reacts to the intensity of HA output signal lowering the intensity of speaker’s input signal
Amp signal goes into the ear & leaks out of ear w/ open fit reaching the ref mic sitting outside of the ear tricking it into thinking the speaker intensity is louder than it is causing the speaker to turn down so now the signal arriving to the ™ is softer than the true response that is arriving to the mic
69
Why does the probe module calibration process result in an “acoustic transparency” b/w the reference mic and probe tube?
probe microphone module cannot be physically located in the ear canal; the probe tube serves as an extension to the probe microphone
Probe tube tip is placed directly over the reference microphone during calibration. This protocol accounts for the different intensities arriving to the probe microphone module’s reference mic and through the probe tube.
The unit mathematically adjusts the intensity differences removing the tube’s resonance effects.
This procedure makes the probe tube “acoustically invisible”
The modified pressure concurrent equalization calibration signal arrives simultaneously to the probe tip and reference mic during. Therefore, the “distance” b/w the reference mic and probe tube tip becomes acoustically invisible
70
describe the protocol for calibration
Place tip of probe directly over reference mic
Ref mic must face speakers during calibration
Hold probe module 6” to 36” away from the speaker
Keep your fingers and body out of the way!
Present calibration signal
71
Explain the concepts and ANSI recommendations surrounding effective measurement “working distances” for equipment, patient position and audiologist position
defines “working distance” as the allowable distance b/w the patient and the speaker (18”-36”).
The nearest reflective surfaces and the tester should be 2 times farther than the working distance during testing.
That means you stand 36” to 64” away!
Ambient room noise must be 10 dB lower than the REM signal to minimize effect on test results.
Horizontal plane: 0º azimuth: greatest reliability
45º: may be used by some
90º: results in significant variability/errors
Vertical plane: to accurately measure high frequency output, the speaker should be level with the patient’s ear.
72
0º azimuth
GREATEST RELIABILITY
73
45º
used by some
74
90º:
results in significant variability/errors
75
what are we looking for with otoscopy before probe tube placement
Watch direction/angle of EAC
Helps w/ probe tube insertion
Check for cerumen/debris
Can interfere/plug tube and interfere with placement
Insert at an angle to avoid cerume or remove it before
76
describe probe module placement
The reference mic must face the room (away from the patient’s neck)
Use the blue cord to stabilize the probe module under the earlobe
Clip the probe module cable to the opposite side to stabilize the location of the reference mic
Slip the probe behind the blue cord so the black marker lays in the inter-tragal notch
Add lubricant to the middle of probe tube and/or mold to reduce slit leaks
The black marker must be moved to the inter-tragal notch once depth of insertion is confirmed to ensure the tube doesn’t move after placement
77
what are the probe tube insertion methods
otoscopic method
constant depth method
acoustic method
geometric postition method
78
otoscopic method
lead to bump and pull, not pleasant for PT, other methods are more precise
79
constant depth method
measure black bead (tube marker) to premeasured position
Distance from intertragal notch to TM is about:
Male: ~30 mm
Female: ~28 mm
Pediatric: move marker to ~20-25 mm
Using these measurements the tube tip will be within 2-5 mm of TM for the average patient
80
Distance from intertragal notch to TM in
Male
~30 mm
81
Distance from intertragal notch to TM in
female
~28 mm
82
pediatric
~20-25 mm
83
acoustic method
Present a 65 dB SPL pink noise signal while inserting probe tube.
Gently insert the probe tube while keeping an eye on the high frequency notch
The probe is w/i 5mm of the TN when the notch is no longer dragging the gain curve down in the high-frequencies (no > 5 dB at 6k Hz)
Once the measurement is stabilized move the probe tube marker into position.
84
geometric position method
used for squirmy/uncooperative PTs, probe placed along outer ridge of intertragal notch of device
Probe tip extends 3- 5 mm beyond the tip of the earmold.
The extent to which this insertion depth is appropriate will also depend on the length of the earmold. For instance, shorter length canals (e.g., not beyond the second bend), it is likely that the probe tube will not be close enough to the eardrum to accurately assess the high frequencies.
