Tinnitus

Outsmarting the Most Common Military Injury: How One Veteran Is Helping Future Generations

By Imani Rodriguez

After 26 years of military service, Hearing Health Foundation (HHF) Board Chair Col. John Dillard (U.S. Army, Ret.) lives with tinnitus and noise-induced hearing loss. Tinnitus is one of the most prevalent war injuries among American veterans—and hearing loss is equally common—and Dillard is dedicated to improving the lives of millions through the advancement of tinnitus research that will lead to more reliable treatments and, eventually, permanent relief through cures. Tinnitus is the perception of ringing or buzzing in the ears without an external sound source.

In addition to supporting the advancement of more viable treatments and cures for tinnitus through HHF’s groundbreaking research, Dillard is a U.S. Department of Defense consumer reviewer for the Peer Review Medical Research Program (PRMRP), part of the U.S. government’s Congressionally Directed Medical Research Programs. 

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Dillard is actively serving as a tinnitus consumer reviewer for the fourth consecutive year after again meeting qualifications through a rigorous application process. As a senior lecturer for systems acquisition management at the Naval Postgraduate School in Monterey, California, he is well connected with members of the military community, many who also live with tinnitus. He is a valuable contributor to discussions about tinnitus with scientists and the general public alike.

As a tinnitus consumer reviewer for the PRMRP, Dillard is responsible for evaluating and scoring tinnitus research proposals based on their potential for scientific and clinical impact. His academic experience as a military researcher has allowed him to assist with the critical thinking and reasoning aspects of each proposal. And from his own military experience, Dillard is keenly aware of how vital this research is for those returning from combat.

Tinnitus is a chronic condition without an existing reliable treatment, although certain products on the market claim otherwise. “There are no nutritional, pharmacological, surgical, deep brain or transdermal electrical stimulation, sound, transcranial magnetic, or other therapies proven efficacious for tinnitus,” Dillard says. “There are many treatments marketed to the naive consumer or patient/sufferer, but none of them are truly effective. Most folks who know me understand my extreme cautions against what I consider ‘snake oil’ treatments. People should spend no money on these products.”

Dillard says one exception using sound therapy is Tinnitus Retraining Therapy (TRT), currently considered the gold standard in coping with—but not eliminating or curing—disruptive levels of tinnitus. “I have personally benefited from TRT,” he says. TRT involves wearing ear-level devices that work to deliver masking noise to the brain, with or without hearing amplification; the therapy can typically be incorporated into hearing aids. 

Dillard is confident progress will continue to be made by both HHF and the Department of Defense. “We know now that tinnitus is more of a ‘brain problem’ that usually starts from damage to the ear in the form of noise-induced hearing loss,” he says. 

“We need to help the brain heal itself and correct what is actually an auditory ‘hallucination’ of hyperactive neuronal activity. It’s a very resilient, maladaptive feedback loop that works much like learned pain,” Dillard adds “We also hope for various pharmacological approaches being tried that can help tamp down this hyperactivity. I’m hopeful that we will see progress on treating tinnitus in our lifetimes.”

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Col. John Dillard (U.S. Army, Ret.) was appointed Chair of Hearing Health Foundation’s Board of Directors July 1, 2019, after joining the Board in February 2018. He wrote about his experience in the military and how it affected his hearing as the Fall 2017 Hearing Health cover story. HHF marketing and communications intern Imani Rodriguez studied communications and public relations at Rutgers University. 

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2019-2020 Emerging Research Grantees Announced

By Christopher Geissler, Ph.D.

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Hearing Health Foundation (HHF) is proud to announce the recipients of Emerging Research Grants (ERG) for the upcoming year (July 1, 2019 — June 30, 2020). Following a rigorous review process, our Scientific Review Committee and Council of Scientific Trustees, comprised of senior expert scientists and physicians from across the US, have chosen fourteen especially meritorious projects to fund, covering a broad range of hearing and balance science. We are pleased to be able to support the work of these promising researchers and look forward to learning about the advances they will undoubtedly make in the coming year and beyond.

