HT I Final
Because it is not possible to prescribe OSPL90 with complete precision, the suitability of ________ _________ should be evaluated before the patient leaves the clinic. This can be done with REM or by asking the patient to report the loudness of intense sounds.
Maximum output
The ________ _________ ________ ________ (MEMS) microphone uses state-of-the-art silicon-etching technology.
Micro-electro-mechanical systems
The most effective way to make speech more intelligible is to place the _________ near the lips of the person talking.
Microphone
__________________-Apply a mechanical vibration to the middle ear system or round window, bypassing the need for an acoustical output form the hearing aid
Middle ear implant
___________ and __________ maximize speech intelligibility, subject to the overall loudness of speech at any level being no more than that perceived by a normal-hearing person
NAL-NL1 and NAL-NL2
The NAL and NAL-R prescriptions were updated to account for severe and profound hearing losses; the updated prescriptive approach is known as ________ .
NAL-RP
Through HIMSA, all manufacturers have adopted a common standard for storing data and sending information from computers for the programming of hearing aids. The standard is called _________
NOAH
Because hearing aids amplify sound and can do so at high levels for extended periods of time, over-amplification can cause a ________ _________ hearing loss, even for someone who has an existing hearing loss.
Noise induced
___________: amount of gain is dependent of input level ; slope of 2:1
Nonlinear
The _________ is an estimate (or measure) of the maximum SPL that a hearing aid can produce. This value should be high enough to avoid signal saturation but not be so high that it would cause the hearing aid wearer discomfort from excessive amplification.
OSPL90
________ fittings are those that have no intentional air path between the inner part of the ear canal and the outside air.
Occluded
The _________ polar pattern represents equal sensitivity to sounds from any direction.
Omni-directional
The _________ polar pattern represents equal sensitivity to sounds from any direction.
Omnidirectional
________ fittings are those that leave the canal almost completely open for its entire length; often used for persons with better hearing in the low frequencies.
Open
___________ - ___________ = gain
Output - Input
Individualized hearing aid prescriptions not only prescribe a frequency-gain response but a frequency-output response. The maximum output response of the hearing aid can be calculated by using which of the following guidelines?
Output = 100 dB SPL + 25% of the hearing threshold at that frequency.
The Prescription of Gain and Output prescriptive fitting procedure has a short-hand name of _________ .
POGO
________________- rolls off in low frequencies, but not high frequencies; recommends more amplification in high frequencies
POGO II
________ ________ are problems an individual may experience in involvement in life situations. Examples include the hearing disability causing the patient to refrain from activities that he/she would otherwise do, or cause the patient to have negative feelings about life.
Participation restriction
What happens when the signal exceeds the amplifier or receiver capacity?
Peak Clipping
_________-Describes the timing of a sound, or one component of a sound, relative to some other aspect of the sound or relative to another sound
Phase
Hearing losses vary in degree, configuration, and type of hearing loss. The audiologist selects hearing aids and adjusts the settings for the individual patient using a _________ ________ .
Prescriptive procedure
____________ microphones have an inherently non-flat frequency response, because of the effect of the long thin probe tube.
Probe
It is important to measure the performance of the hearing aid in an individual patient's ear. This performance can be directly measured using a soft, thin ________ _________ inserted into the ear canal as part of real ear measurements (REM).
Probe tube
A newer form of the BTE hearing aid places the receiver in the ear canal; this form factor is known by the acronyms ________ and/or ________ .
RIC RITE
________________- is measured by placing a probe-tube, connected to a microphone, into the ear canal
Real ear gain
______________ converts the amplified electronic signal into acoustic signal
Receiver
____________ control - handheld device for user control of many functions such as VC, MM, power on/off, directionality, noise reduction
Remote
Impaired physiology in SNHL can include loss of outer hair cell function, loss of inner hair cell function, reduced electrical potential within the cochlea, and changes to the mechanical properties in the cochlea. A result of these deficits is that a person with SNHL needs a greater (more favorable) _________ - _________ - _________ _________ than normal-hearing listeners in order to communicate effectively.
SNR
In a DSP hearing aid, the ________ ________ must be greater than at least twice the highest frequency component present in a complex signal.
Sampling rate
In an earmold, the ________ ________ marks the start of the transition from the cartilaginous canal to the bony canal.
