Selecting the Right Earmuff

By Colin MacKenzie and Gary Klee

When combining hearing protection with safety glasses, face masks, etc., ensure performance is not adversely affected.

Wearing hearing protection can mean the difference between enjoying the sounds of everyday life and a lifetime of disability. Every day, we are exposed to potentially hazardous environmental noise. It is, therefore, critical that workers who must be present where the noise level is high and constant select either a muff or plug protector to reduce the noise level to an acceptable level. We will now discuss the factors you should consider when selecting the correct earmuff for the job.

Step 1: Determining Your Noise Level

Is the noise level and frequency content known (dB and Hz)?

If not, see the list of common noise sources on the next page. On some machines and power tools, you can find the dB level in the user manual or stated on a label on the machine.

If yes, follow this example: It is recommended that the calculated level under the earmuff should be under 85 dB (A). Therefore, subtract 85 dB from the noise level dB to find out the minimum protection level needed. The key is to provide enough attenuation but not enough to overprotect the wearer. Understand your whole-shift noise exposures and select the earmuff on the basis of that exposure, and do not use the highest measured noise level as your guide.

Example:

If you use a chainsaw, and the dB level is 110 dB (A). The recommended level under the ear cup should be below 85 dB (A). Therefore, you need an earmuff with an attenuation of at least 25 dB (110–85 =25).

When to consider selecting an earmuff with a lower protection level:

• Is the exposure time shorter than four hours? The earmuff protection level is based on noise exposure over an eight- hour working day. If the exposure is shorter, you should consider selecting a lower protection level.

• Do you need to hear important information from colleagues, warning signals etc.? Consider selecting a lower protection level or use an electronic level dependent earmuff.

• Are you suffering from hearing loss? If you have a hearing impairment, you may already have difficulty understanding speech in noisy environments. If you select the highest attenuation for hearing protectors, you may find it even more difficult to communicate or hear warning alarms.

• When to consider selecting an earmuff with a higher protection level:

• Does the noise consist mainly of low-frequency noise? If the noise is mainly low frequency, you should consider selecting a higher protection level because low-frequency noise is more difficult to block out.

• Do you need to wear safety glasses, face masks etc.? When combining hearing protection with safety glasses, face masks, etc., ensure performance is not adversely affected. If you are uncertain, seek additional advice and guidance or select an earmuff with a slightly higher protection level.

• Are there any other noise sources nearby? If there are other noise sources nearby, you should consider selecting a higher protection level.

Step 2: Choose the Correct Earmuff Style

• Are there any requirements to wear a hard hat at your workplace? If so, select a cap-mounted ear muff. Make sure that the hard hat you choose has universal slots that can be used in combination with the selected ear muff.

• Do you need to wear a bump cap or a hat for sun protection? Neckband ear muffs can be worn around the back of the neck, so users can wear them with bump caps, full-brim hard hats, or hats without attachment slots.

Step 3: Other Requirements

• Is the noise intermittent, or do you move in and out of noisy areas? Consider selecting an electronic level-dependent earmuff. The level-dependent earmuff protects against impulsive or intermittent hazardous noise while allowing situational awareness.

• Are you working with monotonous or stationary work tasks without the need to hear warning signals, etc.? Select an earmuff with a built-in AM/FM radio. Employees who wear radio earmuffs are more productive and motivated on the job.

• Are you working with monotonous work tasks and need to hear warning signals, etc.? Select an earmuff with both AM/FM radio and a level-dependent hearing function.

Common Noise Sources

Below are examples of different noise sources with their approximate sound pressure level in dB(A). These examples should only be used as guidance, as large variations may occur. The distance and surroundings also will affect the noise level.

Colin MacKenzie is President, Sales & Marketing at Hellberg Safety. Gary Klee is Product Manager, Above-the-Neck, at Protective Industrial Products Inc. (PIP), which is the exclusive supplier of Hellberg hearing protection in North America.

Photo Credit: Protective Industrial Products Inc.

12 Amazing Tips For Traveling With A Hearing Loss

By Janice Schacter Lintz

Having a hearing loss shouldn’t stop you from traveling. The following tips will ensure a smoother trip:

1. Sign up for travel alerts via email or text to avoid missing a flight. Gate/Flight Attendants, right or wrong, tend to forget to notify people of changes.
   

