Unlocking the Potential for Hair Cell Regeneration

By Laura Friedman

On November 5, 2015, Hearing Health Foundation hosted its second live-video research briefing as part of our effort to provide regular updates on our research programs and progress. Through these briefings, our goal is for our attendees to obtain new information and understanding about hearing loss, prevention and research toward a cure.


Dr. Andy Groves, Hearing Restoration Project consortium member, presented recent research advances and new discoveries, the use of new technology, and our future plans to prevent and cure hearing loss and tinnitus. The HRP was founded in 2011 and is the first and only international research consortium focused on investigating hair cell regeneration as a cure for hearing loss and tinnitus. The overarching principle of the consortium is collaboration: open sharing of data and ideas. The HRP consortium consists of 13 of the top investigators in the audiological space, as well as a scientific director, Dr. Barr-Gillespie.

We wanted to share with you highlights from the presentation, which is available to watch with live captioning or to read with notes summarizing each slide.

Your Support Is Needed!

Hair cell regeneration is a plausible goal for eventual treatment of hearing and balance disorders. 

The question is not if we will regenerate hair cells in humans, but when.  

However, we need your support to continue this vital research and find a cure! Please make your gift today. 

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#HearTheHope This Holiday Season

By Laura Friedman

#GivingTuesday 2015, an international day of giving that kicks off the holiday giving season, is just around the corner on December 1st.

Hearing Health Foundation (HHF) wants to thank you for your continued support of our mission and programs, such as the Hearing Restoration Project (HRP) and Emerging Research Grants (ERG). Your support matters and has, and will continue to, enhance the lives of millions of Americans. Here are some of our successes, dating back to our founding in 1958:

  • HHF is the largest private funder of hearing research in the U.S.

  • HHF funded research has led to:

    • The development of cochlear implants

    • Treatments for otosclerosis (abnormal bone growth in the ear) and ear infections.

  • In 1985, scientists funded through the ERG program discovered that chickens regenerate their inner ear hair cells after damage and mammals do not. This study led to the development of the HRP in 2011.

  • In the 1990s HHF advocated for Universal Newborn Hearing Screening legislation, to detect hearing loss at birth.

    • Today, 97% of newborns are tested (up from 4% in 1994).

The work doesn't stop there. Your support will continue to impact the course of hearing and balance science and help us find a cure for the 50 million Americans living with hearing loss and tinnitus. The question of finding a cure for hearing loss is not if, but when. Making a financial commitment to HHF is an investment in our future. But we need YOUR help. Here are some ways you can #HearTheHope this holiday season:

  • Make a donation to HHF in honor or in memory of someone close to you.

  • Post on social media, such as Facebook or Twitter, encouraging your friends to donate to HHF.

    • The average person has 300 friends on Facebook which means that if each of your friends donates just $1 on Giving Tuesday, you can raise $300 in one day—it’s that easy!

  • Contribute to an item on our Wish List and give our researchers the tools they need.

  • You can make gifts of appreciated stocks or a planned gift!

  • Let your talents and interests lead you to your own fundraiser for HHF through our website! No event is too large or small. Here are some ideas for inspiration:

    • Host a potluck and invite your guest to join you by bringing a dish and making a donation to HHF.

    • Hold a bake sale or golf outing and advertise that the proceeds will be donated to HHF.

    • Burn excess Thanksgiving calories and go for a run, swim (indoors of course!), or bike ride, fundraising for every mile accomplished.

Have other ideas or questions for us? E-mail us at Development@hhf.org.

Any donation you send before December 31st will be instantly doubled thanks to a generous matching gift from one of our supporters with hearing loss — and you will make twice the IMPACT!

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Selective Attention or Selective Hearing?

By Ross K Maddox, Huriye Atilgan, Jennifer K Bizley, Adrian KC Lee

In the noisy din of a cocktail party, there are many sources of sound that compete for our attention. Even so, we can easily block out the noise and focus on a conversation, especially when we are talking to someone in front of us.

