SAERA - RESEARCH ARTICLE - Effect of Hearing Aid Evolution on Hearing Impaired perceptibility Joseph R. Abdel Nour
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
SAERA - RESEARCH ARTICLE
Effect of Hearing Aid Evolution on Hearing Impaired perceptibility
Joseph R. Abdel Nour
SAERA. School of Advanced Education Research and Accreditation JA Hearing Aid Clinic, Jal El Dib, Lebanon.
ABSTRACT
Hearing aids allow speech understanding in calm atmospheres, but they won't offer significant understandability in
noise. A Major complaint of hearing impaired people is poor speech understanding when noise is displayed in its
different aspects. In the mid of the nineties, the introduction of digital signal processing (DSP) into hearing aids
allowed advanced signal processing algorithms to be executed. After nearly a decade a major share of the hearing
aids became equipped with DSP technology. Giving great progress to speech understanding in noise, more than
half of those hearing aids included directional capabilities with the implementation of directional microphones. The
expansion of open canals has spread vastly since feedback cancellation allowed for the diminution of occlusion
issues. So, the question that comes to the surface, what changed to become successful these days? Technology
advanced sufficiently to enable their application in a usable design; multiband compression may possibly be
implemented in a small frame and with low noise. Directional microphones vastly progressed, and they were
planned to allow exchange between omnidirectional and directional modes to diminish noise issues; feedback
cancellation allowed more noticeable gain in open canal hearing aids, and the acoustics were progressing to expand
the usable capacity and still resides a huge opportunity for digital technology to supply enhancement.
Keywords: hearing aid, hearing instrument, hearing aid amplification, child and hearing aid, frequency compression,
digital noise processing DNP, digital signal processing DSP, binaural communication, hearing aid development,
directionality,
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of Advanced
Education, Research and Accreditation.
1SAERA - RESEARCH ARTICLE
INTRODUCTION
since they include common movements of
existing technology. Radical developments are
It’s a noisy world, and noise proceeds to be a
difficult to anticipate since they include modern
major issue for hearing aid clients. Let’s confront
concepts with no current examples. They too
it, our environment is noisy. Noise is the
frequently lead to troublesome innovations that
moment primary complaint of all taking interest
totally alter the commercial center of an
consumers when eating at restaurants. People
industry.
cannot indeed escape from the noise in their
own homes, as noise is the number-one These sorts of innovation frequently include
neighborhood complaint. Since normal-hearing bringing technology from one field into another,
individuals are subjected to significant amounts and the affect of these recently presented
of noise on a day by day basis, it isn't shocking innovations could be anticipated by those
that the number-one complaint of all hearing learned in both areas. The presentation of
help clients is trouble hearing in noise; nearly Digital Signal Processing ( DSP ) and the
half (49%) of those who return their hearing aids application of feedback cancellation were
supposedly do so since of issues with radical advancements but may have been
background noise, which include the anticipated by those who were mindful of DSP
tirelessness of hearing aid industry use in non hearing aid areas and who were able
technological advancement. to see their potential advantage to hearing aid
clients. In this way, in spite of the fact that
As the level of technology increments, advanced
expectations about the future are often weak,
hearing aids gotten to be more automatic and
expectations of potential benefits from unused
have more features to assist you communicate
technology are not totally ungrounded.
in troublesome listening situations. Modern
Consequently, in spite of the truth that
technologies interpret to higher cost focuses for
expectations about long term are regularly
hearing aids and more noteworthy benefits. The
powerless, the potential benefits from unused
following features are more likely to be
advancement are not totally ungrounded.
advertised in advanced hearing aids. Note that
these sorts of progressed features offers a The question that rises, what are the effects of
totally modern programmed, adaptive and DSP technology as compared to hearing aids
multiband plan, they are special to hearing aids, without DSP on audibility outcomes, speech
they are planned to upgrade speech, decrease recognition outcomes, speech and language
noise and optimize the control of it all through outcomes (Q1) and what are the effects of
management of directionality, noise reduction directional microphone response as compared
and locks in them both to facilitate and work to omnidirectional response on audibility
better. outcomes, speech recognition outcomes,
speech and language outcomes (Q2).
Industry developments happen in incremental
steps or in radical changes. The incremental
developments are less demanding to anticipate
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of Advanced
Education, Research and Accreditation.
2SAERA - RESEARCH ARTICLE
MATERIAL AND METHODS A list of discipline specific data extraction points
was developed summarizing the critical features
of each study, including study design,
Literature search characteristics of the population, previous
The articles for this review have been taken hearing aid usage, test hearing aid features,
from a literature search of hearing aid hearing aid settings (including volume control
processing features. PubMed and Google and equalization), study protocol, outcome
scholar databases were searched utilizing measures, findings, and limitations. summaries
keywords related to hearing loss, children, and were reviewed for accuracy and completeness.
amplification (i.e., hearing aid, hearing Studies selection
instrument, amplification, child and hearing aid,
frequency compression, digital noise processing The primary search produced 37 studies. After
DNP, DSP, binaural communication, hearing aid checking them using the keywords hearing aid,
development, directionality). Reference records hearing instrument, hearing aid amplification,
were carefully inspected, they were retrieved child and hearing aid, frequency compression,
from the introductory search to distinguish DNP, DSP, binaural communication, hearing aid
extra significant articles. McCreery was a lot of development, directionality; 10 articles with
help when citing the studies acknowledged for content relevant to the research questions were
incorporation (McCreery et al., 2012). extracted. The strategies commonly used in
those articles were categorized into behavioural
Study was based on the following consideration: and a bit physiological evaluation of listening
a) Quasi experimental research plans. effort. The reference records of these studies
were inspected, and a final look was upgraded.
b) Studies written in English. This brought about 9 articles in the last total
being chosen for the review.