2. Have your hearing loss and any accommodation you need noted in your passenger/hotel profile in case of an emergency.
   

3. Specify in writing the specific HEARING access you need when booking a room. Otherwise, you are likely to receive a wheelchair accessible room. Hotels should offer a simple remote to activate the television’s closed captions, wake/shake/visual alerts and a hearing aid compatible telephone or TTY depending on your needs.
   

4. Research the places you plan to visit to determine the access available. Advise them ahead of time in writing, the accommodation you need. Send a letter if you do not receive the requested access. Access will only change when people complain.
   

5. Take extra batteries and back-ups of your hearing aids/processors. Running out of batteries can ruin a trip. The same is true if your hearing aid/processor breaks.
   

6. Bring a paper and pen to communicate in a noisy setting.
   

7. Pack a portable dehumidifier to dry out hearing aids/processors if traveling to a humid location. Sweat and humidity may affect their performance.
   

8. Transport all your supplies in a case in your carry-on bag to ensure everything remains intact. Store the bag in your in-room safe to avoid potential theft or loss. Check your homeowner’s policy to confirm coverage when traveling domestically and internationally.
   

9. Mention your hearing loss in advance to the TSA or customs personnel to avoid misunderstanding. Removing hearing aids/cochlear implant processors during TSA screening is unnecessary. Have a copy of the rules with you to avoid issues.
   

10. Load an iPad with movies since very few airlines offer closed captioning for in-flight programing. The good news is airlines such as Virgin are beginning to offer closed captions on some flights.
    

11. Take the hotel’s business card and written directions to ensure you arrive at the proper destination.
    

12. Safeguard your hearing aids/processors while swimming with AquaVault’s portable safe. It solves the issue of where to store your hearing aids when you remove them to swim. The lightweight safe attaches to the back of your lounge chair and easily fits in your luggage. A thief would have to remove he entire lounge chair to steal the safe.

Most importantly, have fun!

This piece was originally featured on JohnnyJet.com, a travel blog and resource committed to easier, better and cheaper travel.

The author, Janice Schacter Lintz, is the CEO of Hearing Access & Innovations, which works to improve accessibility for people with hearing loss. 

Orchestrating Hair Cell Regeneration

By the Stowers Institute for Medical Research

The older we get, the less likely we are to hear well, as our inner ear sensory hair cells succumb to age or injury. Intriguingly, humans are one-upped by fish here. Similar hair cells in a fish sensory system that dots their bodies and forms the lateral line, by which they discern water movement, are readily regenerated if damage or death occurs.

A neuromast sensory structure (green) of the zebrafish lateral line, which helps the fish detect water movement, is shown among surrounding cells (cell nuclei in red).

Credit: Piotrowski Lab, Stowers Institute for Medical Research

A new study in the July 16 online and August 10 print issue of Developmental Cell, from Stowers Institute for Medical Research Associate Investigator Tatjana Piotrowski, Ph.D., zeros in on an important component of this secret weapon in fish: the support cells that surround centrally-located hair cells in each garlic-shaped sensory organ, or neuromast. “We’ve known for some time that fish hair cells regenerate from support cells,” Piotrowski explains, “but it hasn’t been clear if all support cells are capable of this feat, or if subpopulations exist, each with different fates.”

While mammals also have support cells, they unfortunately do not respond to hair cell death in the same way. So understanding how zebrafish support cells respond to hair cell loss may provide insight into how mammalian support cells might be coaxed into regenerating hair cells as well. Zebrafish are particularly amenable to studies of regeneration because transparent embryos and larvae render developmental processes visible and experimentally accessible.

Piotrowski and her team treated zebrafish larvae with the antibiotic neomycin, which kills hair cells, then monitored support cell proliferation in regenerating neuromasts for three days using time-lapse movies. “These single cell lineage analyses were tremendously time-consuming but very informative,” Piotrowski notes. The study’s lead author, Andrés Romero-Carvajal, Ph.D., previously a predoctoral researcher at the Stowers Institute, carefully kept track of every individual support cell’s location and behavior across different time-lapse frames.

The researchers determined that approximately half of the dividing support cells differentiated into hair cells, while the rest self-renewed. Self-renewal is an equally important fate, Piotrowski points out, because it ensures maintenance of a reserve force that, if necessary, can spring into regenerative action. The researchers also observed that lineage fate of support cells hinged on where they were located in the neuromast, as self-renewing cells were found clustered at opposite poles while differentiating cells were distributed in a random, circular pattern close to the center. 