 

This is possible in part because our sensory system combines inputs from our senses. Scientists have proposed that our perception is stronger when we can hear and see something at the same time, as opposed to just being able to hear it. For example, if we tried to talk to someone on a phone during a cocktail party, the background noise would probably drown out the conversation. However, when we can see the person we are talking to, it is easier to hold a conversation.

Maddox et al. have now explored this phenomenon in experiments that involved human subjects listening to an audio stream that was masked by background sound. While listening, the subjects also watched completely irrelevant videos that moved in sync with either the audio stream or with the background sound. The subjects then had to perform a task that involved pushing a button when they heard random changes (such as subtle changes in tone or pitch) in the audio stream.

The experiment showed that the subjects performed well when they saw a video that was in sync with the audio stream. However, their performance dropped when the video was in sync with the background sound. This suggests that when we hold a conversation during a noisy cocktail party, seeing the other person's face move as they talk creates a combined audio–visual impression of that person, helping us separate what they are saying from all the noise in the background. However, if we turn to look at other guests, we become distracted and the conversation may become lost.

This post originally appeared on eLife Science on Feb 5, 2015 in reference to the scienctific publication, "Auditory selective attention is enhanced by a task-irrelevant temporally coherent visual stimulus in human listeners." HHF amended the title from the original publication, permitted through Creative Commons

We need your help in funding the exciting work of hearing and balance scientists. 

To donate today to Hearing Health Foundation and support groundbreaking research, visit hhf.org/name-a-grant.

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How Noise Affects the Palate

By Melissa Osgood, Cornell University

If you're planning to fly over the holiday, plan to drink some tomato juice. While examining how airplane noise affects the palate, Cornell University food scientists found sweetness suppressed and a tasty, tender tomato surprise: umami.

A Japanese scientific term, umami describes the sweet, savory taste of amino acids such as glutamate in foods like tomato juice, and according to the new study, in noisy situations -- like the 85 decibels aboard a jetliner -- umami-rich foods become your taste bud's best buds.

"Our study confirmed that in an environment of loud noise, our sense of taste is compromised. Interestingly, this was specific to sweet and umami tastes, with sweet taste inhibited and umami taste significantly enhanced," said Robin Dando, assistant professor of food science. "The multisensory properties of the environment where we consume our food can alter our perception of the foods we eat."

With Dando, Kimberly Yan, co-authored the study, "A Crossmodal Role for Audition in Taste Perception," published online in March in the Journal of Experimental Psychology: Human Perception and Performance. The research will appear in a forthcoming print edition of the journal.

The study may guide reconfiguration of airline food menus to make airline food taste better. Auditory conditions in air travel actually may enhance umami, the researchers found. In contrast, exposure to the loud noise condition dulled sweet taste ratings.

Airlines acknowledge the phenomenon. German airline Lufthansa had noticed that passengers were consuming as much tomato juice as beer. The airline commissioned a private study released last fall that showed cabin pressure enhanced tomato juice taste.

Taste perception depends not only on the integration of several sensory inputs associated with the food or drink itself, but also on the sensory attributes of the environment in which the food is consumed, the scientists say.

"The multisensory nature of what we consider 'flavor' is undoubtedly underpinned by complex central and peripheral interactions," said Dando. "Our results characterize a novel sensory interaction, with intriguing implications for the effect of the environment in which we consume food."

The above post is reprinted from materials provided by Cornell University.

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How Hearing Loss and Tinnitus Affect Our Veterans

By Emily Shepard

Today is Veterans Day. The holiday is important not only because it honors our soldiers, but also because it is a time to raise awareness about their experiences on and off the battlefield. Hearing loss is a major health issue for soldiers, both active duty personnel and veterans. Any form of hearing loss can be detrimental to soldiers on duty, as the ability to hear signs of danger and to communicate with fellow soldiers is crucial for mission success and, more importantly, survival. According to the U.S. Department of Defense’s Hearing Center of Excellence (HCE), a whopping 60% of veterans have returned home with hearing loss or tinnitus over the last decade.