c) Studies counting all ages with reported
conductive, mixed, or sensorineural hearing Of the 37 studies recognized, 6 were eliminated
loss. amid the quick review of the abstract and an
extra 7 were avoided after review of the total
d) Studies utilizing wearable hearing aids that
text which was short, incomplete and weak. Of
are currently accessible in hearing aid market.
the 24 remaining studies, 14 were eliminated
Operational definitions of signal processing after further examination because they lead
techniques and results are included in McCreery elsewhere in their discussion of which I took
et al., (2012). Inclusion criteria was applied to some hints for the present and prepared the
decide study eligibility based on abstract. Full formal first paper. Reasons for avoidance were
text versions of each included study were that the study did not specifically address a
independently reviewed at least twice by question for this or another review within the
experienced authors (i.e., Venediktov & Wang, series, did not give sufficient data for
2011). These authors appraised experimental investigations, or detailed the use of technology
research for quality. The scheme was adapted not anymore available in commercial hearing
for evaluation of within subject repeated aids. See McCreery et al. (2012) for a chart
measures designs with special consideration for portraying this process. All this happened after
threats to internal validity arising from these removal of a duplicate of the same text. This
study designs (Portney & Watkins, 2009). process brought out in a total of 10 articles, nine
of which are included in this review. So, ten
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
3SAERA - RESEARCH ARTICLE
studies from nine articles were included in this that school age children can reliably change
review. their hearing aid program in response to
changes in the environment (Scollie, 2010), but
For each study, the data relating to the hearing the efficacy and effectiveness of adaptive signal
aid evolution, comparison, outcomes, study processing features have yet to be determined.
design criteria and the measurable results
relating to both questions (Q1 and Q2) were Adults can experience improved ease of
extracted. Proof relating to Q1 was given by 5 listening in noise with DSP compared to
studies. Prove relating to Q2 was given by 4 conditions without DSP (Boymans & Dreschler,
studies. Using the experimental work on hearing 2000; Ricketts & Hornsby, 2005). For example,
impairment or hearing aid technologies and Mueller, Weber, and Hornsby (2006)
listening effort or fatigue during speech documented that while DSP did not change
perception, this fulfilled the hearing aid user speech recognition for adults, DSP did result in
benefit in first place, the proper intervention, listeners being able to tolerate a higher
control, outcomes, and study design selection acceptable noise level in comparison to
criteria. conditions without DSP. The lack of
improvement or degradation in speech
SIGNAL VARIABLE PROCESSING understanding for adults with DSP is not
surprising given that most algorithms use
modulation detection to reduce gain only for
Directional microphones and digital signal periods of the signal where only noise is present
processing (DSP) are hearing aid features that (Kates, 2008). Some DSP algorithms may
were developed to minimize the negative selectively reduce gain only in frequency regions
effects of background noise for hearing aid where noise is the primary signal; however, the
users. DSP includes a wide range of signal spectral characteristics of speech and noise in
processing strategies designed to classify the realistic environments often overlap
input to the hearing aid as primarily speech significantly. Therefore, when both speech and
input or noise input, and then reduce gain when noise are present in the environment, many DSP
the input to the hearing aid is predominantly algorithms do not make significant changes to
noise. DSP can be implemented using a wide the signal in order to preserve the audibility of
range of algorithms, including modulation speech (Peeters, Kuk, Lau, & Keenan, 2009).
detection and complex filtering. Significant Even if DSP were active when both speech and
differences in the implementation of DSP noise were present in the environment, any
between manufacturers and within reduction in gain would be applied to the
manufacturers’ different products make general combined speech in noise signal, making it
predictions about the effect of DSP and related unlikely that SNR improvements would be
outcomes difficult (Hoetink, Körössy, & sufficient to improve speech understanding.
Dreschler, 2009). Therefore, as with adults, the primary objective
The evolution of programmable directional for using DSP with children should be to
microphone and DSP settings, as well as maintain speech understanding while limiting
adaptive features that change automatically in the negative impact of background noise on
response to the environment, create new listening effort, cognitive processing, and the
challenges for clinicians who must decide child’s listening comfort. In cases where DSP
whether these features should be activated as does result in decreased speech audibility, the
well as how to verify any impact their use may negative effect on speech recognition would
have on audibility. Recent data support the idea likely be greater for children than what would be
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
4SAERA - RESEARCH ARTICLE
expected with adults, as children require more children than those previously reported with
audibility to reach the same levels of speech adult listeners.
recognition as adults (Stelmachowicz et al.,
2001). In consideration of the population, intervention,
comparison and outcome. Our population of
Unlike DSP, directional microphones have the interest is school age children, and our
potential to improve the SNR for the listener, intervention comparisons include the use of DSP
particularly in situations where the signal of in hearing aids versus the use of hearing aids
interest and noise sources are spatially without DSP and omnidirectional response as
separated (Boymans & Dreschler, 2000; Gravel, compared to directional microphone response.
Fausel, Liskow, & Chobot, 1999). The benefits of Four categories of outcome measures have
directional microphones for improving speech been suggested to evaluate the efficacy of
understanding in noise for adults who use hearing aid features with children: audibility,
hearing aids have been previously documented speech recognition, speech and language
in three systematic reviews (Agence outcomes, and subjective measures (Hogan,
d’évaluation des technologies et des modes 2007). Audibility, the ability to hear sounds
d’intervention en santé (AETMIS), 2003; Amlani, directly, impacts an individual’s ability to
2001; Bentler, 2005). Whereas the magnitude of recognize, learn, and interpret speech.
improvement observed with directional Audibility outcome measures are objective
microphones varied across studies, reviews by measures of speech audibility, including sound-
AETMIS (2003), Amlani (2001) and Bentler field testing, real ear measures (gold standard),
(2005) all reported that overall directional real ear coupler difference, Articulation Index
microphones did provide a statistically (AI; ANSI S3.5-1969) scores, and Speech
significant improvement in speech recognition Intelligibility Index (SII; ANSI S3.5-1997) scores.