Second bend
________ is the type of material used to manufacture non-allergenic earmolds.
Silicone
A function of the earmold is to couple sound from the hearing aid receiver to the aid wearer's ear canal; this is accomplished via the ________ _______ .
Sound Bore
____________________-The number of decibels by which any sound pressure exceeds the arbitrary, but universally agreed reference sound pressure of 2 x 10 ^ -5
Sound Pressure Level
_____________- A small coil of wire that produces a voltage when an alternating magnetic field flows through it
Tele-coil
Persons with SNHL often show impaired ________ _________ ability. Characteristics of this impairment include (a) reduced ability to separate signals that occur close together in time, [e.g. forward and backward in time] (b) reduced ability to capture snippets of speech information that occur in the presence of a fluctuating background noise [e.g. listening in the gaps], and (c) decreased ability to extract information and cues that are encoded in the temporal fine structure of speech.
Temporal resolution
T/F- With the use of thin tubes for small RITA hearing aids, there is a tradeoff. The pro is that the thin tube is more cosmetically appealing than standard 13 tubing. The con is that the thin tube does not pass high-frequency energy as well as standard 13 tubing
True
T/F-In physics, wavelength x frequency equals the speed of sound.
True
Higher intensity signals (such as amplified first formant of a voiced speech sound or amplified low-frequency background noise) can create problems in the perception of less intense, higher frequency speech cues (such as second and third formants of speech sounds and speech fricatives). This characteristic of cochlear mechanics is known as the ________ _________ _________ _________ '
Upward spread of masking
The _________ ________ amplifier was used in hearing aids from 1920 up until the invention of the transistor.
Vacuum tube
A function of the earmold is to control the extent to which the inner part of the ear canal is open to the air outside the ear canal; this is accomplished via the ________ .
Vent
_____________- Describes how the pressure of a sound wave varies from moment to moment in time
Waveform
_______________-Describes the distance a sound wave travels during one period of the wave
Wavelength
The primary audiology input information to a hearing aid prescription is the ________________
audiogram
The _________ directionality polar pattern has a delay ratio of 0 and has the least sensitivity to sounds from the sides (90 and 270 degrees).
bi-directional
A _________ _________ occurs when hearing aids are worn in both ears.
bilateral fitting
A type of amplification fitting that has a cochlear implant in one ear and a hearing aid in the other ear is a ________ fitting.
bimodal
Bilateral hearing aid fittings can produce a binaural advantage when listing in a complex listing environment. This is because _________ _________ occurs when the brain takes advantage of dichotic signals arriving at the two ears.
binaural squelch
_________ _________ occurs when sounds are presented to (or perceived in) both ears.
binaural stimulation
Real ear measurement (REM) equipment corrects for the response by including a _________ step in the measurement or by applying a correction stored in memory.
calibration
The hearing aid form factor that fits entirely within the ear canal is known as the ________ ________ _________ ________ style.
completely in the canal
The _________ _________ _________ prescriptive approach for fitting hearing aids was created for pediatric applications and utilizes a technique that makes all of the measurements and calculations in dB SPL (e.g. not in dB HL and not in dB Gain).
desired sensation level
What are the first speech sounds lost?
f, sh, th
You can determine the effectiveness of a _____________ reduction algorithm by making measurements, with and without the algorithm engaged, to determine the additional stable gain
feedback
Speech sounds vary in ____________ and _____________
frequency and intensity
For ears with soft texture, _________ earmolds are recommended.
hard
A major problem for individuals with hearing impairment is not having normal sensitivity in both ears and this is most problematic when sounds originate from one side, instead of from the front. When sounds originate from the side, our heads diffract (alter and block) sounds, which produces a significant attenuation of sound on the far side of the head. This effect is referred to as the ________ ________ .
head shadow
The hearing aid form factor that occupies a sufficiently small portion of the cavem concha and its outer surface is parallel to the ear canal opening is referred to as an _______ _______ ________ style.
in the canal
The hearing aid form factor that fills the entire concha as well as about half of the ear canal is the ________ ________ _______ style.
in the ear
The original POGO procedure is a straightforward implementation of half-gain rule, with an additional _________
low cut
In some multi-memory hearing aids, a specialized program can be created for _________ . This non-speech auditory signal is characterized by a wider bandwidth, a wider dynamic range, more variable temporal characteristics, and tonal aspects which a hearing aid may interpret as distortion or feedback.
music
If the slope of the compression segment is _________ , this shows decreased gain associated with increased input level.
negative
The BTE hearing aid and earmold tubing, closed at one end and open at the other end, is a ________________
quarter wave resonator.