This year’s ERG recipients are:

Dunia Abdul-Aziz, M.D.
Massachusetts Eye and Ear
Project: Targeting epigenetics to restore hair cells

Pierre Apostolides, Ph.D.
Regents of the University of Michigan
Project: Novel mechanisms of cortical neuromodulation

Michael Dent, Ph.D.
University at Buffalo
Project: Noise-induced tinnitus in mice
Generously funded by The Les Paul Foundation

Vijayalakshmi Easwar, Ph.D.
University of Wisconsin Madison
Project: Neural correlates of amplified speech in children with sensorineural hearing loss
Generously funded by The Children’s Hearing Institute

Kristi Hendrickson, Ph.D.
University of Iowa
Project: Neural correlates of semantic structure in children who are hard of hearing
Generously funded by General Grand Chapter Royal Arch Masons

Hao Luo, Ph.D.
Wayne State University
Cochlear electrical stimulation induced tinnitus suppression and related neural activity change in the rat's inferior colliculus
Generously funded by General Grand Chapter Royal Arch Masons

Kristy Lawton, Ph.D.
Washington State University Vancouver
Project: Characterizing noise-induced synaptic loss in the zebrafish lateral line
Generously funded by General Grand Chapter Royal Arch Masons

Anat Lubetzky, P.T., Ph.D.
New York University
Project: A balancing act in hearing and vestibular loss: assessing auditory contribution to multisensory integration for postural control in an immersive virtual environment

David Martinelli, Ph.D.
University of Connecticut Health Center
Project: Creation and validation of a novel genetically-induced animal model for hyperacusis
Generously funded by Hyperacusis Research

Jameson Mattingly, M.D.
The Ohio State University
Project: Differentiating Ménière's disease and vestibular migraine using audiometry and vestibular threshold measurements

Vijaya Prakash Krishnan Muthaiah, P.T., Ph.D.
University at Buffalo
Project: Potential of inhibition of Poly ADP Ribose Polymerase as a therapeutic approach in blast induced cochlear and brain injury.
Generously funded by General Grand Chapter Royal Arch Masons

William “Jason” Riggs, Au.D.
The Ohio State University
Project: electrophysiological characteristics in children with auditory neuropathy spectrum disorder
Generously funded by General Grand Chapter Royal Arch Masons

Gail Seigel, Ph.D.
The Research Foundation of SUNY on behalf of the University at Buffalo
Project: Targeting microglial activation in hyperacusis

Victor Wong, Ph.D.
Burke Medical Research Institute
Project: Targeting tubulin acetylation in spiral ganglion neurons for the treatment of hearing loss

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Very High-Frequency Hearing Loss and Tinnitus: Is There a Link?

By Julia Campbell, Au.D., Ph.D.

Tinnitus is theorized to possibly arise from decreased central inhibition related to cochlear damage, or hearing loss. A reduction in inhibition function would allow signals that are normally suppressed to be perceived, resulting in tinnitus. However, many individuals with clinically typical hearing also present with tinnitus.

In our earlier study, results indicated that despite an apparently intact peripheral auditory system, inhibitory function was atypical and significantly related to tinnitus severity among a population reporting mild tinnitus. With central inhibition lowered, signals that are typically dampened are able to be perceived, potentially resulting in tinnitus. Our paper also showed the utility of measuring central inhibition through cortical auditory evoked potentials (CAEPs), which are electrical responses in the brain that reveal levels of central inhibition.

Given the prior study’s results, we thought it is possible that hearing loss within extended high-frequency thresholds (10, 12.5, and 16 kilohertz), which are not typically assessed in the clinic, may negatively impact inhibitory function and subsequent gating measures.

For our follow-up research, published in the American Journal of Audiology on April 22, 2019, we examined the role of both extended high-frequency thresholds and sensory gating dysfunction, a measure of central inhibition abnormality, in typical-hearing adults with and without tinnitus. Results suggest that extended high-frequency thresholds do not correlate with CAEP amplitude gating indices—in other words, high-frequency hearing loss was not associated with decreased central inhibition.