The Fall 2015 issue of Hearing Health magazine focused on hearing loss and tinnitus among U.S. military service members and veterans. In “Tuning Out the Noise,” Ashleigh Byrnes explains that tinnitus is one of the most prevalent injuries among veterans.  The number of veterans diagnosed with service-connected tinnitus is estimated at 1.5 million. According to Byrnes, persistent tinnitus can be “described as noise that prevents sleep or the ability to concentrate” and may “leave patients more vulnerable to other mental health problems, such as depression and anxiety.” Luckily, there are treatment methods, new and old, that can ease the symptoms of tinnitus. 

Sound therapy, long regarded as one of the most successful ways to treat tinnitus, has been practiced for more than 30 years. Between 60-90% of patients report relief from their symptoms using this method. Another option is cognitive behavioral therapy (CBT), which may include the use of relaxation or distraction techniques, or altering the way patients think about their symptoms. Those who try sound therapy or CBT may be able to cope with tinnitus with more positive outcomes.

When it comes to hearing loss, soldiers are at an increased risk. They are susceptible to noise-induced hearing loss (NIHL) due to exposure to loud machinery and explosions on a constant basis. In combat, soldiers are often exposed to sudden noises, such as from an improvised explosive device (IED) or other similar weapons, which are difficult to predict and prevent against.  These sudden noises can result in temporary hearing loss and put military personnel at risk. However, the word “temporary” should be approached with caution. Repeated short-term hearing loss can damage the sensitive hair cells in the inner ear, causing hearing loss that becomes permanent.

With an inability to grow back, inner ear hair cells, when they are damaged or die, can lead to permanent hearing loss. HHF is actively working to reverse this trend. Researchers funded by HHF’s Emerging Research Grants program (ERG) discovered that birds have the ability to spontaneously re-grow inner ear hair cells after they are damaged and restore their hearing—unlike mammals. Through HHF’s Hearing Restoration Project (HRP), a consortium of top hearing scientists is working to translate this finding to the human ear. The HRP’s goal is to regenerate inner ear hair cells in humans and permanently restore hearing to those affected by hearing loss, such as soldiers and veterans. The HRP researchers have made significant strides in this research and have been working hard to find meaningful answers, which you can read about here.

To learn more about hearing loss and tinnitus, please visit our Veterans’ Resource Page.

Your support helps us continue this extraordinary research.

Celebrate Veterans Day and honor our troops by donating today.

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Handicapable

By Kate Yandell

Dominic Pisano hadn’t even arrived on campus to start his freshman year at Johns Hopkins University when he got his first email from biomedical engineer Tilak Ratnanather. He had heard Pisano was deaf and wanted to meet with him. Ratnanather, who has been deaf since birth, showed up for the meeting accompanied by a second deaf student who would later become a doctor. “He was, like: ‘Here’s my deaf army,’” Pisano recalls.

Soon, Pisano, a soccer enthusiast from Ohio, was interpreting magnetic resonance imaging (MRI) in Ratnanather’s department. When Pisano decided he wanted to go to medical school, Ratnanather was ready to introduce him to his wide network of friends in the otolaryngology department at Hopkins. Pisano assisted in MRI research at Hopkins for a year before attending Tufts University School of Medicine in Boston.

“I’ll be honest with you, if it weren’t for Tilak I probably wouldn’t have gone to medical school,” says Pisano, now a resident in anesthesiology at Tufts Medical Center. “I probably wouldn’t have done biomedical engineering research. Most importantly, I probably wouldn’t have the kind of network I have.”

Photo: Tilak RatnanatherCourtesy Johns Hopkins School of Medicine

Photo: Tilak Ratnanather

Courtesy Johns Hopkins School of Medicine

It was this kind of service that won Ratnanather the Presidential Award for Excellence in Science, Mathematics, and Engineering Mentoring this past March. Over the years, Ratnanather has lobbied for better resources for deaf attendees at conferences, organized annual dinners for deaf researchers, helped award scholarships to hearing-impaired students through the Alexander Graham Bell Association for the Deaf and Hard of Hearing (AG Bell), and mentored more than a dozen hearing-impaired students.