Such distinct support cell locations were “strongly indicative of differences in gene expression”, Piotrowski says, so the team turned its attention to exploring some of the genes and signaling pathways involved. A study of gene expression patterns showed that members of the Notch and Wnt pathways were expressed in different parts of the neuromast, specifically the Notch members in the center and the Wnt members at the poles. To determine if and how these two pathways regulate each other, the researchers used an inhibitor to turn off Notch signaling in neuromasts. This halt in Notch activity mimics the halt known to occur immediately after neomycin-induced hair cell death. After inhibitor treatment, they saw transient upregulation of Wnt ligands in the neuromast center, along with support cell proliferation. The majority of the proliferating cells became hair cells.

“We found that Notch directly suppresses differentiation (of support cells into hair cells), and indirectly inhibits proliferation by keeping Wnt in check,” Piotrowski explains. “Previously, others thought perhaps it was Wnt that had to be downregulated, to initiate regeneration. However, our data support the loss of Notch signaling as a more likely trigger.” Essentially, the process of restoring injured or dead hair cells in neuromasts is jump-started by the transient suppression of Notch, while its eventual reactivation restores the balance, ensuring that not all support cells answer the call to regenerate through proliferation and differentiation.

Piotrowski’s research is partially supported by the Hearing Health Foundation through its Hearing Restoration Project (HRP), which emphasizes collaborations across multiple institutions to develop new therapies for hearing loss. By continuing to illuminate the intricacies of hair cell regeneration in zebrafish, she and her team are providing other HRP scientists with candidate genes and molecular pathways to probe in other models such as chicken and mice, with the goal of providing insight that could someday make human inner ear hair cells readily replaceable.

The study was also funded by the Stowers Institute and the National Institute on Deafness and Other Communication Disorders of the National Institutes of Health (award RC1DC010631). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

Other Institute contributors include Joaquín Navajas Acedo; Linjia Jiang, Ph.D.; Agnė Kozlovskaja-Gumbrienė; Richard Alexander; and Hua Li, Ph.D.

Lay summary of findings

Hair cells in sensory structures called neuromasts, which form the sensory system fish use to orient themselves in water, are similar to mammalian inner ear hair cells responsible for our sense of hearing. Unlike the latter, however, they are constantly replaced after damage or death. In the current issue of Developmental Cell, Stowers Associate Investigator Tatjana Piotrowski, Ph.D., and members of her lab closely examine, in zebrafish, the support cells from which hair cells regenerate. By tracking individual support cells during neuromast regeneration, first author Andrés Romero-Carvajal, Ph.D., shows that approximately half become hair cells, while the rest self-renew as support cells. These lineage decisions are coordinated by interactions between the Notch and Wnt signaling pathways and are location-specific, as differentiation into hair cells occurs toward the center of neuromasts and self-renewal occurs at opposite poles of the structures. Piotrowski hopes her lab’s findings in zebrafish may be extrapolated to mammals someday, to help provide basic insight needed to progress towards the ultimate goal of regenerating human inner ear hair cells.

About the Stowers Institute for Medical Research

The Stowers Institute for Medical Research is a non-profit, basic biomedical research organization dedicated to improving human health by studying the fundamental processes of life. Jim Stowers, founder of American Century Investments, and his wife, Virginia, opened the Institute in 2000. Since then, the Institute has spent over one billion dollars in pursuit of its mission.

Currently, the Institute is home to almost 550 researchers and support personnel; over 20 independent research programs; and more than a dozen technology-development and core facilities.

The above post is reprinted, with permission, from materials provided by Stowers Institute for Medical Research.

Your financial support will help to ensure we can continue this vital research and find a cure in our lifetime! Please help us accelerate the pace of hearing and balance research and donate today. Your HELP is OUR hope!

If you have any questions about this research or our progress toward a cure for hearing loss and tinnitus, please contact Hearing Health Foundation at info@hhf.org.

URGENT: Demand Hearing Loss to be Acknowledged as a Disability

Recently, Hearing Health Foundation learned that the Centers for Disease Control and Prevention (CDC) conducted a study on the prevalence of disability in the U.S. The study examined vision loss, cognition, mobility, self-care and independent living, but failed to mention hearing loss, the third most common public health concern after diabetes and heart disease.

Hearing Health Foundation is outraged by this gross oversight and finds the exclusion of people living with hearing loss from the report to be a troubling concern. Failing to acknowledge hearing loss diminishes the fact that having a hearing loss is a concern worthy of attention and treatment, as well its impact on a person's quality of life, ability to work, and full participation in society.