CAEP gating waveforms in A) a typical-hearing subject without tinnitus and B) a typical-hearing subject with tinnitus. The solid line represents the CAEP response to the first stimulus (S1) in a tonal pair, and the dashed the CAEP response to the second stimulus (S2) in a tonal pair. Typical gating is observed when CAEP S2 amplitude is lower compared with CAEP S1 amplitude (A). Atypical gating occurs when CAEP S2 amplitude is equal to or larger than CAEP S1 amplitude (B).

CAEP gating waveforms in A) a typical-hearing subject without tinnitus and B) a typical-hearing subject with tinnitus. The solid line represents the CAEP response to the first stimulus (S1) in a tonal pair, and the dashed the CAEP response to the second stimulus (S2) in a tonal pair. Typical gating is observed when CAEP S2 amplitude is lower compared with CAEP S1 amplitude (A). Atypical gating occurs when CAEP S2 amplitude is equal to or larger than CAEP S1 amplitude (B).

However, we found an unexpected relationship in the tinnitus group: Those with better (lower) thresholds also presented with worse tinnitus. We believe this finding may be due to typical-hearing adults with better high-frequency hearing to be more aware of internal auditory signals, and thus perceive tinnitus. However, further research is needed to investigate this hypothesis.

In addition, atypical gating performance was observed in adults with a Tinnitus Handicap Inventory score over 6, which may demonstrate that tinnitus severity must reach a certain point in order for central gating deficits to be observed, or vice versa. A hierarchical multiple regression showed both extended high-frequency thresholds and atypical gating function to account for a significant 49 percent of tinnitus severity.

Therefore, auditory gating appears to be a useful objective measure for tinnitus severity, at least in adults with clinically typical hearing. It also appears that the testing of extended high-frequency thresholds is warranted in this population, to be used in combination with CAEP amplitude gating indices. Our laboratory is now conducting studies investigating the utility of auditory gating as a clinical tool for the objective assessment of tinnitus severity in adults with hearing loss.

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2016 Emerging Research Grants scientist Julia Campbell, Au.D., Ph.D., CCC-A, FAAA, received the Les Paul Foundation Award for Tinnitus Research. She is an assistant professor in communication sciences and disorders in the Central Sensory Processes Laboratory at the University of Texas at Austin. If you are interested in participating in this research, email julia.campbell@austin.utexas.edu.

Empower groundbreaking research toward better treatments and cures for hearing loss and tinnitus. If you are able, please make a contribution today.

 
 
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Stenting to Relieve One Specific Cause of Pulsatile Tinnitus

By Jayne Wallace for the Weill Cornell Medicine Brain and Spine Center

The Centers for Disease Control and Prevention estimates that 15 percent of the U.S. population, or 48 million people, have some type of tinnitus, hearing a ringing or buzzing in the absence of an external sound source.

Pulsatile tinnitus, in contrast, usually has a sound source. In these cases, affecting fewer than 10 percent of tinnitus patients, sounds are caused by turbulence in the blood flow around the ear. And among these cases, intracranial hypertension comprises about 8 percent of cases. This is when narrowing in one of the large veins in the brain causes a disturbance in the blood flow, leading to the pulsatile tinnitus.

Dural arteriovenous fistula, MRA showed only subtle alterations as a result of atypical flows in the right transverse sinus (arrow). Photo courtesy of Deutsches Ärzteblatt International.

Dural arteriovenous fistula, MRA showed only subtle alterations as a result of atypical flows in the right transverse sinus (arrow). Photo courtesy of Deutsches Ärzteblatt International.

“Traditionally there has been no good treatment for many of these patients who are told to learn to live with it,” says Athos Patsalides, M.D., an interventional neuroradiologist at New York City’s Weill Cornell Medicine Brain and Spine Center, where he also serves as an associate professor of radiology in neurological surgery.