Mark the probe tube length
85
RE
real ear measures acquired on a PT’s ear
86
U
unaided
how your ear resonates sound naturally
87
o
occluded
what happens to the resonance in your eaer qhen we block it
88
a
what happens in ear when HA is turned on
89
gain
HL
Difference bw input level arrive to eaer and output level arriving to ™
difference between the output intensity and the input intensity
How much gain did we add to each frequency in order to make it audible to the PT
Expect a low SPL value
90
low SPL value
gain
91
high SPL value >90
response
92
r
response (SPL)
Output arriving at the ™
Absolute measure of SPL output arriving at the ™
Expect a high SPL value >90 for acronyms ending in R
93
Intensity at the TM
reur
94
Gain differential
reug
95
the natural resonance resulting from the pinna and ear canal effect that the patient walked in the door with
REUR
96
the insertion loss that results from the mold/dome
REOR
97
the output arriving to the TM when aid is turned on
REAR
98
the amount of gain added to the input signal when the aid is turned on
REIG
99
the MPO that’s arriving to the TM
MPO/RESR/REAR85/90-
100
difference between the SPL resonance of a 2cc coupler and the SPL resonance of the real ear
RECD
101
what is REUR
The measurement of the absolute SPL level of an open ear canal resonance, across all frequencies, at the tympanic membrane (input+ gain+ resonance= output)
102
how does REUR changd
Changes due to ear canal differences
Size, texture, shape, or presence of abnormal anatomy
Age: pediatric, adult, elderly
One person can have 2 different REUR’s
103
what is REUG
The measurement of gain increase resulting from pinna, ear canal, and head diffraction effects, as measured in an open ear canal.
REUR - input level = REUG.
Input level subtracted from the real ear unaided response to get the gain
104
why do we do REUR/REUG
Knowing the PT’s ear canal resonance improves accuracy of prescriptive fitting
Everyone has a different ear canal resonance
105
how do we measure REUR
Conduct otoscopic examination.
Place patient at appropriate distance/azimuth from loudspeaker (e.g., 0.5 m/0 degree).
Place probe tube into open ear canal to appropriate depth (e.g., within 5 mm of eardrum).
Pre-measure probe tube and move marker to guide placement
On Audioscan, go to On-Ear test measurements, Speech map, then Turn on Pink Noise 65 signal and insert probe
Go until HF output confirms tip is w/in 5mm of ™
Look at HF notches
Probe is w/in 5mm of ™ when the notch is no longer dragging the gain curve down in the HFs (not >5 dB at 6 kHz)
Adjust the marker once measurement stabalizes
Confirm cerumen didn’t block probe tip
Tip: whip and place probe over reference mic while prob mic remains hanging on the ear
Flat response using pink noise indicates probe is clean
Select desired input level and test signal type.
Present at 65 dB SPL pink noise signal to the unoccluded ear canal
Present and record the measurement
106
as ear canal is smaller it increases in SPL so peds do not need as much gain added than an adults
true
107
Resonance changes as you age because the reflection changes
true
108
How will standing waves impact REUR and REAR measurements? How is this resolved?
Probe tip location must be w/i 5 mm of the TM to provide an accurate assessment of SPL across the frequency range, particularly in the higher frequencies.
Placement more than 5 mm from the TM creates acoustic nulls resulting from standing waves
Those nulls attenuate the measured SPL tricking you into believing the high frequency output is lower and underestimating the actual output of the device.
109
what is REOR
A measurement of the attenuation of an input signal, across all frequencies, when a hearing aid is inserted and turned off
110
what is REOG
A measurement of the input and output SPL (gain reduction), across frequencies, when the hearing aid is inserted and turned off.
111
tells you the impact that the fitting tip, earmold or custom hearing aid has on the sound reaching the ear.
REOR
112
drop in change of resonance
insertion loss
113
REOR verigies
Vent effect or slit leak frequencies
Transparency of open dome fit
If coupler will meet the patient’s prescriptive needs
114
limit ability to add gain at those frequencies
vent effect/slit leaks
115
<1kHz shows no insertion loss for any dome suggesting that even a power dome cant hold LF energy in the ear canal (why we dont use a dome if loss is >40dB because they do not hold output in the ear canal
true
116
Greater insertion loss in HF than LF because mass impacts LF more than HF
false
impacts HF more
117
how do open, tulip and power domes affect insertion
open domes shouldn’t goss insertion loss
Tulip - some insertion loss
Power - most occluding; greatest insertion loss; isn’t attenuating below around 750 Hz
118
how does open dome effect insertion loss
doesn’t create much insertion loss at all; all input signal is arriving to ™ with little change o it
119
how is REOR measured
Conduct otoscopic examination.
Place patient at appropriate distance/azimuth from loudspeaker (e.g., 0.5 m/0 degree).