“He’s by nature the most gregarious and extroverted individual,” says Howard Francis, a professor of otolaryngology at Hopkins who has known Ratnanather for 23 years. “He has a sense of mission and is committed to making it possible for others to achieve what he has achieved.”

“A lot of people have a hard time understanding him [due to his deafness-related difficulties with speech],” says Pisano, “but despite that, they still enjoy his company, and they want to be connected with him.”

Ratnanather was born in 1963 in Sri Lanka with profound hearing loss of unknown origin. His family moved to London when he was 18 months old, and he grew up wearing hearing aids and attending the Mary Hare School for Deaf Children.

Ratnanather’s parents, a pediatrician and a computer systems programmer, had high hopes for their son. “My father and I would talk about mathematics and would go through some problems at home,” he says. “I had an aptitude, and then, of course, I would go to the science museum and learn about famous mathematicians.” Ratnanather enrolled at University College London, where he met mathematician Keith Stewartson, who immediately made the young undergrad comfortable about his hearing loss and the assistive technologies he needed to use in the classroom. “I knew he would make my life easy,” says Ratnanather. “I didn’t have to worry about my deafness.”

Tragically, Stewartson died suddenly at the end of Ratnanather’s first year at university. But the young student forged ahead, and after doing some reading about Stewartson’s research on fluid dynamics, Ratnanather went on to study the subject in graduate school at the University of Oxford, receiving his D.Phil. in mathematics in 1989.

Up until that point, Ratnanather had only had occasional opportunities to learn about an area near to his heart: hearing research. This changed after he attended a research symposium at the 1990 AG Bell Convention in Washington, D.C. Fascinated by the work of William Brownell, Ratnanather approached the Johns Hopkins researcher after Brownell had given a talk about outer hair cell electromotility—the process by which these sensory cells shorten or lengthen in response to electrical impulses.

When outer hair cells change shape, they transmit mechanical force to the cochlea, amplifying the ear’s sensitivity to soft sounds at specific frequencies. Forces transmitted through pressurized fluids in outer hair cells make electromotility possible, explains Brownell, who is now at Baylor College of Medicine in Houston. He needed someone who could model the dynamics of fluid within these tiny spaces. “Tilak had the computational tools to begin to study this,” Brownell says.

Ratnanather began a postdoc in Brownell’s lab in 1991. During his postdoc, he realized he could bestow upon students the confidence his mentors fostered in him. The Internet helped him reach out to other deaf people through newsgroups. Lina Reiss, who had severe hearing loss by age 2, first met Ratnanather when she was an undergraduate at Princeton University and he replied to an online post in which she introduced herself to one of these newsgroups.

The daughter of two Ph.D.s, Reiss had always known that she wanted to go into the sciences. But she was not sure what career would be possible with her hearing loss. “I didn’t have any role models of what it was like to be a deaf faculty member,” she recalls. “Until I met [Tilak and some of his deaf friends], I couldn’t imagine becoming a professor.”

Ratnanather helped get Reiss a summer internship in the hearing-research lab of a colleague at Johns Hopkins, where she studied how neurons in the brain stem encode and process sound. Enthralled with the research, she went on to do her Ph.D. in biomedical engineering in the same lab. She is now an assistant professor at Oregon Health & Science University in Portland researching how hearing loss, hearing aids, and cochlear implants influence the way people perceive sound.

Ratnanather now primarily does brain-mapping research focused on understanding how brain structures are altered in people with diseases such as schizophrenia, Alzheimer’s, and bipolar disorder. But hearing science continues to influence his work. He has published several recent studies on fluid dynamics and hair cell function and has upcoming papers on imaging the auditory regions of the brain in deaf adults and babies.

And, spurred partly by his own cochlear implant surgery in 2012, Ratnanather has created an app for adults learning how to hear following the surgery. Called Speech Banana, the app is named after the banana-shaped region in an audiogram that contains human speech.