Hearing Health Foundation is not sitting back quietly, and neither should you! We will be sending representatives at the White House and CDC a letter asking them to take swift and meaningful steps to correct this gross error, acknowledge hearing loss as a disability, and amend the report accordingly. 

If you would like to take action with HHF, please sign our petition on Change.org. You can also download this letter, sign and return it to us by e-mail or mail (Take Action, c/o Hearing Health Foundation, 363 7th Ave, NY, NY, 10001). We will be sending all letters on September 1st. 

If you have any questions or would like to share your own letter with us, please email us at info@hearinghealthfoundation.org.

Thank you,

Claire Schultz 

Chief Executive Officer 

Hearing Health Foundation

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2015 Emerging Research Grants Approved!

By Laura Friedman

Hearing Health Foundation is excited to announce that the 2015 Emerging Research Grants (ERG) have been approved by our Board of Directors, after a rigorous scientific review process. The areas that we are funding for the 2015 cycle are:

• Central Auditory Processing Disorder (CAPD): Four grants were awarded for innovative research that will increase our understanding of the causes, diagnosis, and treatment of central auditory processing disorder, an umbrella term for a variety of disorders that affect the way the brain processes auditory information. All four of our CAPD grantees are General Grand Chapter Royal Arch Masons International award recipients.
  

• Hyperacusis: Two grants were awarded that is focused on innovative research (e.g., animal models, brain imaging, biomarkers, electrophysiology) that will increase our understanding of the mechanisms, causes, diagnosis, and treatments of hyperacusis and severe forms of loudness intolerance. Research that explores distinctions between hyperacusis and tinnitus is of special interest. Both of our Hyperacusis grants were funded by Hyperacuis Research.
  

• Ménière’s Disease: Two grants were awarded for innovative research that will increase our understanding of the inner ear and balance disorder Ménière’s disease. One of the grants is funded by The Estate of Howard F. Schum and the other is funded by William Randolph Hearst Foundation through their William Randolph Hearst Endowed Otologic Fellowship.
  

• Tinnitus: Two grants were awarded for innovative research that will increase our understanding of the mechanisms, causes, diagnosis, and treatment of tinnitus. One of the grants is funded by the Les Paul Foundation and the other grantee is the recipient of The Todd M. Bader Research Grant of The Barbara Epstein Foundation, Inc.

To learn more about our 2015 ERG grantees and their research proposals and goals, please visit: http://hearinghealthfoundation.org/2015_researchers

Hearing Health Foundation is also currently planning for our 2016 ERG grant cycle. If you're interested in naming a research grant in any discipline within the hearing and balance space, please contact development@hhf.org.

Rare Gene Cariant Associated with Middle Ear Infections

By Baylor College of Medicine

Many parents have heard the night-time cry of “my ear hurts.” For some children, this might happen frequently beginning in infancy and even persist into adulthood. An international consortium led by those at Baylor College of Medicine may have taken the first step on the road to understanding why only some people get frequent painful or chronic middle ear infections. The culprit may be rare genetic variants in a gene called A2ML1.

A report on their work appears online in the journal Nature Genetics.

In studies led by Dr. Regie Lyn P. Santos-Cortez, assistant professor of molecular and human genetics at Baylor, researchers looked for a genetic component to the disorder. Santos-Cortez is not only a genetics researcher, she was also trained as an otolaryngologist in her native Philippines, and she knows the toll such infections take.

After graduation, she went on a medical missionary trip to an indigenous Filipino population in one area of the country where most of the people were related.

There she created a family tree or pedigree that identified, among other things, who within the same community suffered from recurrent ear infections and who did not.

“The pedigree was huge,” she said. “It was several pages long and wide.”

Everyone had similar socioeconomic status, swam in the same sea water, were or had been mostly breastfed, ate the same food, and had the same exposure to cigarette smoke, which made an environmental factor an unlikely cause.

Luckily, next-generation sequencing that allowed her to determine the genetic sequence of several people in the population was available. Without that technological advance, she said, she did not think they could have identified the gene.

Within the indigenous community, she found that 80 percent of those who carry the variant in the A2ML1 gene developed otitis media. They also found the same gene variant in three otitis-prone children in a group in Galveston, Texas.