across studies with adults. In general, the largest Because children with hearing impairments are
improvements in speech recognition were more likely to have limited exposure to audible
observed for experimental conditions where the speech (Arlinger, 2001), they are at increased
stimuli are presented in front of the listener and risk for language difficulty in areas such as
the noise source was fixed behind the listener. vocabulary acquisition which is important in
The presence of reverberation, diffuse noise developing context for academic subject areas
sources, or other more realistic acoustic (Maynard, Pullen, & Coyne, 2010; Myers &
conditions resulted in smaller improvements in Botting, 2008; Scarborough, 1998). Speech
speech recognition in adults. recognition outcome measures are objective
measures of speech stimuli identification,
Although existing studies can provide clinicians including phoneme, word, and sentence
with support for using these advanced HA signal materials. The accurate perception of speech
processing strategies with adults, the findings underlies the development of spoken and
are difficult to generalize to children in school written language skills (Bavin, Grayden, Scott, &
age populations due to the ongoing Stefanakis, 2010; DesJardin, Ambrose, Martinez,
development of auditory, speech, and language & Eisenberg, 2009). Speech and language
skills coupled with the unique, acoustically outcome measures include standardized
complex environments in which they must measures of communication development.
access auditory information. Changes in Ultimately, the impact of hearing ability on
audibility that result from DSP and directional social interaction becomes a primary focus and
microphones may have different effects on is often captured by self-report or parent report
questionnaires. The impact of these outcomes
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
5SAERA - RESEARCH ARTICLE
on school age children fitted with hearing perceptibility of soft sounds, however keep loud
devices is an important consideration for sounds comfortable. In any case, as expressed
audiologists who provide services to that prior, hearing help advantage still changes for
population. hearing impaired patients, particularly in noise.
Speech Processing Effect of DSP on auditory resolution abilities
Through observations from clinical encounter, Few individuals would have anticipated such
hearing care experts know that two patients progresses within the hearing aid industry at the
with about identical audiograms can change starting of the 1990s. Few would have indeed
within the advantage they get from thought at that time that multiband wide
amplification. Whereas both may report great dynamic range compression (WDRC) would get
advantage listening in calm, they may vary in to be the standard processing for hearing
their ability to get it in noise. disability; a noteworthy number of analysts had
been distributing at the starting prior to 1990
Older listeners often report increased difficulty that shown WDRC was pointless and maybe
hearing in noise than younger listeners. inconvenient. Directional microphones had
Temporal auditory processing abilities have been attempted in hearing aids, as had noise
been found to decline with age, even in the decrease and even open-canal fittings by 1990,
absence of hearing loss (Fullgrabe, 2013). This none with much victory. Without all that,
could complicate the interpretation of the nothing would have led to the actual
factors that affect auditory processing. An advancement of hearing help businesses.
interaction between hearing loss and cognition
has also been established specifically, compared Inevitably, DSP has come to a state of
to hearing impaired listeners with intact development inside the hearing aid industry.
cognitive ability. This suggests that more central Most hearing aids have a comparable set of DSP
neural processes may be involved in patients algorithms that incorporates multiband
presenting with poorer cognitive function. compression, noise decrease, feedback
cancellation, directional processing, and
The relevance of these factors alone or environment classification. Various thought-
combined along with other influences like
leaders inside the industry have suggested that
memory, attention and motivation, is to
DSP progression chip has outpaced the
emphasize that auditory processing relies on industry's thoughts for its application (i.e., that
information flowing upstream and downstream, DSP chips in hearing aids presently have more
from the afferent and efferent neural pathways capabilities than companies know what to do
between the ear and brain (Tremblay and Miller, with) which we ought to not anticipate much
2014). When the integrity of the peripheral or future progression in DSP convenience. In truth,
higher auditory system breaks down, temporal the reverse is a fact.
fine structure information becomes susceptible
to the adverse effects of a damaged system. Each major hearing aid company spends a
significant effort squeezing the signal processing
Hearing aids and individual performance that they need to supply into the limited
variability capabilities of hearing aid DSPs. In doing so, they
No one will contradict the idea that hearing aids regularly rearrange the algorithms, making
are the leading remedy for hearing loss. Mostly them less complex than the build initially
enhancement strategies employ wide dynamic arranged, in order for the algorithm code to fit
range compression (WDRC) to extend the inside the limited clock cycles and memory of
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
6SAERA - RESEARCH ARTICLE
the DSP chip. This is often to some degree capabilities become advanced and as we learn
associated to scaling back the design on a more about the advantage that current
computer game since the video card or central algorithms give taking in consideration for
processing unit isn't powerful enough to handle instance noise reduction. The
all of the 3-dimensional features that the telecommunications industry gives an
software might provide the fundamental illustration of how noise decrease and speech
usefulness is there, but the involvement isn't enhancement can be progressed in hearing aids;
about as great because it might be in case the cell phones have significantly more modern
hardware was more powerful. noise reduction algorithms based on their
effective DSP chips. While current hearing aid
For the purpose of keeping their drainage equal noise reduction algorithms depend on envelope
to a fraction of a milliampere, DSP chips in measurements and basic environment
hearing aids run their clock speeds at just some classifiers to operate, more advanced
MHz, contradicting general purpose DSPs algorithms in other areas use speech production
utilized in customer hardware game devices models within the shape of linear predictive
that can run at hundreds and thousands of MHz. coding and filtering as a portion of their speech
The programming and data memory in hearing detection and noise reduction systems.
aid DSPs are too limited to a number of tens of Although these algorithms don't increment
kilobytes of random-access memory (RAM), speech understanding relatively to the
instead of Gigabytes of RAM in the hardware of
unprocessed signal, they might offer improved
everyday use DSPs. Algorithms right now found
sound quality over current hearing aid noise
in hearing aids have been streamlined so that reduction.
they all can run on a single DSP chip and fit in its
memory. These DSP chip limitations weaken As soon as the speed and memory of hearing aid
moreover the introduction of familiar processors increase, more advanced shapes of
applications, features or algorithms that can run new hearing aid algorithms will be made by
on more capable commercial DSPs. These hearing aid companies. They will use every
realities mean 2 things for the future: support they can get, either through internal
advancement or interpretation when
1- Current hearing aid algorithms will progress motivating universities students and other
over time as hearing aid DSP chips turn to research centers, giving additional advantage to
become more powerful. the hearing aid wearer.