More than just providing professional connections, Ratnanather has influenced how his former students navigate the world. Being deaf can make it scary to think outside the box or challenge opinions, Pisano says.  Ratnanather encourages his mentees to keep an open mind and engage with others—hearing and nonhearing alike. “That helped shape my mentality about life in general today,” Pisano says.

Reprinted with permission. "Handicapable" originally appeared in the October 2015 issue of The Scientist, a special issue devoted to hearing research. The article can be accessed online here. See also The Scientist’s Facebook page, where this article generated many comments.

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Hearing Health Foundation is thrilled that Tilak Ratnanather, D.Phil., received this outstanding honor and recognition from the White House for his mentoring efforts. Ratnanather was a recipient of an Emerging Research Grant (ERG) in 1993, and has continued to champion HHF and its mission to prevent and cure hearing loss and tinnitus.

Dominic Pisano, M.D., who is quoted in this article, served on HHF’s inaugural National Junior Board (now known as HHF’s New York Council) in 2012. He has written about his decision to get a cochlear implant (CI) on our website and the tips and tricks he used to succeed in medical school in our magazine, and he appeared in an HHF public service announcement.

Also quoted in the article, Lina Reiss, Ph.D., was an ERG recipient in 2012 and 2013, and went on to win funding from the National Institute on Deafness and Other Communication and Disorders. She cowrote a piece about hybrid CIs and the way they make use of residual hearing ability. HHF congratulates all for their achievements!

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Hearing Loss Stigma?

By Terry Golson

Forty years ago I was a teenager with a mild hearing loss. An audiologist offered to fit me with bulky, ugly hearing aids. I said No thanks. But my loss was progressive and in my mid-twenties I finally got a hearing aid. It was a large plastic shell that filled the ear. It was uncomfortable and whistled from feedback, but it enabled me to hear. I wore it.

 

I wore my hair long and covered the aids. They were ugly and I didn’t want to have to talk about my disability unless I brought it up first.

My hearing worsened so that even with aids I struggled. I was constantly challenged in how to function with it. I wasn’t embarrassed by my loss, and I didn’t believe that people would think less of me because of it, but that didn’t lessen how difficult it was to live with a hearing loss. I’d tell people that I had trouble hearing, but it’s actually quite difficult for people to change how they speak. Some would project better for a word or two, but then resort back to their quiet voices. Early on in my loss I heard well enough to fill in the blanks. But, as my hearing declined, I couldn’t catch up. I’d miss half a sentence and nod in agreement, or I’d think that I understood something, but later would find out that I’d misheard. Also, like many people with hearing loss, it was easier to talk rather than to listen and so I would dominate a conversation, or would come across as rude because I missed the verbal clues as to when to enter and to end an interaction.

I was self-aware enough to recognize that this was happening. Eventually, I no longer cared if people saw my aids, in fact, I hoped that if they did they would speak more clearly. I wore my hair short, but no one noticed the aids. My hearing loss continued to worsen. I switched to behind-the-ear devices.  My ability to engage in conversation declined. Work options shrunk. I felt socially inept, visibly I came across as incompetent because of missed communication. Whatever judgements people were making about me, it was because of the behavior that the hearing loss caused, not what they saw in my ears.  I became even more open about my hearing loss. I discovered that once others understood what I was coping with, that they were generous and helpful. It wasn’t what was in my ears that caused any stigma – it was when people didn’t know that the aids were there!

No one thought less of me because of the devices I wore. This is truer now than ever before. Look around – most people have some sort of electronics attached to their heads. I now have cochlear implants. I still have short hair. People rarely notice them, but if they do, they don’t know what they are. Once, a stranger asked me about my “telephone.” I’ve had teenagers tell me that my CIs are really cool. The only people I’ve met who believe that there is a stigma to using hearing aids are the ones who wear them. A friend of mine has always hidden her disability because she worried that being open about it would impact on how people perceive her at her job. She’s a high-level manager at a world-renowned research lab. Recently a woman joined her team. At the first meeting this new hire announced that she wore hearing aids and there were times during communication that she would need help. No one blinked. These are people used to working with technology. They were interested and helpful. It took my friend aback. All of those years of struggling with her loss alone had been unnecessarily difficult.