Place probe tube into open ear canal to appropriate depth (e.g., within 5 mm of eardrum; beyond sound bore of earpiece).
Note: If REOR/REOG is being used for comparison to REUR/REUG, ensure the probe tube remains in the same location for all measurements.
Insert hearing aid into client’s ear canal, being sure to maintain probe tube location.
Ensure the hearing aid is muted or turned off.
Select desired input level and test signal type.
65 dB PINK NOISE signal on test #2
Present and record the measurement
.Select CONTINUE (or record) when the response stabilizes to measure REOR
120
why do we measure REOR
If the vent effect is releasing low frequencies as expected
Which LF are released due to the vent effect
To determine if the vent introduced undesired standing waves
to see if the vent effect is performing as expected
121
This measurement identifies which low frequencies are released due to the vent effect
REOR
122
You will not be able to increase the output within the “vent effect” frequency range. Additional gain is be released through the vent!
true
123
represents the amount of the signal that comes to the ear, pushes thorugh the vent or the slit leaks and arriving at the TM
vent effect
124
amount of energy arriving at ear and is stopped brcause of the big mass in the ear
insertion loss
125
Vent effect directly correlates with SNR advantage (directivity index) provided by directional microphones
true
126
Increased venting allows more audibility of direct signal which increasees SNR advantage
false
reduces
127
If you have Occluding mold get a lot of direct signal and HA doesn’t manage this so they have a lower directivity index
false
open dome
128
open dome, directivity index is higher and get more directional mic benefit
false
Occluding mold
129
what is REAR
Absolute aided output and frequency response when a HA is turned on
HA is on and turned on, output is the aided output to the ™ compared to the unaided response in yellow (just seeing gain)
130
how to measure REAR
1.Conduct otoscopic examination.
2.Place patient at appropriate distance/azimuth from loudspeaker (e.g., 0.5 m/0 degree).
3.Place probe tube into open ear canal to appropriate depth (e.g., within 5 mm of eardrum; beyond sound bore of earpiece).
Note: If REAR/REAG is being used for insertion gain purposes, ensure the probe tube remains in the same location used for the REUR/REUG.
4.Insert hearing aid into client’s ear canal, being sure to maintain probe tube location.
5.Turn hearing aid on at desired programmed settings.
Note: If significant venting (e.g., open-fit device), first calibrate sound field using “stored calibration” with hearing aid in place and turned off or muted prior to testing.
6.Select desired input level and test signal type
7. Present and record the measurement
131
why do we measure REAR
o view device’s absolute aided output in a unique ear canal
If you don’t measure it, you don’t know if you’ve met your objective!!!
DSL prescriptive targets specifies REAR (OUTPUT) targets for signals arriving to the ™
132
Average adult (peak resonance
~2-4k Hz)
133
Mastoidectomy (peak resonance
~ 1- 2k Hz)
134
Pediatrics (peak resonance
~ 6k Hz)
135
Perforation (peak resonance
change based on change to volume) - no set pattern because no perf is the same
136
does the depth of receiver change REAR
yes
deeper higher (more gain) and shallower is lower (less gain)
137
what is REIG
Measures the amount of GAIN needed to overcome the insertion loss (REOR) and restore audibility of the signal
The difference between the AIDED response and the UNAIDED response of the ear canal
REAR- REUR = REIG
138
Helps us to know how to adjust gain to make sound sound natural
REIG
139
how to measure REIG
1.Conduct an REUR.
2.Conduct a REAR as described above, ensuring the same sound field conditions and probe tube placement location as the REUR.
3.Subtract the REUR from the REAR or subtract the REUG from the REAG. REM systems will perform this subtraction automatically and plot the resulting REIG on the screen for you.
4.Adjust the hearing aid programming so that the REAR (REAG) and thus the resulting calculation of the REIG provides the closest match to the target REIG across frequencies
140
why do we measure REIG
We adjust GAIN for soft, moderate and loud input signals within the programming software to achieve the desired real ear insertion gain (REIG)
NAL prescriptive targets specifies REIG (GAIN) targets to ensure loudness equalization is maintained
How much gain is needed to reach the target (what is output needed to arrive to ™ - DSL)
141
when resonances are typical
nal
142
resonance are not typical
dsl
143
what is REAR 85/90 (MPO)
MPO & Real Ear Saturation Response (RESR)
Assessment of mpo
Measures intensity of output singal arriving to the TM , when input signal is
sufficiently intense to drive the device to its maximum power output level
MPO that is arriving to the TM
144
REAR 85/90 (MPO)how to measureREAR 85/90 (MPO)
Present Type 1 input signal
Test box technique
90 dB input signal is compared to LDL data
Ear level technique
85 dB input signal is compared to LDL data
145
WHY DO WE TEST
REAR 85/90 (MPO
To document the maximum SPL that the hearing aid can deliver to the user’s ear for loud sounds
To ensure MPO settings do not exceed loudness discomfort levels
In situ, 85 dB signal, should be perceived as “loud but ok”
146
What is RECD
A sound generating transducer produces a signal in the ear canal and in a 2cc coupler to measure the resonance of each.