Till now, available treatments—medication or more complicated surgery—were either ineffective or produced side effects and other problems just as bad or worse. “That’s why we started the clinical trials for venous sinus stenting, a minimally invasive procedure that is very effective in alleviating the narrowing in the vein,” says Patsalides, who pioneered the use of VSS to treat patients with idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri because the symptoms tend to mirror those of a brain tumor.

“Many IIH patients suffer from vision loss, headaches, and pulsatile tinnitus, and I saw a pattern with patients experiencing resolution of the pulsatile tinnitus immediately after VSS,” Patsalides says.

This led to the possibility of using VSS for selected patients with pulsatile tinnitus. After the Food and Drug Administration approved the clinical trial, it began in May 2016 and has an estimated completion date of January 2021.

“In the stenting procedure, with the patient under general anesthesia, we insert a tiny, soft catheter into a vein located in the upper part of the leg and thread it up to the affected vein in the brain,” Patsalides says.

A self-expanding stent is deployed into the narrowed segment of the vein, relieving the stenosis, restoring normal blood flow, and reducing or eliminating the pulsatile tinnitus. “Happily, the patient is typically discharged from the hospital within 24 to 48 hours,” he says.

To learn more, see weillcornellbrainandspine.org. Hearing Health Foundation notes that the trial is ongoing, and that the procedure is potentially able to address only one specific cause of pulsatile tinnitus and should not be taken as a solution for other forms of tinnitus, which often has no known cause.

You can empower work toward better treatments and cures for hearing loss and tinnitus. If you are able, please make a contribution today.

 
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The Strength of Our Olympians

By Vicky Chan

The competitors in this year’s Winter Olympics are full of drive and determination. Olympians throughout history have overcome various challenges for a chance to win the gold, including hearing loss. Hearing loss has played a big role in the lives of some Olympians. In spite of their disability, or, perhaps, because of it, hard-of-hearing Olympians have thrived as athletes. Rather than viewing their hearing loss as a limitation, these Olympians—our very own Gold Medalists—have claimed that compromised hearing has shaped their work ethics and contributed to their success.

Adam Rippon

American Figure skater Adam Rippon. Credit:    Jim Gensheimer/Bay Area News Group.

American Figure skater Adam Rippon. Credit: Jim Gensheimer/Bay Area News Group.

Adam Rippon is a figure skater participating in the 2018 Olympics. He was born with an eye infection and 80% hearing loss. Before his first birthday, he had major surgeries to correct both issues. At age 5, he survived a bursted appendix and severe respiratory condition. Despite his early health difficulties, he won a gold medal at the Four Continent Championship and the national title in 2016.

Tamika Catchings

Tamika Catchings is a retired American WNBA star who was born with hearing loss. She participated in more than 15 WNBA seasons and won four Olympic Gold Medals. Catchings has attributed her success to her hearing loss—compared to her typical-hearing opponents, she is more observant on court which allows her to react faster than they can. Catchings said, “As a young child, I remember being teased for...my big, clunky hearing aids, and the speech problems...Every day was a challenge for me...I outworked [the kids who made fun of me], plain and simple.”

Frank Bartolillo

Frank Bartolillo is an Australian fencer who competed in the 2004 Olympics. He was born with hearing loss, but Bartolillo states that his hearing loss has actually helped him improve his fencing skills by allowing him to fully focus on his opponent.

Carlo Orlandi

Carlo Orlandi was an Italian boxer. At age 18, Orlandi became the first deaf athlete to compete and win a Gold Medal in the 1928 Olympics. Later, he became a professional boxer with a career that spanned 15 years and won nearly 100 matches.

David Smith

David Smith is an American volleyball player who was born with severe hearing loss. At age three, he was fitted for hearing aids in both ears. As an athlete, he relies heavily on hand signals and lip reading to communicate with his teammates. On the court, Smith can’t wear his hearing aid, so his coach, John Speraw, uses the “David Smith Rule.” This rule mandates that “when David wants it, David takes it,'" says Speraw. "Because in the middle of a play, you can't call him off...He's mitigated any issues he has by being a great all-around volleyball player."