2- Algorithms not in use actually within the
Modern professional algorithms will be
hearing aid industry will be launched when presented as DSP microchips advanced in
hearing aid DSP chips can become enough capability. A number of these unused algorithms
performing when running them. The restriction will moreover be borrowed from other
with what hearing aids can do dwells within the companies experienced in sound business
chip innovation, not within the knowledge of knowing that they have had numerous years
what can be done with them. If that is the case, with audio chips business to gain this expertise
then what DSP algorithm developments can we and offer capable chips to create and optimize
expect within the future? their processing plans. For instance, let us look
New algorithms and their improvement at the music recording industry; it has offered
quite advanced sound handling algorithms for
Algorithms that right now exist in hearing aids compression, pitch shifting, and other effects
will be progressed and refined as DSP that have been optimized by exceedingly
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
7SAERA - RESEARCH ARTICLE
enthusiastic listeners. Most of these algorithms hearing aid may encounter. Rather though,
from other businesses, in any case, will require hearing aid wearers return their since they can't
significant work to adjust them for hearing aid tolerate noise but cell phones client will not.
utilization. There are a few reasons for this.
Last, algorithms in other fields were planned for
To begin with, as it has been expressed, hearing everyday normal hearing users. How they
aids continuously have less effective DSP would need to be adjusted for use by those with
capabilities than other industries. They don't hearing impairment is not clear in case this was
have the same dimension and power problems. achieved. Wider sound related channels,
This implies that a lot of work will still exist to loudness recruitment and changes to forward
rearrange algorithms and coordinate them with masking capacities might cause hearing
existing hearing aids. Furthermore, hearing aid impaired listeners prefer distinctive processing
DSP chips utilize a 16-bit fixed point plans than those optimized for regularly hearing
representation of data, while numerous other audience users. The interaction of modern
sound devices utilize 32-bit floating point algorithms with other hearing aid algorithms
representations. Handling 16-bit signals such as multiband compression will moreover
requires less control but can moreover be more need to be carefully explored to guarantee that
vulnerable to not perform mistakes and algorithms work together smoothly.
dynamic range issues, so switching 32-bit code
to 16-bit code whereas offering negligible WIRELESS TECHNOLOGY
computational mistakes can be a time-
consuming job.
In a couple of decades back, digital
Rather, most sound businesses have signal processing revolutionized the hearing aid
exceptionally particular work on the unique industry and brought an evolution in modern
sorts of sound that they prepare. The applications that provided a modern advantage
telecommunications industry ordinarily forms to the hearing impaired. Sometime before its
speech at high signal to noise ratios; the music introduction, the conceivable good thing about
industry forms as it were voice and musical digital technology to hearing aids was not well
instruments, frequently isolated into individual interpreted, and numerous studies were
tracks; the video chat industry forms as it were conducted comparing digital hearing aids with
sounds that exist in conference rooms, such as analog hearing aids to decide whether digital
speech and air conditioning noise. technology was giving an advantage. Nowadays,
the advantage of DSP is clearly due to its
On the other hand, hearing devices have to
capability to execute algorithms (i.e., feedback
tolerate and handle all probabilities of sound
cancellation, noise reduction, environment
combinations a user may be exposed to, in
classification, and data logging) that could not
different ways of living with all the possibilities
be executed with low power. What is
of subtle distortion for someone listening all day
additionally clear is that utilizing DSP in a
long through these aids. This means, they have
hearing aid was a revolution that changed the
to be able to handle each sound whereas it is
hearing aid business field in unexpected ways.
interpreted as a signal or noise in all possible
Individuals have presently begun to ask what is
combinations. Algorithms that are costumed to
next, what improvement could come to the
work as headsets in an office cannot basically be
hearing aid business. I guess the answer now is
used as a hearing aid algorithm without
present in wireless technology which offered in
achieving some serious change to guarantee
that they work properly in any condition a
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
8SAERA - RESEARCH ARTICLE
2016 a new revolution to the hearing aid when the recipient is far from the transmitter.
industry. Digital signals maintain their signal constantly
with more prominent consistency. The quality
Primitive wireless in hearing aid world remains great up to a certain noticeable
Wireless technology has existed within the distance, which once passed the quality drops
hearing aid business for many years in the shape significantly. This gets to be the convenience
of analog systems. These systems usually distance, in which users that the sound they
comprise a transmitter that is connected to a listen will be uncorrupted by distortion and
sound source, such as a lecturer's microphone noise. This capability of digital wireless is due to
or an audio/ video system, and a recipient that mistake correction coding, a method that
is connected to the hearing aid to get the identifies when mistakes happen within the
wirelessly transmitted signal. Cases of these wireless data and rectifies them. Digital coding
systems are a microphone on an instructor that systems are moreover safer to interference than
transmits an FM signal through a direct electromagnetic signals.
connection on a behind the ear (BTE) hearing aid A massive number of companies working in
or a loop plugged into a lecturer's microphone wireless technology try their best to advance in
in a theater whose electromagnetic signal is the wireless technology and drive down cost
gotten by a telecoil inside of a hearing aid. and size than their analog counterparts which
Worldwide, nor the FM systems neither loop results in a great benefit in its application to the
systems have accomplished a victory outside of hearing aid industry.