RECD is the difference in decibels across frequencies, between an ear canal resonance and the resonance of the 2cc coupler
the difference between the SPL resonance of a 2cc coupler and the SPL resonance of the real ear
147
Recognize the impact incorrect physical acoustic parameter settings could have on the calculated gain and output of the device
The information you enter can change how the hearing aid functions completely. Algorithmic decisions to add or reduce gain vary based on the vent effect, sound bore size/shape, and receiver properties so entering them incorrectly changes the gain and output of the device
148
What is the difference between modifying bands and channels?
Adjusting Bands (columns - up and down) allows you to adjust the gain without changing the compression ratio
Adjusting Channels (rows - side to side) allows you to change gain for either SOFT or LOUD input levels. The compression ratio changes with each adjustment.
149
Learn to calculate threshold-based insertion gain requirements using the “half gain” fitting formula
“Half gain rule” found that most people wanted gain that equaled ½ the threshold of the loss
Calculated gain targets at 50% of the threshold loss
150
strives for an output that's audible and comfortable. It does not consider the relative importance of specific freq to speech recognition
loudness normalization
151
This is an output based formula that uses an individual's perception of loudness to create REAR Output targets.
loudness normalization
152
explain REAR output targets
Soft signals are increased until they are audible & perceived as soft
Moderately loud louds are increased or adjusted until they are perceived as comfortable
Loud signals are adjusted until they are perceived as loud but okay
153
low frequency signals have more energy than high frequency
increases the intensity of mid and high frequencies until their energy equals the lows.
loudness equalization
154
What does it mean when a prescriptive formula is proprietary
It means it was developed by manufacturers
It is okay to use the proprietary formula from the manufacturers that is based off the average ear but make sure you double check that it will work for the patient
155
Loudness equalization formula
nal nl2
156
Explain the RMSE concept and the recommended fitting criteria
Root Mean Squared Error
Considers how close the measured output is to the prescribed target, you want them as close as possible (within 5 dB) to ensure the hearing aid is providing adequate audibly of the important speech energy without feedback or loudness discomfort
157
Loudness normalization formula
dsl 5
158
Maximized audibility formula
Speech Intelligibility Index (SII) Audibility targets
159
REM targets aren’t available, but NAL-NL2 targets can be used
Proprietary formula- developed by manufacturers
160
Difference bw HA1 and HA2
smaller one, used for custom style hearing aids
Meets ansi standard, #1 standard for RECD
longer one, used for BTE
#2 standard
161
Real ear is a lot different from patient to patient
true
162
Explain why it is beneficial to measure the RECD on every adult’s ear canal to improve the accuracy of the gain and output targets?
Can put the data into a PTs records and do not have to measure again unless there is a sig change
Like weight loss because it changes the ear canal size
163
why do we measure RECD on adults ears
Accurately converts an individual’s HL audiometric thresholds, measured using inserts, to dB SPL values
most useful application of the RECD is in the prediction of real-ear output when hearing aid measurements are made in the test box.
PT doesn't need to be present
164
Using RECD conversion values calculates ear canal SPL within _____ dB creating customized conversion values to create accurate fitting targets.