Hearing aid microphones are not absolutely quiet as they have ________ ________ ________ ,which can be amplified and sometimes bothersome to persons with zones of normal hearing.
random electrical noise
A dynamic property in a compressor, called the ________ ________ , is the time taken for a compressor to react to a decrease in input level.
release time
A _________ _________ occurs when a hearing aid is worn in one ear.
unilateral fitting
Higher intensity signals (such as amplified first formant of a voiced speech sound or amplified low-frequency background noise) can create problems in the perception of less intense, higher frequency speech cues (such as second and third formants of speech sounds and speech fricatives). This characteristic of cochlear mechanics is known as the ________ _________ _________ _________ '
upward spread of masking
Three types of frequency lowering
1. Transposition 2. Frequency Compression 3. Spectral Envelope Warning
Identify the correct statements with regard to the NAL-NL2 prescriptive fitting algorithm. A. There is an interaction of recommended compression ratio for fast-action compression systems with degree of hearing loss, whereby higher compression ratios (e.g. 3:1) are prescribed for moderate losses and lower compression ratios (e.g. 1.5:1) are prescribed for mild and severe losses. B. There is an age effect and adults are prescribe more gain than children. C. There is a gender effect and females are prescribed more gain than men. D. There is a experience effect and new device users with moderate and severe degrees of hearing loss are prescribed less gain than experienced device users. E. There is a effect of one-ear vs. two-ear amplification and more gain is prescribed for unilateral losses.
A, D, E
The self-report measure ________ has sub-scales of EC, BN, RV, and AV.
APHAB
A test that has been developed to assess the SNR that people need for speech to be acceptable to them is called the _________ _________ _________ test. Values of < 7 dB are a positive predictor of successful hearing aid use and values > 13 are a negative predictor of successful hearing aid use.
Acceptable noise level
Listening to amplified sound (such as through hearing aids) can produce gradual, long-term changes in the hearing abilities of patients. This auditory change is referred to as _________ and may result in adaptation to gain, over time, in hearing aid fittings.
Acclimatization
In a DSP hearing aid, the _______ ________ ________ ________ changes the analogous signal into a numeric representation of the signal.
Analog-to-digital Converter
_________________ Filter- input contains sounds that are above speech frequencies
Anti-aliasing
__________ and _________ - predictive values based on normal hearing processes and speech measures
Articulation Index and Speech Intelligibility Index
Any devices that help hearing-impaired people detect sounds or understand speech, but which are not worn totally on the head or the body are referred to as _________ _________ _________ .
Assistive listening devices
A ________ ________ ________ hearing aid is a two-piece hearing aid system, with the microphone, receiver, and electronics mounted in a characteristic banana-shaped case, from which the sound is conveyed acoustically via a tube into the ear canal.
Behind the ear
One outcome measure may be in the domain of _________, which is defined as the reduction in disability (including both activity limitations and participation restrictions).
Benefits
___________ has one aideable ear and one unaidable ear
BiCros
The _________ era of hearing aid technology spanned from the beginning of the 20th century into the 1940's.
Carbon
The _________ directionality polar pattern has a delay ratio of 1 and the least sensitivity to sounds from behind (180 degrees).
Cardioid
In these directional microphones, the mathematical calculation of the internal delay ÷ external delay produces a numeric value, in the range 0 - 1, for the ________ ________ .
Delay Ratio
The amplifiers in nearly all hearing aids now use ________ ________ ________ , which means that the amplifiers contain circuits to turn the continuous (i.e. analog) electrical signals into numbers, mathematically manipulate the numbers, and turn the new numbers back into analog acoustic signals at the output of the hearing aid.
Digital Signal Processing
In a DSP hearing aid, the _______ _______ ________ converter changes the sample bits into an analog voltage.
Digital-to-analog Converter
Audio signals within the critical distance of a room have improved SNR over signals outside the critical distance. The critical distance occurs when the...