So far, they have identified this rare genetic cause for susceptibility to middle ear infections in 37 Filipinos, one Hispanic-American and two European-Americans. It is likely that the variant has been present in the population in the Philippines and in Galveston at least 150 years and may even be the result of a “founder” effect, which suggests one person from outside the population, more likely from Spain, brought the gene variant into the two populations.

Additionally, rare A2ML1 variants were identified in six otitis-prone children who were Hispanic- or European-American, and none of these variants occurred in thousands of individuals without otitis media.

She does not think this is the only gene involved in predisposing children to middle ear infections, but it could be an important one. The protein involved may play a role in the immune system that protects the ear. Perhaps the variant somehow derails the protection the protein should provide.

Another gene called alpha 2-macroglobulin or A2M, which encodes a protein that is found at high levels in very infected ears, is formed in such a way that it can trap proteases, enzymes that can kill infectious microbes but can also damage the mucosa of the middle ear if left unchecked.

Because the protein sequences of A2M and A2ML1 are highly identical, they may have similar or overlapping functions and one might compensate for the other when it is non-functional. An antibiotic drug called bacitracin is used in drop form to treat the problem in Europe. However, because bacitracin dampens the effect of A2M it may not be the best treatment for people who have genetic variants in A2ML1, she said.

“There are many other antibiotic drops on the market,” said Santos-Cortez.

The finding of the variant is a start, she said. She and her colleagues hope to look further into the mechanism by which A2ML1 defects cause otitis media susceptibility.

Others who took part in this work include Xin Wang, Anushree Acharya, Izoduwa Abbe, Biao Li, Gao T. Wang and Suzanne M. Leal, all of Baylor; Charlotte M. Chiong, Ma Rina T Reyes-Quintos, Ma Leah C. Tantoco, Marieflor Cristy Garcia, Erasmo Gonzalo D V Llanes, Patrick John Labra, Teresa Luisa I. Gloria-Cruz, Abner L. Chan, Eva Maria Cutiongco-de la Paz and Generoso T. Abes, all of the University of the Philippines Manila-National Institutes of Health; Arnaud P. Giese, Saima Riazuddin and Zubair M. Ahmed, University of Maryland at Baltimore; Joshua D Smith, Jay Shendure, Michael J. Bamshad and Deborah A. Nickerson, all of the University of Washington at Seattle; E. Kaitlynn Allen and Michele M. Sale of the University of Virginia in Charlottesville; Kathleen A. Daly of the University of Minnesota in Minneapolis; Janak A. Patel and Tasnee Chonmaitree of the University of Texas Medical Branch at Galveston.

Funding for this work came from the Hearing Health Foundation; Action On Hearing Loss and the National Organization for Hearing Research Foundation (to R.L.P.S.-C.); the University of the Philippines Manila–National Institutes of Health (to G.T.A. and R.L.P.S.-C.); and U.S. National Institutes of Health (Grants U54 HG006493 (to D.A.N.), R01 DK084350 (to M.M.S.), R01 DC003166 (to K.A.D.), R01 DC005841 (to T.C.), R01 DC011803 and R01 DC012564 (to S.R. and Z.M.A.), and R01 DC011651 and R01 DC003594 (to S.M.L.).

The above post is reprinted from materials provided by Baylor College of Medicine.

Help us change the course of hearing research and find a cure for hearing loss and tinnitus! Hearing Health Foundation’s “Name a Research Grant” program enables donors to name and fund a specific research grant in their name or in honor or memory of a loved one.

We're currently planning for our 2016 grant cycle. If you're interested in naming a research grant in any discipline within the hearing and balance space, such as Usher Syndrome, hyperacusis, stria, or tinnitus, please contact development@hhf.org. 

Life-Saving Antibiotics Increase Risk of Hearing Loss

By Oregon Health & Science University

Approximately 80% of infants in neonatal intensive care units receive antibiotics known to be toxic to the ear. 

Seeking to stem the tide of permanent hearing loss from the use of life saving antibiotics, researchers at Oregon Health & Science University have found that patients stricken with dangerous bacterial infections are at greater risk of hearing loss than previously recognized. Inflammation from the bacterial infections substantially increased susceptibility to hearing impairment by increasing the uptake of aminoglycoside antibiotics into the inner ear, the researchers report. Their findings are published in online in the journal Science-Translational Medicine.