I understand not wanting to show off one’s aids. I don’t want my hearing loss to be the first thing that one notices about me. Also, I’m vain enough to care that my CI’s are not beautiful. They’re the color of office furniture. But, there is hope. Another friend, Karen, recently upgraded her hearing aids to devices that are sleek and stylish. They are a vibrant blue to match her eyes. She says that her new aids are beautiful, and she’s right. Karen is 83 years old. Her hearing loss and her hearing aids have no stigma - not in her mind, and not to anyone around her. She’s a noted scientist and, because her devices enable her to stay in the hearing world, she continues to speak at conferences and is a mentor to many.

So let’s lay the idea of the stigma of wearing hearing aids to rest once and for all. It’s life without the aids that brings limitations. Now, if only my CIs were as pretty as Karen’s.

Terry Golson lives in a small town outside of Boston, Massachusetts. You can read about her work and her life at her website, HenCam.com

 

Receive updates on life-changing hearing research and resources by subscribing to HHF's free quarterly magazine and e-newsletter.

 
 
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Best Supporting Actors - In Your Ears?

By the University of Michigan Health System

This microscopic view of cells deep within the ear of a newborn mouse show in red and blue the supporting cells that surround the hair cells (green) that send sound signals to the brain. New research shows that the supporting cells can regenerate if…

This microscopic view of cells deep within the ear of a newborn mouse show in red and blue the supporting cells that surround the hair cells (green) that send sound signals to the brain. New research shows that the supporting cells can regenerate if damaged in the first days of life, allowing hearing to develop normally. This gives new clues for potential ways to restore hearing.


Credit: Guoqiang Wan, Univ. of Michigan

There’s a cast of characters deep inside your ears -- many kinds of tiny cells working together to allow you to hear. The lead actors, called hair cells, play the crucial role in carrying sound signals to the brain.

But new research shows that when it comes to restoring lost hearing ability, the spotlight may fall on some of the ear’s supporting actors – and their understudies.

In a new paper published online first by the Proceedings of the National Academy of Sciences, researchers from the University of Michigan Medical SchoolSt. Jude Children’s Research Hospital and colleagues report the results of in-depth studies of these cells, fittingly called supporting cells.  

The research shows that damage to the supporting cells in the mature mouse results in the loss of hair cells and profound deafness. But the big surprise of this study was that if supporting cells are lost in the newborn mouse, the ear rapidly regenerates new supporting cells – resulting in complete preservation of hearing. This remarkable regeneration resulted from cells from an adjacent structure moving in and transforming into full-fledged supporting cells. 

It was as if a supporting actor couldn’t perform, and his young understudy stepped in suddenly to carry on the performance and support the lead actor -- with award-winning results.

The finding not only shows that deafness can result from loss of supporting cells -- it reveals a previously unknown ability to regenerate supporting cells that’s present only for a few days after birth in the mice.

If scientists can determine what’s going on inside these cells, they might be able to harness it to find new approaches to regenerating auditory cells and restoring hearing in humans of all ages.

Senior author and U-M Kresge Hearing Research Institute director Gabriel Corfas, Ph.D., says the research shows that supporting cells play a more critical role in hearing than they get credit for.

In fact, he says, efforts to restore hearing by making new hair cells out of supporting cells may fail, unless researchers also work to replace the supporting cells. “We had known that losing hair cells results in deafness, and there has been an effort to find a way to regenerated these specialized cells. One idea has been to induce supporting cells to become hair cells. Now we discover that losing supporting cells kills hair cells as well,” he explains.

“And now, we’ve found that there’s an intrinsic regenerative potential in the very early days of life that we could harness as we work to cure deafness,” continues Corfas, who is a professor in the U-M Department of Otolaryngology. “This is relevant to many forms of inherited and congenital deafness, and hearing loss due to age and noise exposure. If we can identify the molecules that are responsible for this regeneration, we may be able to turn back the clock inside these ears and regenerate lost cells.”