Chris Colwill

Chris Colwill is an American diver who was born with hearing loss. Although his hearing aid allows him to hear at an 85-90% level, he can not use it while diving and relies on the scoreboard for his cue to dive. But Colwill stated that this is an advantage for him—noise from the crowd doesn’t distract his concentration on diving.

Katherine Merry

Katherine Merry is a former English sprinter who won a Bronze Medal in the 2000 Olympics. At age 30, she developed tinnitus when a nurse made a mistake during a routine ear cleaning procedure. Ever since, she has lived with a constant high-pitch buzzing sound in her ears. It becomes worse when she is tired, overworked or on a flight. Today, Merry works as a BBC Sports Presenter.

These Olympians prove that those affected by hearing loss can pursue successful careers in sports. Refusing to let anything hold them back, they turned their disabilities into advantages in their respective competitions. Hearing loss allows them to block out distractions and focus on the sport. Their disability has shaped their determination, forcing them to become stronger and better athletes.

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HHF Launches Faces of Hearing Loss Campaign

Think of someone you know who has hearing loss. Who do you see?

You envision a relative, but you are not thinking of your 4-year-old niece. A neighbor comes to mind, but not the 32-year-old who lives across the street.

This is a trick question. Hearing loss—and related conditions like tinnitus, Ménière's disease, and hyperacusis—can affect anyone, anywhere. Hearing loss is your 4-year-old niece, your 32-year-old neighbor, your colleague in her mid-20s. Hearing loss affects every age, race, ethnicity, and gender.

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No one is immune from developing a hearing and balance disorder—and hearing loss has no single face. To refute common misconceptions that it only affects older adults, HHF has collected images of individuals living with a hearing condition to capture the diversity of its impact across the country. These are HHF’s “Faces of Hearing Loss.”

Participants shared their picture, current age, state of residence, type of hearing condition, and the age at onset or diagnosis. Among the tens of millions of Americans with hearing loss are an 11-year-old boy in Oregon, an 80-year-old woman living in Washington, and a 47-year-old man in North Dakota. These individuals may never meet, but “Faces of Hearing Loss” connects them through their shared experiences.

If you or a loved one has hearing loss, please consider participating in “Faces of Hearing Loss” by completing this brief form, sending in picture, and answering a few basic questions. If you are the parent of a child under 18, you may sign a release form on their behalf.

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One Man's Military Perspective

By Colonel John T. Dillard, U.S. Army (Retired)

The top two disabilities for our returning veterans from Iraq and Afghanistan are hearing loss and tinnitus, or ringing of the ears (which is actually a sound inside the brain). Both conditions became a problem for me and for many of my friends in the service. A lifetime spent in the U.S. Army, starting in the 1970s, meant frequent exposure to gunfire and proximity to screaming jets and helicopter engines.

Even during a peacetime career in the military, our soldiers, sailors, airmen, and marines are subject to a barrage of auditory insults from the weapons and equipment they operate. It all stacks up to a gradual, although sometimes very abrupt, loss of hearing, usually starting at the higher frequencies. For those in the service, any age-related decline in hearing gets accelerated, to the extreme, by repeated exposure to noise at unsafe levels.

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For me, tinnitus began faintly and increased with more hearing loss, reaching a crescendo with one big acoustic trauma—a gunshot right next to me in 2009. I immediately began searching for any kind of treatment that would alleviate the loud ringing in my head, which was actually measured in a laboratory at being around a constant 70 decibels. That is roughly equivalent to the noise inside a fairly strong shower, and I soon discovered that people would use long showers to find a bit of relief by masking their tinnitus. (However, I take short showers!)