“Currently, it’s accepted that the price that some patients have to pay for surviving a life-threatening bacterial infection is the loss of their ability to hear. We must swiftly bring to clinics everywhere effective alternatives for treating life-threatening infections that do not sacrifice patients’ ability to hear,” said Peter S. Steyger, Ph.D.*, professor of otolaryngology, head and neck surgery, Oregon Hearing Research Center, Oregon Health & Science University School of Medicine. “Most instances in which patients are treated with aminoglycosides involve infants with life-threatening infections. The costs of this incalculable loss are borne by patients and society. When infants lose their hearing, they begin a long and arduous process to learn to listen and speak. This can interfere with their educational trajectory and psychosocial development, all of which can have a dramatic impact on their future employability, income and quality of life.”

Aminoglycosides, antimicrobials that are indispensable to treating life-threatening bacterial infections, are toxic to the ear. Relied on by physicians to treat meningitis, bacteremia and respiratory infections in cystic fibrosis, aminoglycosides kill the sensory cells in the inner ear that detect sound and motion.

Infants in neonatal intensive care units, or NICUs, are at particular risk. Each year, approximately 80 percent of 600,000 admissions into NICUs in the United States receive aminoglycosides. The rate of hearing loss in NICU graduates is 2 to 4 percent compared with 0.1 to 0.3 percent of full-term births from congenital causes of hearing loss.

When Steyger and colleagues gave healthy mice a low amount of aminoglycoside, the rodents experienced a small degree of hearing loss. If the mice had an inflammation that is typical of the infections treated with aminoglycosides in humans, the mice experienced a vastly greater degree of hearing loss.

The study lays the groundwork for improving the standard of care guidelines for patients receiving aminoglycosides. To shield patients’ hearing, the researchers called for the development of more targeted aminoglycosides and urged clinicians to choose more targeted, non-ototoxic antibiotics or anti-infective drugs to treat patients stricken with severe infections.

Due to their widespread availability and low cost, aminoglycosides are used frequently worldwide. Clinical use of aminoglycosides is limited due to the known risk of acute kidney poisoning and permanent hearing loss, yet are crucial life-savers in cases with potentially fatal infections.

Scientists who contributed to the OHSU study, “Endotoxemia-mediated inflammation potentiates aminoglycoside-induced ototoxicity,” include: Steyger; Ja-won Koo, M.D., Ph.D.; Lourdes Quintanilla-Dieck, M.D.; Meiyan Jiang, Ph.D.; Jianping Liu, M.D., Ph.D.; Zachary D. Urdang, B.S.; Jordan Allensworth, B.S.; Campbell P. Cross, B.A.; and Hongzhe Li, Ph.D.

This research was supported by: National Research Foundation of Korea grant 2011-0010166; Seoul National University Bundang Hospital 03-2011-007 (J.K.W.); National Institute of Deafness and Other Communication Disorders R01 DC004555, R01 DC12588 (P.S.S.), R03 DC011622 (H.L.), and P30 DC005983; and the Department of Otolaryngology at OHSU (L.Q.D.).

*Peter S. Steyger, Ph.D., is a prior Hearing Health Foundation board member and previous head of our Council of Scientific Trustees.

The above post is reprinted from materials provided by Oregon Health & Science University.

Ask the Scientist: Gene Therapies and Hearing

By Peter G. Barr-Gillespie, Ph.D.

A DNA double helix

National Human Genome Research Institute

Recently, Hearing Health Foundation (HHF) has received several questions regarding the Reuters report on gene therapies for hearing. There are two separate but related topics raised in this article. As the scientific research director of HHF’s Hearing Restoration Project, which since 2011 has been uncovering concrete discoveries toward a biologic cure for hearing loss and tinnitus, I want talk about each individually, and then discuss what I interpret they mean together.

The article first presents the Science Translational Medicine paper from Jeffrey Holt’s lab. This is very much a proof-of-principle report, focused on an animal model and using a time for delivery of the corrected gene that is extremely early in development (equivalent to a 5-to-6-month-old human fetus). It is important to point out that their strategy will only correct one type of genetic hearing loss and genetic hearing loss from mutations in other genes will require related but different strategies. Nevertheless, this is an exciting example of modeling gene therapy in animals, and represents a logical progression toward that goal in humans.

The article then moves on to reference the Novartis trial. For this trial, they are using a similar technical strategy, viral delivery of a gene, but they are targeting people—those who have lost their hearing through non-genetic means, such as noise damage, aging, or infections. The gene they are delivering, known as ATOH1, may stimulate production of new hair cells; it is a gene that is essential for formation of hair cells during development, and in some experimental animal models, delivery of the gene can lead to production of a few hair cells in adult ears.