Direct sound field and the diffuse (reverberant) sound field are equal in SPL
The ________ _________ is a value that indicates the ability of the directional microphone to affect the SNR when compared to an omni-directional microphone. This value is a ratio of the frontal sensitivity to average sensitivity from all directions, converted to a dB value in the range 0 to 6.
Directivity index
________________- The amount by which the discomfort threshold exceeds the threshold of audibility
Dynamic Range
To obtain a custom-made hearing aid, the audiologist makes an ________ ________ and sends this to the manufacturer.
Ear impression
_____________- Describes the mixture of pure tones that, when added together, produce a particular complex sound over a specific portion of time
Spectrum
SII stands for _______ ________ ________ .
Speech Intelligibility Index
When the long-term RMS spectrum and dynamic range of the amplified signal in the ear canal is shown superimposed on the patient's thresholds and discomfort levels, all expressed as dB SPL at the eardrum, the result is called a speech-o-gram or ________ ________ .
Speech map
When fitting a mixed hearing loss, the average gain recommended is about one-half of the sensorineuaral loss plus _________ _________ [what fraction or percentage?] of the conductive component (e.g. the air-bone gap)
Three quarters
Microphones and receivers are jointly referred to as ________ because they convert one form of energy into another.
Transducer
The invention of the _________ radically changed the size of hearing aids, in the early 1950's, such that the devices could be head worn.
Transistor
T/F- An approved indication for use for middle ear implants is moderate sensorineural hearing loss.
True
T/F- In the conversion of an audio signal to a digital representation, the greater the number of bits for amplitude resolution, the greater the signal-to-quantization-noise ratio (SQNR)
True
________ is the type of material used to manufacture soft earmolds.
Vinyl
In directional microphones, you want signal to be inside ___________ if it's not then it becomes negative SNR; needs to follow inverse square law
critical distance
Strategic placement of ____________ can reduce or eliminate undesirable peaks in frequency response
damper
With regard to venting a hearing instrument fitting (earmold or earshell), the larger the vent the improved relief from occlusion and ______________ probability for feedback
increased
The greater the hearing loss, the __________ the earmold is needed in the ear and ear canal to stop feedback.
tighter
Compression amplification in hearing aids can be gradually applied (e.g. using low compression ratios instead of high compression ratios) over a wide range of input levels (e.g. a low-intensity knee-point to another high-intensity knee-point). This signal processing approach is known as _________ _________ _________ __________ .
wide dynamic range compression
NAL prescriptions do not recommend 1/2 gain, but instead recommend _________ % gain (with respect to the amount of hearing loss).
46
The NAL algorithms are based on an overall recommendation for amplification that is _____ percent of the hearing threshold level.
46
When evaluating prescriptive fittings for hearing aids, the empirical evidence is that the delivered performance (e.g. the measured amplification) should be within _________ dB of the target values, over the frequency range of 250 Hz to 4000 Hz.
5
While outcomes, using self-report measures, can be assessed at any time after the hearing aid fitting, the extent of benefit does not stabilize until about ________ weeks after fitting.
6
Hearing aid signal processing seeks to classify acoustic signals as either speech or noise. Which of the following items correctly describe the signal processing logic to determine speech or noise? A. LTAS for speech is broadband and LTAS for noise is low-frequency weighted. B. LTAS for speech is low-frequency weighted and for noise is broadband. C. Speech is steady state and noise is modulated D. Speech is modulated and noise is steady state.
A and D
The _________ era of amplification was characterized by sound collection devices such as a hand cupped behind the pinna or an ear trumpet.
Acoustic
________ is the type of material used to manufacture hard earmolds.
Acrylic
__________ ___________ are the difficulties an individual my have hearing in various situations. Examples are situations where the patient hears less clearly than is necessary to function effectively or situations that require so much concentration and listening effort that fatigue quickly follows.
Activity limitations
_________ directionality is the capability of the hearing aid to self-transition among different directionality patterns.
Adaptive
__________________ schemes progressively decrease the gain within each frequency region as the SNR deteriorates
Adaptive noise reduction
As an audiologist, you can determine the effectiveness of a feedback reduction algorithm by making measurements, with and without the algorithm engaged, to determine the _________ _________ __________ .
Additional stable gain
One dynamic property is the the time taken for a compressor to react to an increase in signal level, which is referred to as the ________ _________ .