specified uses like the flagrant example, Future of wireless technology
classroom. They were limited by the following:
Nowadays hearing aids can connect to certain
1- The stigma of instrument visibility. limited audio items like the land phone or
2- FM systems were very expensive. television with the assistance of special
interfaces manufactured by the hearing aid
3- Users have to use accessories installed industry. In the future hearing aid will be
in a wireless system. wirelessly connected to a wider range of sound
4- Accessories should always be carried systems. This will be possible since digital
around by the hearing aid user and they had to wireless technology is getting to be present in
take their time to wear them on and off. customer electronics. An expanding number of
items are being delivered with remote
5- The different branded systems capabilities. More vitally, sound items that
incompatibility. hearing aid wearers need to listen to are being
made with digital wireless technology implanted
6- The lack of liability of electromagnetic
within the item, making them simpler to
transmittance.
connect to hearing aids wirelessly. In case a
On the other hand, the digital wireless television is transmitting its sound wirelessly, at
technology comes to improve and change all that point a wireless recipient can be included to
these limitations and add more functionality the television so that the hearing aid wearer can
with better results for hearing aid users. listen to sound easily; very similar to what is
happening with mobile phones and without the
Digital wireless systems have a signal with high help of an outside device that needs to be
fidelity than do analog systems. With a wireless connected through the connection plugs.
analog system, the signal quality diminishes
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
9SAERA - RESEARCH ARTICLE
All of these wireless improvements would still making Bluetooth accessories that connect into
not make connecting hearing aids simpler for a behind the ear hearing aid. They give
impaired users in case each device transmitted connectivity between hearing aids and cell
sound with a different connectivity method. phones such that the cell phone sound is
Bluetooth, in any case, has ended up a standard transmitted specifically straightforward to the
that manufacturers have agreed to utilize when hearing aid. An additive is sometimes is present
they digitally transmit their audio signal. This depending on the version of software used,
permits other items with a Bluetooth recipient where the wearer can pick up a signal from the
to choose up the transmitted sound and play it microphone of the mobile phone when
without any specialized design requirements. A someone speaks through. These features
single Bluetooth recipient in or connected to a basically change over the hearing aid into a
hearing aid can get sound from all sorts of sound hands-free cell phone earpiece where the
sources like televisions, radios, cell phones, MP3 hearing aid wearer's companion can moreover
players. The use of Bluetooth for open permit the transmission of his voice specifically
broadcast systems has moreover been into the hearing aid. With this innovation, the
suggested to be embedded in different devices. signal to noise ratio is pretty well enhanced
Here are some features you may be able to use better than the technology given by a
with your hearing aids through your mobile directional microphone on a hearing aid or a
phone with the help of Bluetooth: microphone worn by a companion to transmit
his sound. As hearing aids ended up wirelessly
- Stream phone calls directly to your
associated with a number of accessories over
hearing aids. the following few years, control of the
- Stream audio, such as music or driving connection will become a vital issue.
directions, directly to your hearing aids. This use of wireless connectivity is the beginning
- Change left and right volume together of modern benefits. The Bluetooth protocol
or separately gives connectivity audio sound and adds to it,
non audio data such as control signals. When
- Switch between the programs or Bluetooth is utilized to tune in to a cell phone,
memories set by your provider the wireless digital signal passes the sound back
- Find lost hearing aids and forward between the phone and the
earpiece. It additionally transmits commands
- Check battery status such as volume control, answer, mute, and hang
up. This capability will permit hearing aids to
- Control hearing aid accessories like a TV
control other items with customer use of the
streamer or remote microphone
hearing aid.
Knowing that it will not last long before direct
Within the customer accessories use, wires that
streaming between hearing aids and other
are utilized to transmit information and control
accessories will take place without the
signals between items will inevitably be
intermediacy of mobile phones. Take for
switched by wireless technology like
example car sound systems, they still need to be
transmitting pictures from an advanced camera
connected through the mobile phone but will
to a laptop or transmitting sound from a DVD
not last long before they can get connected
player to speakers. Bluetooth is utilized to
directly to hearing aids without any mentioned
replace programming cables used to program
interference. Hence, as mentioned
hearing aids, and new applications will be
previously, hearing aid companies are presently
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
10SAERA - RESEARCH ARTICLE
created to give developed benefits to hearing As the wireless connectivity speed increments,
aid wearers and audiologists. the space of functionality usefulness will
become greater. Inevitably, a pair of hearing
In the description of the future of hearing aids, aids will function as one instead of 2
where all sound sources communicate with independent hearing aids. With binaural
wirelessly, and propose that text to speech can communication, each function inside the
be utilized in hearing aids to transfer mail hearing aids can end up synchronized. Handling
directly to them. Clearly, the connection may moreover be shared between the aids to
between the hearing aid and numerous devices overcome DSP chip limits, where algorithms are
will be the standard. Numerous more computed as it were one hearing aid and the
possibilities for interaction between hearing results are shared with the other instead of
aids and sound products or probably non audio calculating the algorithm in both hearing aids
products are possible. independently. With this approach,
A coming generation of hearing aid that is computations are shared between the aids,
equipped with a miniaturized camera is being overcoming computational limits on the hearing
created at the College of Stirling in Scotland aid chip. The disadvantage of this, of course,
where a research group driven by a computer would be that the 2 hearing aids are dependent
researcher, Amir Hussain. Ph.D., is inventing a on each other and don't function as they should
hearing aid to assist clients in noisy atmosphere, when the other is missing.
it can lip read and handle visual data in genuine When data rates for binaural hearing aid
time. According to a College of Stirling this communication increase enough to pass audio
project has a probability to improve the lives of between them requiring a rate of hundreds of
millions of hearing aid users. thousands of bits per second, speech
In fact, existing hearing aid companies are understanding in noise can be improved using
working on audio basis only, but the next hearing aid communication to improve
coming technology of audio-visual hearing aids directionality management to overcome the
will interpret the speaker’s face for the purpose head shadow effect. When data rate increases
of lip reading. These will help enhance the audio with binaural communication, the probability of
sounds that are normally processed by transmitting data from a hearing aid to another
conventional hearing aids. will allow processing sound similarly to the
CROS/ BICROS system added to it the
Binaural communication with bilateral hearing directionality of course.