That said, many people who I have talked to in the field who work with experimental models of hair cell formation using ATOH1, including members of our Hearing Restoration Project consortium, believe that this trial is premature. By and large, the animal models do not support the trial; most suggest that there will be few hair cells formed and little hearing restored. While we can hope for a little bit of hearing recovery, we are concerned about toxic responses to the gene delivery using viruses. Personally, while I think it would be truly fantastic if the Novartis trial works, at this moment in time I don’t think the rewards yet outweigh the considerable risks being imposed on a human (include safety during the procedure and potential side effects afterward).

Still, the Novartis trial will tell us about the safety of viral delivery into the ears of humans, and knowing that is critically important. I think the most likely outcome is that we will learn whether the strategy the Novartis trial used to deliver the gene is safe. Unfortunately, if we don’t see improved hearing, we won’t know why—did the gene not get to the right place, or does it just not work?

Technical aspects of gene delivery are what ties together the Novartis work and the Holt lab work. Both use viruses for delivering genes, and together the results from these and others will let us know, from a procedural standpoint, how we can deliver genes to the ear. I think it is unlikely that delivering just ATOH1 will do the trick of restoring hearing; it may be that we need to deliver other genes or to use drugs to overcome the block we see to making new hair cells.

So while these are exciting reports to hear about, especially that Novartis is actually carrying out a trial in humans, it is still premature to think that this is going to be a viable strategy for restoring hearing. This is why Hearing Health Foundation's Hearing Restoration Project is doing everything possible to accelerate the pace of its research.

Hair cell regeneration is a plausible goal for the treatment of hearing and balance disorders. The question is not if we will regenerate hair cells in humans, but when. Your financial support will help to ensure we can continue this vital research and find a cure in our lifetime! Please help us accelerate the pace of hearing and balance research and donate today. Your HELP is OUR hope!

If you have any questions about this research or our progress toward a cure for hearing loss and tinnitus, please contact Hearing Health Foundation at info@hhf.org.

I Lost My Hearing in My Forties. Here's How I Handled It.

By Mary Louise Kelly

The interesting thing about going deaf is you don’t realize it’s happening. It’s impossible to pinpoint when everyone began to mumble, when you ceased hearing your own footsteps clicking down a hall.

“Is it the accents?” my husband asked when I complained that the actors on Downton Abbey spoke too fast. We started watching with subtitles. At the theater, I focused on the beauty of the sets and costumes because—though I would have denied this—I couldn’t follow the dialogue. Meanwhile, car horns and sirens dimmed. Packages didn’t arrive, yet the UPS man insisted he’d rung the bell three times. “Impossible,” I shot back. “I was home.”

My lowest moment came last spring at a reading to promote my first novel. A woman rose and recounted what I later learned was a risqué tale about a CIA spy (the book was an espionage thriller), then asked a question that had the audience in stitches. I squirmed, laughed along, and responded with what was surely a non sequitur, as I’d caught barely a word of what she’d said. In the taxi home, I thought: Enough.

Still, none of this prepared me for sitting in an audiologist’s office at age 43, being told that I suffered severe hearing loss. How severe? In one test, he stood across the room, spoke a series of words in a normal voice, and asked me to repeat them.

“Void,” he said.

“Void,” I repeated.

“Ditch,” he said.

“Ditch.”

Out of 20, I got 16. “Not perfect,” I sniffed, “but hardly severe.”

He repeated the test, now holding a sheet of paper before his face.

“Mumble,” he said.

“Um . . . repeat that one?”

“Mumble mumble.”

“Shoelace?”     

“Nope. Mumbledy mumble.”

This time, I got 6 out of 20. When I couldn’t see his lips move, I missed 70 percent of what he said. 

“How are you even functioning?” he inquired, genuinely mystified.

As a reporter, I’ve spent time on aircraft carriers, in helicopters, in war zones. For two decades, I’ve edited stories on deadline through headphones cranked too loud. But the most likely explanation for my hearing loss? Genetics. My father is hard of hearing. So are his sisters and 96-year-old mother. I’ve long known what loomed in my future—I just hadn’t expected it so early.

My first day with hearing aids, I went about my routine with a sense of wonder. It was astonishing to rediscover that pop songs had words I could sing along to. “Have been bopping to an ’80s dance mix all morning,” I posted on Facebook. “I challenge anyone to deny Debbie Gibson was a genius ahead of her time.” (To which came the inevitable reply: “You need to get your hearing checked.”)