Armed with a background in biology and technology, I began to review all the research I could find. As it turns out, the typical tinnitus condition consists of several brain components: auditory (hearing it); attentional (your awareness of it); memory (persistence); and emotional (how it affects your mood). After many hours on the web, I spent thousands of dollars on things that didn't work, undergoing treatments in all areas of pharmacology, sound therapy, acupuncture, hyperbaric oxygen, and even transcranial magnetic stimulation.

None of these had any effect for me whatsoever. And despite some incredible recent advances in neuroscience to better understand all of the brain’s complexities, there is still no proven cure or even a viable treatment for tinnitus or to reverse hearing loss.

I eventually realized I would have to tackle my tinnitus with the only things out there that to me were credible for managing tinnitus. I eventually found an audiologist who would fit me with hearing aids that provided a built-in tinnitus masking sound. Without a doubt, this became the best purchase decision of my life...

Continue here to read the full version of "One Man's Military Perspective" in the Fall 2017 issue of Hearing Health. Colonel John T. Dillard, U.S. Army (Retired), resides in Carmel, California, with his wife of 30 years. A senior lecturer at the Naval Postgraduate School in Monterey, Dillard spent his army career serving in mechanized and parachute infantry assignments and managing programs to bring new technological capabilities to warfighters. He serves on a consumer review panel of tinnitus treatments for the Department of Defense (DoD)’s Congressionally Directed Medical Research Programs and also conducts acquisition policy research for the DoD.

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Protecting Your Hearing Means Protecting Your Mental Health

By Carol Stoll and Lauren McGrath

October is Protect Your Hearing Month—and, today, October 10, is World Mental Health Day, a time for mental health education, awareness, and advocacy. Hearing loss and tinnitus (ringing in the ears) can increase one’s risk of developing mental illnesses including depression, anxiety, schizophrenia, and dementia, and can trigger episodes of extreme anger and suicidal ideation. Protecting one’s hearing not only prevents or delays hearing loss, but also benefits mental wellness. Understanding the signs of mental illness and having access to mental health resources is critical—and can even be life-saving—to all individuals with hearing loss or tinnitus.

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According to an April 2014 study published in JAMA Otolaryngology Head & Neck Surgery, 11.4% of adults with self-reported hearing impairment have moderate to severe depression, significantly higher than the 5.9% prevalence for those with typical hearing. Individuals with hearing loss have reported feeling socially inept in group settings, entering conversations at inappropriate times, talking off-topic, or dominating conversations and coming across as rude simply because talking is easier than listening. When a person cannot hear properly, engaging in conversations is a daily struggle, and can lead to social isolation and depression. Other factors that increase the risk of depression include being female, low-income, a current smoker, binge drinking, having fair or poor health status, trouble seeing, and sleep disorder. However, even controlling for these factors, those with hearing impairment still had significantly higher rates of depression than those without hearing impairment. In people 65 and older, hearing impairment is among the most common chronic conditions associated with depression.

In addition to depression, hearing loss has been linked to schizophrenia. Several studies support the social defeat hypothesis, which proposes that social exclusion and loneliness can predispose people to schizophrenia by increasing sensitization of the dopamine system. In a December 2014 study published in JAMA Psychology, participants with hearing loss reported significantly more feelings of social defeat than healthy controls. Though their psychotic symptoms were similar to the control group, exposing them to a stimulant drug showed that those with hearing loss had significantly higher than normal dopamine sensitivity. Further studies are needed to draw definite conclusions of the causation, but this research is a first step in understanding the relationship between hearing impairment, social defeat, and psychosis.

In older adults, hearing loss is associated with cognitive decline and dementia, according to a February 2013 study published in JAMA Internal Medicine and several other studies conducted at Johns Hopkins University. The scientists concluded that reduced social engagement and a cognitive load focused on coping with hearing loss rather than higher level thinking can lead to poorer cognitive functioning and faster mental decline. Hearing aids could possibly be a simple fix to increase healthy brain function in the older adult population and reduce the risk of dementia.