aids
In fact, speech understanding in noise can be
Binaural hearing aid communication describes progressed utilizing beamforming methods. At
the situation where the left and right hearing its most fundamental level, the signal from both
aids of a bilaterally fit wearer communicate hearing aids can be merged together to enhance
wirelessly with each other. This functionality has the signal to noise ratio for a target signal
been recently introduced into the industry, but targeted by the hearing aids simultaneously.
still though at the low data rate of bits per
second. Current applications for this Progressed binaural communication will end up
communication are synchronization of left and an industry when it gets to be developed
right volume controls and management of targeting enhanced perception for the purpose
amplitude of the non listening ear and a few of increasing results in speech discrimination.
other basic functions. Till now, small is known about the effect of
hearing aids on such binaural phenomena as
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
11SAERA - RESEARCH ARTICLE
localization and spatial release from masking, environments. For those who have greater
but binaural communication might give a losses with SNR, directionality can still help with
mechanism for addressing any interactions speech understanding as long as text cues are
between hearing aids and binaural perception available.
by attempting to protect binaural signals with
processing synchronization between the ears. Directionality has evolved in a way that can be
described in a step by step process where more
Disadvantage of digital wireless communication complex algorithms have been sequenced over
time. The center here will be on how each
Until now, power consumption limits the improvement varies from fixed directionality to
presence of digital wireless technology in each newer technologies improving the SNR for
hearing aid. In general, a Bluetooth chip requires hearing aid users by attenuating sound from
nearly 30 mW to transmit and get sound. some directions while emphasizing it from
Usually, most hearing aids require less than 1 others.
mw of power, so including a Bluetooth chip
would increment the power consumption Beginning of directionality
drastically and decrease the battery life of the
hearing aid. Until this power issue is solved, Rather though hearing aids with directionality
Bluetooth chips will not likely be included as a were accessible recently in the 2000s, they had
component inside a hearing aid. higher capacity to switch between
omnidirectional and directional. These aids
As digital wireless chips proceed to be designed represented the primary step within of today's
smaller and lower in power, these limitations advanced directionality, and the advancements
will vanish, gradually and it is likely that all of the eventually gave generally end user advantage
hearing aids will have wireless technology and led to the acceptance of directionality as a
implanted in them within the same way that all critical feature in hearing aids. In fact, buyers
of the hearing aids nowadays have DSPs. When focused higher on directional hearing aids
this happens, hearing aids will all contain compared with omnidirectional ones.
binaural communication and will be associated
to nearly any sound source that the wearer Measured in real life atmosphere, directional
hearing aids improve the signal to noise ratio
needs to listen to. The engineering challenge will
arriving from the front around 3 dB. This SNR
be to form interfacing to these sources as simple
as possible for the hearing aid wearer. advancement can be higher when most noise is
to the rear of the listener. Directionality is
effective when the signal is in front of the
DIRECTIONALITY
listener and within 3 meters. Beyond this
distance, directional microphones do not
Over the final 2 decades, numerous directional provide significant benefits. Knowing that
features have been presented in digital hearing directive hearing aids work better when noise is
aids of which adaptive directionality. These coming from a different direction of the signal
features got to be well clarified especially for the with the inconvenience that hearing aid user
hearing aid users so they can be utilized suitably. must consider the sound he wants to hear and
Listeners with increased hearing difficulty in position himself straight accordingly.
noise or low scores of SNR and with mild to
Switching
moderate hearing loss can get the outermost
benefit of the directional microphone when Hearing aids with directionality had a
using their hearing aids in different noisy partitioned memory for the directional feature,
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
12SAERA - RESEARCH ARTICLE
and clients had to switch to this program when might need to reposition themselves towards
they find themselves situated in a noisy the source of sound in order to attain the
environment to get benefit from the use of directional position in a noisy place.
directionality but a quite good proportion of
clients did not switch between the settings and Adaptive directionality
frequently did not know when to switch and/or The following step in directionality
did not need to do this manual switching. advancement was the presentation of adaptive
To solve this issue, automatic switching hearing directionality. This kind of directionality works in
aids were presented where the hearing aid a way that the open stream of directed angle
automatically changes from an omnidirectional can be directed to the point where the foremost
setting to a directional setting depending on the source of sound is identified in the environment,
environment. These sorts of switching thus adapting the weakening to the noise
algorithms depend on classification systems attenuation. This may indeed be done at
inside the hearing aids, which analyze the distinctive frequencies such that a hearing aid
acoustic scene and make a choice approximately might have diverse directionalities depending
which mode would be most useful. on the frequency and area of the noise.
In this way, these systems are restricted by the Nowadays many hearing aids come with
precision of the specified frame and do not have adaptive directionality. The good thing about
to decide the hearing aid user’s intention in this sort of directionality is that, when a user is
complex listening circumstances. Assuming that in an environment where most of the noise is
the hearing aid user must direct himself towards coming from a specific area, the hearing aid can
the source of sound he wishes to listen to. put the point of most extreme attenuation at
this area making a bigger SNR change. In
Knowing that automatic switching can be circumstances where noise is more diffuse (i.e.,
helpful but unfortunately, the hearing aids don't a cocktail party or reverberant environment),
continuously switch to directionality when the hearing aid adjusts to a certain previously
required. For this reason, a memory with set program.
continuous directionality activated is supportive
for some users whom they are willing to use Adaptive directionality pros and cons:
manual switching. They should be informed 1) Adaptive directionality can be more
that, in case they are having trouble in noise useful to hearing aid users in certain situations.
with auto switching, they can switch to the full These situations include those in which the most
time directional program to see if it gives a important noise source is present at one
change. particular location like the noise source on the
When hearing aids are in directional settings, left side of the hearing aid user. In this case, the
users can not hear clearly present sounds to adaptive directional design will steer the
their sides and back; in this way, they are streaming angle towards the source of sound
restricted to hearing what is coming from the giving the maximum directivity. The only time
front of them. Since the hearing aid user might this would break even with a fixed directional
not continuously need to listen to what is in setting would be when the null happens to be at
front, automatic switching like this may be this same angle.
annoying. Once more, patients got to be 2) When noise is more diffuse within the
informed that the sound they need to hear environment, adaptive directionality gives
should be in front of them. Meaning that, they
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
13SAERA - RESEARCH ARTICLE
nearly the same performance as fixed It's viably important to understand that
directionality. asymmetrical directionality is one hearing aid is
set to directional mode and the other is set to
3) Adaptive directionality could be a great an omnidirectional mode which gives the same
choice since it can both provide fixed SNR benefit as utilizing two hearing aids that are
directionality and automatically adjust when set within the directional settings. A few studies
noise isn't diffuse. have confirmed this.