By day two, I was on sensory overload. Starbucks left me near tears—I’d had no idea frothing milk made such a racket. I jogged in Rock Creek Park and for the first time in years didn’t jump every time cyclists whizzed past, because I could hear them coming.

The doctors can’t say whether my hearing has stabilized or will worsen. And hearing aids are an imperfect solution. The experience is different from, say, getting glasses and instantly being able to see. It takes time for the brain to adjust, to relearn the pathways it once knew. You almost never recover all that has been lost.

But you do learn to savor small triumphs. The other day, the UPS driver rang my doorbell and I heard him—and tipped big. I still can’t watch TV without subtitles. But at a play recently, the curtain rose and I slumped in sheer relief at being able to follow the words. Not every line, but enough. I’m holding onto that theater program, a memento of a pleasure once dimmed, now mine once more.

Mary Louise Kelly is a contributing editor at The Atlantic. She has spent two decades reporting on national security and international affairs for NPR and the BBC. As NPR’s intelligence and defense correspondent, she covered wars, terrorism, and rising nuclear powers. Kelly has also anchored NPR programs including “Morning Edition” and “All Things Considered.” She has taught national security and journalism at Georgetown University. Kelly’s writing has appeared in The New York Times, The Washington Post, Newsweek, Politico, and others. She is the author of two novels: Anonymous Sources and The Bullet.

Taking Hair Cell Regeneration Down a Notch

By Andy Groves

Hearing Restoration Project (HRP) consortium scientists, Andy Groves and Stefan Heller had their research published in Frontiers in Cellular Neuroscience on March 31, 2015. Below is a summary of their research:

Sensorineural hearing loss is most commonly caused by the death of hair cells in the organ of Corti, and once lost, mammalian hair cells do not regenerate. In contrast, other vertebrates such as birds can regenerate hair cells by stimulating division and differentiation of neighboring supporting cells.

During the development of the inner ear, newly-born hair cells send signals to their neighbors that instruct them to not become hair cells, but to become supporting cells instead. Hair cells are the mechanosensitive cells of the ear. Supporting cells surround them and as their name implies, physically support them and help regulate some of the properties of hair cells. One of these signals is an evolutionarily ancient pathway, the Notch signaling pathway. We and others have shown that if you block the Notch signaling pathway in the cochlea or balance organs of young mice, the supporting cells no longer get the message to stay as supporting cells, and instead they transform into hair cells. This process also happens during hair cell regeneration in birds - supporting cells transform into hair cells, which then send a Notch signal to their neighbors and prevent too many hair cells from being formed.

These observations suggest that it might be possible to block Notch signaling in mature, deafened animals as a means of getting new hair cells to form. We performed a simple experiment to test this in progressively older and older animals. To our surprise, we found that once mice are more than a week old, blocking Notch signaling has no effect on the cochlea any more, and no new hair cells are made.  We showed that this was due in part to components of the Notch signaling pathway being switched off in the ear as the animals get older. Viewed this way, the Notch signaling pathway can be thought of as a “Scaffold” - it is used to allow the cochlea to be built in the first place, but is then dismantled once the cochlea becomes functional.

What does this mean? It suggests that inhibiting Notch signaling alone is unlikely to be an effective means of hair cell regeneration in mammals. It is possible that other factors will be required, and some HRP members are busy testing these other pathways right now. It will also be of great interest to understand HOW the Notch pathway is dismantled with age, whether we can exploit this in future therapies.

Read more about this research proposal here: http://hearinghealthfoundation.org/hrp-consortium-projects-groves-segil-stone.

This work was supported by Department of Defense Grant DODW81XWH-11-2-004(AKG) and Hearing Restoration Project consortium grants from the Hearing Health Foundation (AKG and SH), NIH grant DC004563 (SH), NIH grant P30DC010363 (SH, JSO), and NIHR01DC014450 (JSO).

Hair cell regeneration is a plausible goal for the treatment of hearing and balance disorders. The question is not if we will regenerate hair cells in humans, but when. Your financial support will help to ensure we can continue this vital research and find a cure in our lifetime! Please help us accelerate the pace of hearing and balance research and donate today. Your HELP is OUR hope!

If you have any questions about this research or our progress toward a cure for hearing loss and tinnitus, please contact Hearing Health Foundation at info@hhf.org.