Attack time
_________ directionality is the capability of the hearing aid to self-transition between omni-directional and a directional mode.
Automatic
Which of the following listening conditions has the lowest directivity index (e.g. the least amount of directionality) in the aided (on-ear) condition? A. ITE - directional B. BTE - omnidirectional C. BTE - directional D. ITE - omnidirectional
B
Adaptive noise reduction (ANR) schemes are characterized by which of the following? A. ANR signal processing requires a dual microphone configuration. B.ANR signal processing routinely improves listening comfort and but rarely improves speech understanding in noise. C.ANR signal processing reduces the gain within frequency regions of poor SNR. D.ANR signal processing relies on the cue of spatial separation of the signal and the noise.
B and C
A bone conduction hearing aid solution for overcoming single-sided deafness is the _________ device.
BAHA
The ____________ is the source of the increased signal power that the hearing aid delivers to the aid wearer
Battery
Bilateral hearing aid fittings can produce a binaural advantage when listening to sounds in a complex listening environment. This is because _________ _________ occurs when the brain combines diotic signals arriving at the two ears.
Binaural redundancy
In radio-frequency transmission of signals for hearing aids, _________ operates at 2.4 GHz (2,400 MHz) and is a short-range (10 m), frequency-hopping, spread-spectrum system.
Bluetooth
The largest type of hearing aid is the ________ aid.
Body
Control of feedback in hearing aids can occur in several ways. The method that has the least detrimental impact on maintaining target gain and output is which of the following? A. Patient turning the VC down when the hearing aid squeals. B. Audiologist programming reduced broadband gain and output to reduce / eliminate feedback. C. Audiologist activating an adaptive notch filter to reduce / eliminate feedback. D. Audiologist programming reduced narrowband gain and output to reduce / eliminate feedback.
C
There are several important auditory cues to localization. These cues may be disturbed with closed mold hearing aid fittings and/or certain signal processing algorithms. Which are the following are important auditory cues to localization in the horizontal plane? A. Inter-aural time differences (ITD) for sounds >= 1500 Hz. B. Inter-aural level differences (ILD) for sounds <= 1500 Hz. C. Inter-aural level differences (ILD) for sounds >= 1500 Hz. D. Inter-aural phase differences (IPD) for sounds <= 700 Hz. E. Inter-aural time differences (ITD) for sounds <= 1500 Hz.
C, D, E
The sequence of smallest to largest, custom, hearing instrument styles is what?
CIC, ITC, HS, ITE
As part of the hearing aid fitting process, one option is to ask the patient to list situations where he or she would like to hear more clearly. At the end of the rehabilitation process, outcomes are assessed for each of these specific situations. A tool, developed by Dr. Dillon at NAL, that uses this approach is known as the ________ .
COSI
An air conduction hearing aid solution for overcoming single-sided deafness is the _________ hearing aid.
CROS
As an audiologist, you can counsel your patients that treatment for single-sided deafness (SSD), with normal hearing in the other ear, includes which of the following device options? BiCROS CROS Middle Ear Implant IROS BAHA
CROS and BAHA
Probe microphones have an inherently non-flat frequency response, because of the effect of the long thin probe tube. Real ear measurement (REM) equipment corrects for the response by including a _________ step in the measurement or by applying a correction stored in memory.
Calibration
People with severe to profound hearing loss are likely to receive more benefit from ________ _________ than from hearing aids.
Cochlear implants
The major role of _________ is to decrease the dynamic range of signals in the environment so that all signals of interest can fit within the restricted dynamic range of the hearing-impaired person.
Compression
One static characteristic is seen in the input/output function, where the ________ ________ describes the change in the amplitude of the input signal compared to the change in amplitude of the output signal.
Compression ratio
The ________ _________ is the level above which the gain of the hearing aid starts reducing as the input level increases. In input/output functions and input/gain functions, this can be identified as the input level at which the slope of the function changes.
Compression threshold
The ________ _________ is defined as the distance from the sound source at which the level of the reverberant sound equals the level of the direct sound.
Critical distance
A primary objective in using wide dynamic range compression amplification is to ... A. Increase the acceptance rate of binaural fittings. B. Maintain the device user's aided dynamic range. C.Compress the device user's aided dynamic range. D. Expand the device user's aided dynamic range. E. Place increased reliance on the user-operated volume control.
