Innovations in Hearing Aids: Bluetooth and Beyond
According to the National Institute on Deafness and Other Communication Disorders (NIDCD), approximately 15% of American adults report some trouble with their hearing. For many of these people, a hearing aid can help not only by optimizing the quality of their hearing but also acting to enhance their general wellbeing.
As an assistant professor in the Doctor of Audiology degree program at Texas Tech University Health Sciences Center School of Health Professions (TTUHSC SHP), Dr. Renee Zimmerman, AuD, CCC-A teaches students how audiologists treat hearing loss with hearing aids and cochlear implants.
Zimmerman explains that there are many different levels of hearing loss.
“People often think of hearing loss as a yes or no question — I can hear or I cannot hear — and that's very much not true,” says Zimmerman. “There is a whole range of hearing loss from mild to moderate, moderately severe, severe, and profound.”
Regardless of the level of hearing loss experienced, Zimmerman recommends that it should never be ignored.
“A lot of times people think that if they just have a mild hearing loss — it's just mild and they don’t need to do anything about it,” says Zimmerman. “However, there's a lot of research that shows that children with mild hearing loss are at greater risk of academic difficulties and are at greater risk of repeating grades. For adults who have mild hearing loss, they may not notice any difficulty in quiet environments — but put them in an environment with a lot of background noise, and all of a sudden that person starts to have more difficulty. The research also indicates that people who have hearing loss tend to withdraw from their life because it’s so difficult to communicate.”
Zimmerman demonstrates the impact of hearing loss to her students by encouraging them to wear earplugs for a 24-hour period.
“Even after 24 hours, they talk about how embarrassed they get, having to ask people to repeat things and how self-conscious they feel about not being able to understand things, particularly when they go out to crowded or noisy social environments,” says Zimmerman. “For them, it’s just 24 hours and they know that tomorrow things will be better, but for somebody who’s experiencing hearing loss, they tend to decline social invitations and withdraw from the things they used to find enjoyable.”
What Causes Hearing Loss?
There are many reasons why someone might experience hearing loss.
“They could be born with it,” says Zimmerman. “There are illnesses that could cause hearing loss like measles or mumps and there are a lot of reasons why preventing those kinds of diseases is so important to prevent hearing loss. Of course, you've also got noise-induced hearing loss affecting people who work around loud noises, loud machinery, loud music or people who are recreationally around those kinds of things.”
Hearing loss is also common in older people.
“There's a significant population over the age of 70 who would be expected to experience hearing loss,” says Zimmerman.
Regardless of the cause of hearing loss, Zimmerman insists that the vast majority of people affected will benefit from a professionally fitted hearing aid.
How Do Hearing Aids Help?
Audiologists refer to hearing aids as amplification because, at their root, they make sounds louder. However, they are sophisticated devices; they don’t simply make everything louder like the volume control of your television set or radio.
“The difference between the volume control on your television and a hearing aid is that with a hearing aid, an audiologist will first test your hearing first and set what we call prescriptive targets,” says Zimmerman. “Most people don't have the same amount of hearing loss at all the different pitches. They typically have more hearing loss in the higher pitches — those treble tones, and they have less in the bass tones.”
Hearing aids also help balance the volume of soft and loud sounds.
“When somebody has hearing loss, they often become unable to hear soft sounds but loud sounds are still perfectly loud,” says Zimmerman. “Sometimes people who have hearing loss cannot tolerate loud sounds as well as normal hearing people can. So not only do hearing aids apply different amounts of amplification for all of the different pitches, but they also apply different amplification based on the volume of the incoming sound. So at its most basic level, a hearing aid is trying to make inaudible sounds audible, while still maintaining comfort for the listener.”
Once an audiologist has adjusted all the settings relating to a pitch and volume that’s right for the listener, they can then start thinking about things like background noise.
“Hearing aids have settings in them that identify what is background noise and what is speech,” says Zimmerman. “These settings try to reduce or eliminate the effect of that background noise and enhance the speech signal so that we can make the speech audible. Remember, that person with a mild hearing loss can hear just fine in a quiet environment. They really didn't need a lot of amplification because they were able to hear enough of the signal, their brain filled in the parts they didn't hear and they understood everything that was said. But then when I put them in background noise, they hear less of the signal and their brain doesn't have enough of the resources to put what they need back in.”
Due to the complex and highly individual nature of hearing loss, Zimmerman warns patients against opting for less sophisticated amplification devices.
“Sometimes you will see these amplifier products sold in drug stores or on the internet,” says Zimmerman. “They are not really hearing aids because they are not specifically set for the person's hearing loss and they have at best a very basic or rudimentary noise reduction system in them.”
Zimmerman also warns that by bypassing professional diagnosis, people with hearing loss might be ignoring a more serious medical complaint.
“For most people, the difficulty they are having is related to their hearing sense organ called their cochlea,” says Zimmerman. “However, there are some individuals for whom that is not actually their problem. They either have some kind of medical condition going on with their eardrum or their ear bones or maybe they have some neurologic problem. If you simply buy one of these devices at a drug store and put them on you are going to miss identifying that you might need medical treatment. As an audiologist, part of my job is to know when a patient has a simple hearing loss or when there is something more going on and they need to go and see a physician.”