1
165
Define RECD based on ANSI Standards
ANSI Standard - ONLY USES HA-1
RECD measurement can be made with a custom earmold or EAR insert
The same coupler for BOTH measurements
166
RECD (RM500SL & Verifit 1): the “difference” should be a ____ value
positive
167
A negative LF value suggests
a slit leak is present
168
When pink goes below green in LF
slit leak = acting like a vent effect
169
Negative LF results are expected when
perfs or PE tubes are present
170
Negative RECD >10dB in the 4-6 kHz region
probe tube is blocked
171
when ear canal is smaller than average
SPL increases
172
when ear canal is larger than average
spl decreases
173
Follow the test protocol, to program and verify hearing aids and prepare to interpret measured findings. The correct order to do this is:
Measure REUR
Measure REOR
Measure / adjust frequency shaping bands
Measure / adjust compression shaping channel for soft inputs
Measure / adjust compression shaping channel for loud inputs
Measure / adjust MPO
174
Prescriptive targets specify the REIG (GAIN) or REAR (OUTPUT) needed at each audiometric frequency
true
175
the process that let’s us see if our prescriptive formula provides sufficient output
j
verification
176
the process that let’s us see if the patient thinks our choices were beneficial
validation
177
Adjust compression ratio to optimize detection of soft input signals or reduce loud input signals for increased comfort
true
178
adjusting ROWS
compression
179
Making adjustments to 55dB input adjusts what portion of the speech envelope
the bottom portion of the speech envelope
180
Making adjustments to 75dB input signal adjusts adjusts what portion of the speech envelope
the top portion of the speech envelope
181
what is the purpose of verifying MPO
ensure tolerance of loud input signals
set MPO to an intensity that is close but about 5 dB under PT’s LDL
182
M symbol represents
mcl
183
E symbol on its side represents
ldl
184
A symbol represents
aided soundfield audiogram
185
Bone scores are only added for A-B gaps
>15dB HL
186
Algorithmic decisions to add or reduce gain vary the based on the
vent effect, sound bore size/shape, and receiver properties
187
Output is greater the more experienced you are in the software
true
188
Closer the lines are the lower the compression ratio is
false
higher
189
max output available with the algorithm
black line (starkey)
190
what is the purpose of running digital feedback suppression
A calibration signal identifies the feedback path to apply a feedback cancelling algorithm
191
Each manufacturer manages feedback suppression differently. Why is it important to know which method is used for the brand dispensed
May attenuate output by a certain amount once feedback path is identified
May estimate the maximum amount of stable gain available
May calibrate feedback cancellation filter and add out-of–phase signal
May use a combination of all of the above
192
Further lines go apart
more linear
193
The closer they are the more compression that is added
true
194
If we shift tk up and down it impacts signal at kneepoint but not the rest of the signal
true
195
Leave HF and present where it is and transpose HF signals down into the LF range to make them audible
spectral warping
196
Recognize the impact incorrect physical acoustic parameter settings could have on the calculated gain and output of a device
gain/output reduced in LF due to vent setting
HF gain/output is limited by selected vent size
197
The band is adjusted so the LTASS is w/i _____dB of the prescriptive target
5
198
Increasing soft gain will increase
CR
199
Increasing soft gain will increase CR
what does this improve
This adjustment improves audibility of soft sounds
200
Increase of HF soft
more audibility of soft sounds
201
Increase LF soft
increase in background but can give LF soft speech signals
202
Decreasing soft gain will
decrease cr
203
Decreasing soft gain will decrease CR
This adjustment
reduces audibility of soft sounds.
Reducing LF soft sounds can help with background noise (reduces it)
204
Increasing loud gain will
decrease cr
205
Increasing loud gain will decrease CR
This adjustment can
make the signal sound crisper or clearer
Takes away some of the distortion
206
Decreasing loud gain will
incrase cr
207
Decreasing loud gain will increase CR
This adjustment improves
comfort for loud sounds
208
MPO adjustments lower the threshold kneepoint
activate compression at a lower intensity
209
MPO adjustments ONLY act on input signals _____ dB SPL
>90
210
Raising the MPO can make the device sound
clearer, brighter, crisper
211
setting MPO too high
Set it too high and patients will describe discomfort for signals >90 dB SPL
212
set MPO too low
Setting it too low unnecessarily reduces output intensity
Speech perceived as muffled, dull, distorted, squashed
213
Notice MPO reductions in my i/o curve does not change compression settings below the knee point. This adjustment ONLY impacts the kneepoint and louder sounds
true
214
Raising mpo
crisper sound for some to get some more clarity
215
Too high mpo
loud sounds are too loud and uncomfy
216
too low mpo
complain sound quality is muffled
217
It is recommended that frequency lowering be disabled for the first ______ weeks after fitting the device.