In the study, the “understudy” supporting cells found in a structure called the greater epithelial ridge transformed into full-fledged supporting cells after the researchers destroyed the mice’s own supporting cells with a precisely targeted toxin that didn’t affect hair cells. The new cells differentiated into the kinds that had been lost, called inner border cells and inner phalangeal cells.

“Hair cell loss can be a consequence of supporting cell dysfunctional or loss, suggesting that in many cases deafness could be primarily a supporting cell disease,” says Corfas. “Understanding the mechanisms that underlie these processes should help in the development of regenerative medicine strategies to treat deafness and vestibular disorders.”

Making sure that the inner ear has enough supporting cells, which themselves can transform into hair cells, will be a critical upstream step of any regenerative medicine approaches, he says.

Corfas and his colleagues continue to study the phenomenon, and hope to find drugs that can trigger the same regenerative powers that they saw in the newborn mice.

The research was a partnership between Corfas’ team at U-M and that of Jian Zuo, Ph.D., of St. Jude, and the two share senior authorship. Marcia M. Mellado Lagarde, Ph.D. of St. Jude and Guoqiang Wan, Ph.D., of U-M are co-first authors. Additional authors are LingLi Zhang of St. Jude, Corfas’ former colleagues at Harvard University Angelica R. Gigliello and John J. McInnis; and Yingxin Zhang and Dwight Bergles, both of Johns Hopkins University.

The research was funded by a Sir Henry Wellcome Fellowship, a Hearing Health Foundation Emerging Research Grant, the Boston Children’s Hospital Otolaryngology Foundation, National Institutes of Health grants DC004820, HD18655, DC006471, and CA21765; Office of Naval Research Grants N000140911014, N000141210191, and N000141210775, and by the American Lebanese Syrian Associated Charities of St. Jude Children’s Research Hospital.

The above post is reprinted from materials provided by University of Michigan Health System

  We need your help in funding the exciting work of hearing and balance scientists. 

To donate today to Hearing Health Foundation and support groundbreaking research, visit hhf.org/name-a-grant.

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How Hearing Loss Affects Other Aspects of Your Health

By Patricia Sarmiento

A few years ago, my dad began experiencing hearing loss. He worked in loud factories all his life. And while in recent years he began wearing ear protection, I think there were many days on the job where he didn’t use any. As he grew older, all that time without ear protection took its toll.

Prior to his experiences with hearing loss, I must admit that I didn’t know much about it. As he began going through the necessary steps, like getting fitted for hearing aids, I began to look into how hearing loss can affect our overall health. Here’s what I found:

Falls: This was my first area of concern when my dad’s hearing loss was diagnosed. I knew that our ears play an important role in our balance. However, I was surprised to see how significantly one’s chances of falling increased with their hearing loss. WhittierHearing.com cites a study that found that even just mild hearing loss meant you were “three times more likely to have a history of falling.” Of course, the older someone is the more dangerous these falls can be. My dad was lucky in that his hearing loss didn’t ever seem to affect him in this way. But if you have a loved one who has fallen or is experiencing balance issues, get their hearing checked!

Depression. We actually began suspecting that my dad was experiencing hearing loss long before he began seeking treatment for it. I think he was simply too proud to admit that he was having problems. We had to repeat ourselves to him and sometimes at family gatherings he would withdraw altogether. It was when he stopped going to his weekly Men’s Breakfast at our church that we knew something was going on.

While my dad received treatment before his hearing loss really began to take a toll on his mental health, I can definitely see how it could lead to depression. People experiencing hearing loss may experience poorer quality of life, isolation and reduced social activity.

Dementia. Through my research, I found out that in older adults there is a connection between hearing loss and dementia and Alzheimer’s. Those with mild hearing impairment are nearly twice as likely to develop dementia compared to those with normal hearing. The risk increases three-fold for those with moderate hearing loss, and five-fold for those with severe impairment. It isn’t yet clear what causes the connection, but the article says some researchers believe it may result from those with hearing loss straining “to decode sounds,” which may take its toll on the brain.