For some patients, a hearing aid might not provide enough amplification to benefit their hearing. In such cases, a cochlear implant is recommended.
“Hearing aids are a non-invasive option,” says Zimmerman. “You program them on the computer and you put them on the person's ears. With a cochlear implant, there's a surgical procedure where they insert a thin electrode array into the cochlea. In our cochlea, we have these little hair cells that vibrate in response to sound, and as they vibrate they create electrical signals that connect to the nerve and send the signals on. In a cochlear implant, we are essentially skipping those hair cells because they don't work anymore.”
Zimmerman explains how the cochlear implant differs from a traditional hearing aid.
“Just like the hearing aid, there's a microphone on it to pick up the sound and a processor that processes that sound,” says Zimmerman. “The difference is that instead of having a speaker that creates sound that then goes to the ear, it actually goes through an antenna to an internal device that then processes that signal again and sends it electrically into that electrode array.”
According to Zimmerman, for those that cannot benefit from traditional hearing aids, there are very few people that an implant won't help. But results can differ from person to person. “Some people might have some sort of neurologic issue — so their nerve isn't functioning," says Zimmerman. "Some other things that might affect outcomes related to spoken language production are age when hearing was lost and the length of time between hearing loss and the use of amplification. In general, for children, the best results for producing spoken language occur when getting a hearing aid or cochlear implant at a young age. The best outcomes for adults are generally associated with receiving amplification quickly once a hearing loss occurs. Adults with little or no experience with listening to sound tend to benefit less from amplification. So, if I have a teenager or an adult who has never used their hearing for listening to language, they could get an implant, but they might not get a language or communication benefit.”
Bluetooth Hearing Aids and Other Innovations
According to Zimmerman, hearing loss assistive technology is an ever-changing environment with manufacturers launching new hearing aids every 12 to 18 months.
“We're actually developing a little bit less in the areas of speech understanding because I think we've kind of plateaued in that arena,” says Zimmerman. “One of the more recent developments is that hearing aids communicate with each other wirelessly.”
By communicating with each other, hearing aids are better able to analyze and process the sound landscape around the listener.
“If you have two hearing aids, you've got two microphones on one device and two microphones on the other,” says Zimmerman. “These four microphones talk to each other and analyze the environment in 360 degrees. We used to say that the microphones that pick-up speech should face forward and microphones that pick-up noise face backward. Now we can identify in 360 degrees where that speech signal is coming from and provide the clearest signal to both hearing aids based on the input of all four microphones.”
Connectivity is another area where Zimmerman sees growth.
“As a world, we are becoming more connected," says Zimmerman. "Our everyday technology devices are becoming more connected and so the hearing aid manufacturers are really moving in the direction of making sure that your hearing aid integrates seamlessly into that connected environment. So hearing aids are increasingly connecting to your phone, to your television, to any other Bluetooth devices that you may have in your environment — and doing so wirelessly.”
The opportunity to connect hearing aids with other devices is particularly exciting to younger people who may have previously been reluctant to wear a hearing aid.
“Let's think about the teenager who has hearing loss,” says Zimmerman. “Their smartphone and their tablet are just as important to them as it is to the kid who doesn't have hearing loss. They want to be able to stream music, videos, and podcasts just like their friends who wear headphones. We don't want them to take the hearing aids out and put a set of headphones in. We want the hearing aids to function as the headphones because they've been programmed for their hearing. It's very much a question of getting your hearing aids to integrate with your lifestyle.”
Health tracking is another area that some hearing aid manufacturers are looking to
“Hearing aids are starting to use Artificial Intelligence (AI) to monitor activity in a person’s day,” says Zimmerman. “They are looking at the types of environments people are in, and what kind of stimulus they are receiving. Some manufacturers are experimenting with things like monitoring a person’s pulse and temperature out of the ear. The idea is that hearing is part of overall wellness and that somebody who is not hearing well might miss out on part of the wellness picture.”
Where do Audiologists Work?
According to Zimmerman, audiologists can be found working across a range of professional environments.
“The majority of audiologists are going to work in either a private clinic where they test hearing and fit devices, in hospital clinics, or you might see them paired-up with ear, nose, and throat (ENT) physicians,” says Zimmerman. “ENTs use hearing tests as part of their diagnostic procedure, so most ENTs will have an audiologist on staff with them.
Audiologists also work in school systems, across industries where employees may be exposed to noise, and with organizations like the US Department for Veteran’s Affairs (VA).
According to the Bureau of Labor Statistics (BLS), the median annual wage for an audiologist is $75,920. Prospects for graduates in the field are also good with the job outlook projected to grow by 16% by 2028 — much faster than average.
To learn more about launching your career as an audiologist or to talk with our staff about your interest in the Doctor of Audiology program at TTUHSC SHP, please visit the program page on our website.
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