4-6
218
Steps for Programming
1.Calibrate On-ear probe microphone
2.Complete REUR in SpeechMap (pink/65 dB)
3.Complete REOR (pink/ 65)
4.Connect device
5.Select prescriptive target (NAL-NL2)
6.Define acoustic parameters based on audiometric configuration
7.Set experience level and best fit all memories
8.Run DFS calibration
9.Verify 65 dB Speech-standard signal adjusting frequency shaping bands (gain columns) to NAL-NL2 target
10.Verify 55 dB Speech-standard signal adjusting compression shaping channels (gain rows) to NAL-NL2 target
11.Verify 75 dB Speech-standard signal adjusting compression shaping channels (gain rows) to NAL-NL2 target
Verify and adjust MPO
219
Learn to calculate threshold-based insertion gain requirements using the “half gain” fitting formula
Half Gain fitting formula – the gain applied is the threshold divided by 2 – if there is a 40 dB loss, you add 20 dB of gain. Very basic, but most modern formulas are based on the half gain fitting formula.
220
describe the theory differences behind loudness normalization and loudness equalization
LN: DSL – Desired Sensation Level - max audibility to assist w/ L development
-Strives for a comfortable and audible output, does not consider relative importance of frequencies for speech perception.
-Focuses on how much sound has to arrive at TM for soft, moderate or loud perception.
-LF dominate perceptions of loudness
LE:NAL NL1 & NL2– National Acoustic Laboratory
-Balances perception of loudness over range of frequencies
-Increases intensity of mid and high freq until their intensity matches the low frequencies.
-Recognizes audibility of mid and high is important for speech perception / intelligibility.
221
Which formula uses REAR targets, which one uses REIG targets? Differentiate the use of output and gain targets.
LN: -Uses REAR “OUTPUT” targets
Soft signals increased until audible and perceived as soft.
Moderately loud signals increased until just perceived as comfortable
Loud increased to loud but OK.
-Formula provides output targets for soft, moderate, loud, & MPO settings
LE: Uses REIG targets.
-Looks at threshold and audibility then decides how much gain needs to be added.
-Equalizing energy, not intensity.
-Take HF energy which is weaker and vibrate less than LF and makes them stronger
222
DSL 5.0 vs NAL-NL2
-DSL adult formula reduces mid-freq gain by 7dB
-Milder thresh = low TK (~30 dB SPL)
-Sev thresh = higher TK (~60 dB SPL)
-Too much gain of soft results in loss of intelligibility when loss is severe
-DSL for peds is louder in mids than in adults
-Limitation: doesn’t account for ABG that is common in child population
NL2: -Early uses Lybarger ½ gain rule, calculates gain targets as 50% threshold loss
-Revised formula: calculates gain targets as 46% threshold loss, based on SII (more gain is added to sounds contributing most to speech intelligibility)
223
DSL adult formula reduces mid-freq gain by
7dB
224
Strives for a comfortable and audible output, does not consider relative importance of frequencies for speech perception.
LN
225
Focuses on how much sound has to arrive at TM for soft, moderate or loud perception.
LN
226
LF dominate perceptions of loudness
LN
227
Balances perception of loudness over range of frequencies
LE
228
Increases intensity of mid and high freq until their intensity matches the low frequencies.
LE
229
Recognizes audibility of mid and high is important for speech perception / intelligibility.
LE
230
Uses REAR “OUTPUT” targets
Soft signals increased until audible and perceived as soft.
Moderately loud signals increased until just perceived as comfortable
Loud increased to loud but OK.
LN
231
Uses REIG targets.
-Looks at threshold and audibility then decides how much gain needs to be added.
-Equalizing energy, not intensity.
-Take HF energy which is weaker and vibrate less than LF and makes them stronger
LE
232
-Milder thresh =
low TK (~30 dB SPL)
233
Sev thresh =
higher TK (~60 dB SPL)
234
Too much gain of soft results in loss of intelligibility when loss is
severe
235
DSL for peds is louder in mids than in adults
true
236
Which prescription provides targets for tonal languages?
NAL – lower frequency targets for tonal languages
237
Which formula supplies MPO targets?
MPO targets are supplied by DSL
238
Which formula supplies targets for A/B gaps?
DSL has the same output targets regardless of ABG input
NAL-NL2 provides Air Bone Gap targets.
-More gain added to overcome attenuation from mechanical loss
-25% of ABG is added
239
Name the formula used for severe to profound losses
-DSL will shift TK to 60 dB SPL (Higher TK), expansion is applied to low input
-multi-stage WDRC applied to input to expand DR
NAL RP - Gain calculated at 66% of threshold loss instead of 46%
240
Which formula supports language development?
DSL - max audibility to assist with language development