Exposure to noise often results in tinnitus instead of or in addition to hearing loss, which can also contribute to a range of psychological disorders. Tinnitus affects about 1 in 5 people in the U.S., and causes permanent ringing in the ears. Though research for therapies is ongoing, there is currently no cure. Without therapy, constant ringing in the ears can be debilitating; it can affect job performance, cause insomnia, and provoke fear, anxiety, and anger. This can lead to depression, anxiety, suicidal ideation, and can exasperate post-traumatic stress disorder (PTSD).

Compromised hearing is an invisible disability, often unnoticed or ignored even by those affected. However, hearing loss and tinnitus are widespread and can have serious psychological repercussions. Hearing loss caused by noise exposure is completely preventable by taking simple measures like turning down the volume on your earbuds and using hearing protective devices in loud situations. Regular hearing screenings can also help detect hearing issues early on. Talk to your audiologist about best ways to treat or manage your hearing impairment. Find help for mental illnesses here.

Per the National Institute of Mental Health: "If you are in crisis, and need immediate support or intervention, call, or go the website of the National Suicide Prevention Lifeline (Voice: 1-800-273-8255 or TTY: 1-800-799-4889). Trained crisis workers are available to talk 24 hours a day, 7 days a week. Your confidential and toll-free call goes to the nearest crisis center in the Lifeline national network. These centers provide crisis counseling and mental health referrals. If the situation is potentially life-threatening, call 911 or go to a hospital emergency room.”

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

 
 
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An Animal Behavioral Model of Loudness Hyperacusis

By Kelly Radziwon, Ph.D., and Richard Salvi, Ph.D.

One of the defining features of hyperacusis is reduced sound level tolerance; individuals with “loudness hyperacusis” experience everyday sound volumes as uncomfortably loud and potentially painful. Given that loudness perception is a key behavioral correlate of hyperacusis, our lab at the University at Buffalo has developed a rat behavioral model of loudness estimation utilizing a reaction time paradigm. In this model, the rats were trained to remove their noses from a hole whenever a sound was heard. This task is similar to asking a human listener to raise his/her hand when a sound is played (the rats receive food rewards upon correctly detecting the sound).
 

FIGURE: Reaction time-Intensity functions for broadband noise bursts for 7 rats.    The rats are significantly faster following high-dose (300 mg/kg) salicylate administration (left panel; red squares) for moderate and high level sounds, indicative of temporary loudness hyperacusis. The rats showed no behavioral effect following low-dose (50 mg/kg) salicylate.

FIGURE: Reaction time-Intensity functions for broadband noise bursts for 7 rats.

The rats are significantly faster following high-dose (300 mg/kg) salicylate administration (left panel; red squares) for moderate and high level sounds, indicative of temporary loudness hyperacusis. The rats showed no behavioral effect following low-dose (50 mg/kg) salicylate.

By establishing this trained behavioral response, we measured reaction time, or how fast the animal responds to a variety of sounds of varying intensities. Previous studies have established that the more intense a sound is, the faster a listener will respond to it. As a result, we thought having hyperacusis would influence reaction time due to an enhanced sensitivity to sound.

In our recent paper published in Hearing Research, we tested the hypothesis that high-dose sodium salicylate, the active ingredient in aspirin, can induce hyperacusis-like changes in rats trained in our behavioral paradigm. High-dose aspirin has long been known to induce temporary hearing loss and acute tinnitus in both humans and animals, and it has served as an extremely useful model to investigate the neural and biological mechanisms underlying tinnitus and hearing loss. Therefore, if the rats’ responses to sound are faster than they typically were following salicylate administration, then we will have developed a relevant animal model of loudness hyperacusis.

Although prior hyperacusis research utilizing salicylate has demonstrated that high-dose sodium salicylate induced hyperacusis-like behavior, the effect of dosage and the stimulus frequency were not considered. We wanted to determine how the dosage of salicylate as well as the frequency of the tone bursts affected reaction time.