So, what can you do to protect your hearing? I’d like to suggest going for a swim. Here’s why: This guide on swimming and heart health notes what an excellent cardiovascular and full body workout swimming can be. That’s important because there have been many studies showing a connection between heart health and hearing. Yet another reason to be sure you’re getting plenty of exercise!

Patricia Sarmiento loves swimming and running. She channels her love of fitness and wellness into blogging about health and health-related topics. She played sports in high school and college and continues to make living an active lifestyle a goal for her and her family. She lives with her husband, two children, and their Shih Tzu in Maryland.

See our Hearing Health story, “Have a Hearing Loss, Have Another Health Issue?” for more information about health conditions associated with hearing loss.

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Does noise stress you out?

By Kathi Mestayer

Yes, it does.  In fact, noise stresses most people (and even many animals). 

But what is noise? My favorite definition is in the glossary of “Sound Matters,” a 2012 publication of the General Services Administration’s (GSA) Public Buildings Service:

 

Noise: Any undesired sound.”

 

So, if noise is undesired, it’s not that surprising that it’s stressful, right? In an article in Noise and Health, “Is There Evidence That Environmental Noise Is Immunotoxic?,” the author, Deepak Prasher, doesn’t mince words: “It is clear that noise is a stressor. The physiological response to noise as a stressor is no different from any other nonspecific physical stressor.” So, how does noise stress us out?

Danger! Danger! Warning! Warning!

Noise triggers a stress response in the amygdala, a region of the brainstem. Our amygdala learns, over time, what sounds might signal impending danger. When one is detected, the amygdala triggers a release of cortisol (a stress hormone) and an involuntary startle reaction. In his book, The Universal Sense: How Hearing Shapes the Mind, neuroscientist Seth Horowitz explains, “The auditory startle circuit is a very successful evolutionary adaptation to an unseen event. It lets us get our bearings and get the hell out of there, or at least widen our attention to figure out what the noise was.”

Cortisol affects us in many ways. According to Prasher, “In the acute stress reaction to an immediate threat, the secretion of stress hormones results in increased heart rate and blood pressure, a rapid release of energy in the bloodstream, reduced metabolism with a decrease in salivary and gastrointestinal activity, reduction in sex hormones, and activation of some immune functions.”

Over time, stress (often from transportation and industrial noise) can be particularly toxic. “This model of reactivity in terms of noise-induced stress has been implicated in the development of disorders of the cardiovascular system, sleep, learning, memory, motivation, problem-solving, aggression, and annoyance,” Prasher writes. If you think you’re getting used to that highway noise, think again.

Hearing loss and noise

So, people with hearing loss must be less sensitive to noise, right? Unfortunately, no—less hearing doesn’t mean higher noise tolerance. Research has been done on noise sensitivity and whether it correlates with a person’s audiogram. Here’s a summary of findings from the 2012 issue of Noise & Health:

“In the study of Stansfeld (1992), no significant differences were found in noise sensitivity between those with normal threshold of hearing and those with threshold impairment according to pure tone threshold audiometry. Likewise, Ellermeier et al. (2001) found no significant differences between two groups of low and high noise sensitivity in threshold levels, intensity discrimination, auditory reaction time or exponents for loudness functions. Our finding that the average hearing thresholds did not differ in noise sensitive and non-noise sensitive subjects is in concordance with previous studies.”

Anecdotally, this matches my audiologist’s observation that noise sensitivity is not correlated with our degree of hearing loss. “I always have to do a ‘sudden noise’ test with every person whose hearing aids I program before they leave my office. I can never predict who’s going to jump out of their skin and who’s not,” she says. 

In case you’re wondering, I jumped.

Staff writer Kathi Mestayer serves on advisory boards for the Virginia Department for the Deaf and Hard of Hearing and the Greater Richmond, Virginia, chapter of the Hearing Loss Association of America. This is adapted from her reader-sponsored work, “Be Hear Now."

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