4) In the hearing aid industry, many Knowing that setting two hearing aids
hearing aid companies utilize adaptive asymmetrically without a specific manufacturer
directionality as their default settings in setting might give the hearing aid user the
common with automatic switching; this is set as annoying feeling of being unbalanced hearing.
a default primary program in hearing aids that Algorithms specifically designed for asymmetric
offers a lot of advantages for the hearing user in listening use band-split directionality for a more
noisy environments. balanced listening experience.
Angle adjustment of an open stream Advancements in directional technology have
Another advancement along the developmental progressed vastly helping hearing aid users in
process of directionality is width adjustment noisy atmospheres. These advancements have
where the stream angle can be narrowed or brought better sound quality and way better
broadened depending on the signal level. directionality than what was presented within
Particularly, the hearing aid screens the levels of the early 2000s. It isn’t sufficient to fit hearing
the sounds entering and changes the width of aids with directionality. A clinician must get the
the directional stream. The stronger the signal benefits and of the numerous settings
coming, the narrower become the stream accessible nowadays. Suitable programming
width. This moreover can be adjusted physically and counseling will position the hearing aid user
in some instruments where the width can be set for understanding in noise knowing that as a
to a wider or smaller angle. matter of fact this is not applicable in all cases
especially with severe cases of bad speech
Asymmetric directional fittings discrimination.
Another way to utilize directionality is to keep
RESULTS
one hearing aid set to omnidirectional and the
DSP
other set to directional. This apparently unusual
way to apply directionality can give a stronger Proof relating to Q1comparing hearing aid
listening atmosphere for users of hearing aids results with and without DSP, given by 5 studies.
and overcome the restrictions of directionality They mainly provided speech recognition
examined above. Specifically, an asymmetric outcomes when testing hearing aids on
fitting can overcome the need of utilizing participants exclusively with moderate hearing
manual systems and the dependence on more loss. Participants are divided according to their
standard systems. An extra advantage is that it age into two groups, group A mainly formed by
does not cut a listener off from their children ranging between 7 and 15 years old and
environment as wearing two hearing aids in group B mainly formed by adults ranging
directional settings can do. The user can choose between 53 and 60 years old.
to listen to any sound they want to listen to.
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
14SAERA - RESEARCH ARTICLE
Five different utilized hearing aid models with experienced users then fitted similarly between
varying DSP algorithms were identified across one and three months with DSP hearing aids.
the five studies that included SONIC Captivate
60 MNR, Bernafon Viron 5 MNR, Oticon Open S - Experienced bilateral fitted sensorineural
MNR, Widex Moment RIC 312 D and Phonak hearing loss with/ without DSP. Group (B, α)
Naida B tried between 1 and 3 months after - Non experienced bilateral fitted sensorineural
using a mix of old analogic hearing aids for hearing loss with/ without DSP. Group (B, β)
comparison purposes. Outcomes were self
provided or through taking parent or relative Where Group (B, β) could be used as control
report. Speech discrimination scores consisted group, since it is formed by first time hearing aid
of nonsense syllable and word recognition users.
tested at varying levels between +40 to +60dBs. Effect of relief DSP (±100%) nDSP=±1
The dependant variable was named the ‘The - Group (B, α), n1 = 0.02 [-0.49, 0.51] => n1=2%
effect of relief with DSP’ (nDSP). It is measured
in percentage (%) and varied between negative - Group (B, β), n2 = 0.18 [-0.41, 0.59] => n2=18%
and positive values.
As a total of group B: nB = (n1+n2)/2 nB =
In fact, 3 different results were obtained with (2+18)/2=10%
group A:
Final Effect relief combined by children and
- Experienced bilateral sensorineural hearing aid adults becomes:
user with/ without DSP. Group (A, α)
nDSP= (nA+nB)/ 2= (17.33+10)/ 2= 13.665% =>
-Non experienced bilateral sensorineural nDSP~0.137
hearing aid user with/ without DSP. Group (A, β)
Table 1. Outcome of nDSP
- Experienced bilateral conductive hearing aid
user with/ without DSP. Group (A, γ) Positive Negative Group
outcome outcome total
Where Group (A, β) could be used as control Group 57% 43% 14%
group, since it is formed by first time hearing aid (A, α)
users. Group 65% 35% 30%
(A, β)
Effect of relief DSP (±100 %) nDSP=±1
Group 54% 46% 8%
- Group (A, α), n1 = 0.14 [-0.43, 0.57] => n1=14% (A, γ)
Group 51% 49% 2%
- Group (A, β), n2 = 0.3 [-0.35, 0.65] => n2=30% (A, α)
- Group (A, γ), n3 = 0.08 [-0.46, 0.54] => n3=8% Group 59% 41% 18%
(A, β)
As a total of group, A: nA = (n1+n2+n3)/3 nA =
(14+30+8)/3=17.33%
The studies revealed only one consistent effect,
Another 2 different results were obtained with namely that listening effort was higher for
group B when taking outcomes after being fitted hearing impaired listeners compared with
first with analogic hearing aids between one and normal hearing listeners but the evidence across
three months even for those who are them failed to reveal consistent flagrant effects
on listening effort when using DSP until hearing
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
15SAERA - RESEARCH ARTICLE
aid industry specifies every case as unique and percentage (%) and varies between negative
gives it the necessary care with the and positive values.
collaboration and improvement of multiple
industries in the purpose of evolving subject In fact, 3 different results in 3 different studies
diagnoses, not to forget that DSP is surprisingly were obtained with group C when taking
evolving on a linear scale basis and still, a lot has outcomes after being fitted first with
to be waited to come. omnidirectional hearing aids between one and
three months even for those who are
Directionality experienced users then fitted similarly between
one and three months with directional hearing
Table2. Outcome of nDirect aids.