D
_________________- prescription is the sensation level in the ear canal, with respect to degree of hearing loss and frequency of hearing loss
DSL
________________ is used for mild hearing loss so you can block out the amplification at certain frequencies
Damper
The _____________ is a flat or contoured sheet of plastic that is trimmed to size and becomes the outer surface of the hearing aid
Faceplate
T/F- An advantage that RITA style hearing aids over RIC style hearing aids is that RITA hearing aids do not have the adverse consequences of thin tube resonances.
False
T/F- Both the Baha and the Ponto come in three power levels: 'standard' for AIR CONDUCTION THRESHOLDS up to 45 dB HL, 'power' for AC thresholds up to 55 dB HL, and 'super power' for AC thresholds up to 65 dB HL.
False
T/F- Hearing aid noise reduction algorithms work by increasing the within-channel gain when the SNR is negative and reducing the within-channel gain when the SNR is positive.
False
T/F- When using the "Count the Dot" audiogram approach, if there are 57 dots that are audible (e.g. below the audiogram threshold contour), that means that the person will be expected to have about 57% speech understanding ability.
False
________________- Mathematical operation that enables the spectrum to be calculated if the waveform is known
Fourier Transform
___________-Describes how many times per second a sound wave alternates from positive pressure to negative pressure and back to the starting value
Frequency
Frequency lowering can sometimes be beneficial in improving audibility of high-frequency cues for a patient with a severe ski-slope hearing loss. Which of the following signal processing methods are utilized in frequency lowering algorithms in hearing aids? Frequency Transposition Frequency Compression Amplitude Lowering Amplitude Compression Frequency Modulation
Frequency Transposition Frequency Compression
When the outer hair cells lose their amplifying ability, the cochlea loses some of its ________ ________ ability, which creates difficulty with SNHL in separating speech sounds and noises that simultaneously occur in adjacent frequency regions.
Frequency selectivity
Lybarger is credited with creating the _________ ________ ________.
Half gain rule
_________________- The amount of gain chose by people was approximately half the amount of threshold loss
Half gain rule
__________ frequencies are less intense than ________ frequencies
High Low
A type of amplification fitting that has a cochlear implant and a hearing aid in the same ear is termed a ________ fitting.
Hybrid
________________- cues are most valuable for high frequencies, above about 1500Hz
ILD
_____________-As frequency increases, this phase cue becomes increasingly ambiguous for sounds that do not have rapid onsets or offsets
IPD
______________-The resulting difference in arrival time at the two ears
ITD
The telecoil in a hearing aid can pick up electromagnetic energy being transmitted in a room via an ________ ________ system.
Induction loop
A _________ amplifier makes everything bigger by multiplying the input signal by a fixed amount.
Linear
___________: amount of gain is independent of input level ; slope of 1:1
Linear
Bilateral hearing aid prescriptions are different than unilateral hearing aid prescriptions, even though the hearing loss(es) may be the same for the two-eared and one-eared fitting. The prescriptive adjustment is because loudness of a sound is greater when it is heard in two ears compared to one ear. This perceptual effect is called binaural ________ _________ .
Loudness summation
____________-Approximately half way between threshold and discomfort, so MCL increases by 0.5dB for every 1dB increase in hearing loss
MCL
A type of compression system has the characteristics of: -output controlled compression -high compression ratio (e.g. > 8:1) -fast attack time (e.g. < 15 msec) -moderate release time (e.g. 20 - 100 msec) -high compression threshold (but low enough to avoid listening discomfort). This type of compressor is use to control ________ ________ .
Maximum Output
Modern hearing aids can communicate ear-to-ear, wirelessly, in order to coordinate ear-to-ear signal processing. The speed of communications and the algorithm adaptations must be faster than the auditory events, as determined in time by the speed of sound. The maximum possible interaural time difference (ITD) between two hearing aids occurs when sounds come from the side (90 degrees) and this time difference between arrival at the two ears is __________ msec.
0.7
The maximum possible interaural time difference (ITD) between two hearing aids occurs when sounds come from the side (90 degrees) and this time difference between arrival at the two ears is __________ msec.
0.7
Normal hearing dynamic ranges go up to _______dB
120