We found that salicylate caused a reduction in behavioral reaction time in a dose-dependent manner and across a range of stimulus frequencies, suggesting that both our behavioral paradigm and the salicylate model are useful tools in the broader study of hyperacusis. In addition, our behavioral results appear highly correlated with the physiological changes in the auditory system shown in earlier studies following both salicylate treatment and noise exposure, which points to a common neural mechanism in the generation of hyperacusis.

Although people with hyperacusis rarely attribute their hyperacusis to aspirin, the use of the salicylate model of hyperacusis in animals provides the necessary groundwork for future studies of noise-induced hyperacusis and loudness intolerance.


Kelly Radziwon, Ph.D., is a 2015 Emerging Research Grants recipient. Her grant was generously funded by Hyperacusis Research Ltd. Learn more about Radziwon and her work in “Meet the Researcher.”

We need your help in funding the exciting work of hearing and balance scientists. Donate today to Hearing Health Foundation and support groundbreaking research: hhf.org/donate.

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Some 1 Like You

By Makayla Allison

Our 6-year-old daughter, Lily, was recently diagnosed with Ehlers Danlos Hypermobility (EDS-HT). We received this diagnosis only after she acquired more than three dozen symptoms and diagnoses of uncertain significance, ranging from global joint pain and muscle weakness to tinnitus, and over the course of nearly five years.

It was a long and isolating time for our family as we tried to figure out what was going on. We so badly wanted to connect with someone who understood what our little one was going through, and when I asked Lily’s specialists if they could connect us with anyone, the answer was never yes due to privacy laws. Without a diagnosis it is nearly impossible to find groups of people in the same situation to talk to. And it can be even more frightening when the uniqueness of your symptoms isolates you even more.

The discovery of how Lily’s condition affected her hearing was both transparent and innocent. When Lily was 4 years old she asked me if the invisible bumblebees were going to sting her. She was so confused why she couldn’t see the bees that buzzed around her ears. It was shortly after she was referred to an ENT that we learned about tinnitus and that the sounds she hears come from inside her head.

Our daughter had a big desire to find a friend like her, but looking for someone else experiencing the same health challenges online, without posting them in great detail, was proving to be an impossible task. Her dreams inspired us to create Some 1 Like You (S1LY), an organization that connects people privately based on whatever health conditions they are experiencing, regardless of whether or not they’ve received a diagnosis.

According to the documentary film Undiagnosed: Medical Refugees, “The total number of undiagnosed patients is unknown but considered to be vast.... It takes an average of 7.6 years in the U.S. to uncover a rare disease diagnosis. Worldwide there are an estimated 350 million people living with a rare disease; add to [that number] patients still waiting for a diagnosis, patients who have been misdiagnosed, and adults and children who have diseases not yet named or recognized. Being ‘undiagnosed’ is not commonly considered to be an identity, but it should be. Helping people who are ill to feel that others are supporting and advocating for them, and know that they exist, can make all the difference in the world.”

Our mission for S1LY is to privately connect people across symptoms and diagnoses to empower the individuals facing these complex challenges. S1LY is unique because we can perform that search for people, while also keeping their health information private: To make these matches we take only their email address, as well as the health qualities, or groups of qualities they possess and are looking for in someone else.

Once a match is made, the email addresses of those members are shared with each other, and communication is then done only between members. It is our hope that this vast sharing of knowledge and resources among patients will make its way back to physicians and impact treatments as a whole across diseases.

S1LY has developed a Gifted Membership program to cover the lifetime membership fee to Some 1 Like You for constituents of qualifying organizations. 100 gifted memberships have been donated to the Hearing Health Foundation community. The first 100 people to submit their Connect Contact Forms to S1LY with the code “HHF100” will receive lifetime memberships to privately connect with Some 1 Like You members.

If you would like to explore gifted memberships for your patients or members at no cost, please email Makayla at gifted@some1likeyou.com. A portion of the proceeds of every S1LY membership goes to funding research on Ehlers Danlos Syndromes.

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