Positive Negative Group Effect of relief Direct (±100%) nDirect=±1
outcome outcome total
Group 49% 51% -2% Experienced bilateral fitted sensorineural
(C, α) hearing loss with/ without symmetrical
Group 59% 41% 18% directionality utilizing traditional directional
(C, β) systems Group (C, α).
Group 57% 43% 14% - Group (C, α), n1 = -0.02 [-0.51, 0.49] => n1= -
(C, γ) 2%
Group 55% 45% 10%
(D, α) Experienced bilateral fitted sensorineural
Group 52% 48% 4% hearing loss with/ without symmetrical
(D, β) directionality utilizing split band, hybrid and
adaptive directionality Group (C, β) and (CMS).
Proof relating to Q2 comparing hearing aid - Group (C, β), n2 = 0.18 [-0.41, 0.59] => n2= 18%
results with and without directionality systems, - Group (C, γ), n3 = 0.14 [-0.43, 0.57] => n3= 14%
given by 4 studies. They mainly provided speech
recognition outcomes when testing hearing aids Another 2 different results were obtained in the
on participants with moderate to profound same study with symmetrical and asymmetrical
hearing loss. Participants are mainly adults with directionality. Outcomes were extracted after
ranging age between 54 and 62 years old. The fitting participants first with omnidirectional
majority of participants were experienced hearing aids for 45 days then with directional
hearing aid users with sensorineural hearing ones for another 45 days.
loss; just one group of one study was divided
- Experienced bilateral fitted sensorineural
into symmetric and asymmetric users.
hearing loss with/ without symmetrical
Directional systems utilized dual microphones
directionality utilizing hybrid and split band
with split band, hybrid and adaptive
directional systems. Group (D, α)
directionality. Experiment included self and
relatives or friend’s outcomes. Speech - Group (D, α), n4 = 0.1 [-0.45, 0.55] => n4= 10%
recognition outcomes were reported for word
and sentence recognition. - Experienced bilateral fitted sensorineural
hearing loss with/ without asymmetrical
The dependant variable was named ‘The effect directionality utilizing hybrid and split band
of relief with Direct’ (nDirect). It is measured in directional systems. Group (D, β)
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
16SAERA - RESEARCH ARTICLE
- Group (D, β), n5 = 0.4 [-0.48, 0.52] => n5= 4% may vastly affect the awareness of sensing the
difference.
Combined result while comparing directional vs
non directional systems is: Knowing that all is not enough if the clinician
doesn’t understand the benefits and limitations
n6 = (n5+n4)/2 = (10+4)/2 = 7% of each feature available today to perform an
Final Effect relief of directionality: appropriate programming in the purpose of
achieving a proper fitting added to the fact that
nDirect= (n1+n2+n3+n6)/ 4= (-2+18+14+7)/ 4= a good counseling will offer the hearing aid user
9.25% => nDirect~ 0.093 the capability of taking a good advantage of the
Processing signal in a hearing aid may result in devices with the possibility to hear in noisy
more natural sound quality for the end user but situations.
preserves the directional benefit of traditional
directional settings. Asymmetric directional DISCUSSION
fitting, provides a directional pattern creating a
balance between environmental awareness and Nowadays, hearing aids have numerous
directional advantage. In summary it resulted programmed features: turning directionality
that those listeners indicated an overwhelming
and noise reduction and making adjustments to
preference for the sound quality of
the hearing aid settings. This computerization
omnidirectional processing over traditional
directional processing, and preferred will proceed to advance. Current adaptive
asymmetric directional fitting over traditional algorithms in hearing aids should not be
directionality more than twice as often while classified as they have the capacity to progress
keeping the bilateral new directional systems over time in reaction to sensor data. Methods
the gold standard for a slight improvement in such as neural systems and hereditary
the sake of end user advantage algorithms have been researched vastly in the
universities for utilization in systems and we
An additional advantage of processing sound
ought to expect their rise into the hearing aid
through binaural wireless communication is the
spectral preservation of timing, giving the industry. Surprisingly, little investigation in
advantage to the hearing aid bilateral user of these regions has contributed to hearing aid
natural timing differences that are important for design and fitting. The articulation list has been
sound localization. In fact, nearly eliminating utilized to optimize the perceptibility of speech,
time difference will maintain an important cue and loudness recruitment has driven to the
of binaural communication that preserves fitting of multiband compression added to other
localization of sound, the results indicated that hearing aid algorithms based on the
binaural communication could be mismatched psychoacoustics of hearing impairment have
up to 6dB by compression and affect localization not been very successful. The future will see the
performance as long as cues are interrupted or effective application of hearing science to DSP
not available. Rather, the user didn’t express a
innovation developments, but most of the
much great difference in result between
progress will require a coordinated
binaurally communicating hearing aids and non
communicating ones. Of course, he felt the improvement of modern diagnostics, signal
difference with the attenuation by compression processing, and validation measures. Hearing
but revealed nearly the same results. Noting aid industry will change as it changes how it
that, the variability of surrounding atmosphere looks to the pathologies and needs of every
Abdel Nour, J. R. (2022). Effect of Hearing Aid Evolution on Hearing Impaired perceptibility. SAERA. School of
Advanced Education, Research and Accreditation.
17You can also read
