Research

Making Sense of Sound

Rush College of Health Sciences

In most auditory testing, the emphasis is on accuracy in speech recognition, since speech is our primary means of communication. But myriad sounds beyond language are key to our understanding of the world around us.

“A car honking, a baby crying, a fire alarm — recognizing these sounds can be important to our safety,” explained Valeriy Shafiro, Ph.D. “And there are also lots of nonlinguistic environmental sounds we enjoy listening to: the sound of the ocean, the wind in the trees when we walk in the woods.” Shafiro, an associate professor of communication disorders and principal investigator in the Rush Auditory Research Laboratory, conducts research in hearing and speech perception that focuses on finding new ways to diagnose auditory deficits and improve communication abilities in adults. These new diagnostic techniques have the potential to improve the quality of life of a variety of audiology patients — even well beyond the groups Shafiro is currently studying.

Addressing a rehab deficit 

Much of Shafiro’s lab’s past work, which has been funded by the National Institutes of Health (NIH), the American Speech-Language-Hearing Foundation (ASHFoundation) and the Hearing Health Foundation, formerly known as the Deafness Research Foundation, has assessed the ability of people with cochlear implants to recognize a variety of nonspeech sounds — a particularly useful means of auditory assessment in a large, urban medical center that treats many non-English speakers.

A recent study tested listeners’ ability to recognize those sounds with or without the contextual clues present in everyday life. For example, an ambiguous sound can be perceived as a burning fuse when preceded by the sound of a match being struck and followed by the sound of an explosion, but it may be perceived as bacon frying when surrounded by other kitchen sounds.

Credit: Rush University

Credit: Rush University

“Compared with people with normal hearing, people with cochlear implants show some pretty clear deficits in identifying environmental sounds as well as speech,” Shafiro said. “Research from several labs, including ours, shows the possibility for cochlear implant users to improve if they work on it. But there are few readily available opportunities for these patients to obtain rehabilitation, for reasons including travel difficulties, health care reimbursements and scope of practice.”

Shafiro is now evaluating the usefulness of Internet-based environmental sound and speech training for people who rely on cochlear implants in daily life. “A Randomized Controlled Trial to Evaluate the Benefits of an Internet-Based Auditory Training Program for Cochlear Implant Patients,” a two-year grant from the ASHFoundation, aims to help fill the rehabilitation deficit for adults who receive cochlear implants.

“With Internet access now widely available, patients can do the auditory exercises online, at their own pace and without having to travel,” Shafiro said. When completed, the study will give him and his colleagues a deeper understanding of the benefits and challenges of computerized auditory training.

Hearing-dementia link

Measuring listeners’ recognition of nonlinguistic sounds was also a component of a recent study from the Rush Auditory Research Laboratory in collaboration with the Rush Alzheimer’s Disease Center.

“Hearing, Speech and Episodic Memory in Older African-American and White Adults,” funded with a grant from the NIH, examined a topic of wide current interest: the relationship between aging, hearing loss and cognitive deficits. As Baby Boomers age, research like this has major implications for the health and well-being of older adults. “Some recent research has reported that people with a greater rate of age-related hearing loss also have a greater rate of cognitive decline,” Shafiro explained.

“Typical tests of working memory are based on retaining words or numbers, but we wanted to explore this further by measuring both nonspeech and speech perception.” 

Using tests previously designed by Stanley Sheft, senior researcher at the Rush Auditory Research Laboratory and principal investigator on the study, the team measured the ability of a cohort of community-dwelling older adults without known dementia to discriminate brief nonlinguistic sound patterns.

The addition of nonlinguistic sounds produced somewhat different results than those yielded by previous research. Although other studies have associated speech perception with cognitive performance, the Rush study did not find this correlation when measuring hearing thresholds or the ability to recognize speech in noise.

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However, “We found a relationship between working memory and the ability to discriminate brief auditory patterns,” said Shafiro, who hopes to revisit the study cohort in the future to see whether the tests may be predictive of the trajectory of cognitive decline.

This article was repurposed with permission from Rush University Medical Center, and originally appeared in the Rush College of Health Sciences magazine Impact. Valeriy Shafiro, Ph.D., is a 2008 Emerging Research Grants recipient.

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Moving Beyond Wnt and Notch Pathways for Hair Cell Regeneration

By Christopher Geissler, Ph.D.

There are several active human clinical trials evaluating the safety of inner ear hair cell regeneration therapies, but these therapies’ target mechanisms may be insufficient to stimulate hair cell growth in the adult mammalian cochlea. These approaches rely on the canonical Wnt and Notch signaling pathways and the Atoh1 molecule, which is necessary for hair cell regeneration and is regulated by these pathways. 

However, a report published in Molecular Therapy in May 2019 by Anshula Samarajeewa, Bonnie E. Jacques, Ph.D., and Alain Dabdoub, Ph.D., a member of Hearing Health Foundation (HHF)’s Hearing Restoration Project (HRP) consortium, notes that there has been very limited success thus far in regenerating hair cells in adult mammalian cochlea using these signaling pathways. This likely means, the authors write, that researchers will need combined approaches that also use epigenome-editing techniques to address changes to the genetic material and activity that occurs with age. 

Both the Wnt and Notch pathways play a role in determining how inner ear cells develop into specific types of cells and multiply, and they are also important in the development of the cochlea as a whole. Activating Wnt pathways and inhibiting Notch pathways can turn supporting cells into hair cells in fetuses and newborn mammals, making these key targets for hair cell regeneration. But both become much less effective as the body ages. Manipulating these pathways in adult animals has led to some success in regenerating hair cells, but these new hair cells tend not to develop fully, do not form necessary connections with auditory neurons, or even survive.  

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This lack of success is not because these pathways no longer exist in adults; researchers have found that they are still functional. This suggests that there are epigenetic changes that occur as a result of aging to make the adult cochlea less receptive to regeneration. Targeting epigenetic enzymes in addition to the Wnt and Notch signaling pathways may therefore prove more successful, but researchers still need to determine which part of the chromosome to target. This process would involve gene-editing techniques like CRISPR. This type of epigenome editing has slowed hearing loss in newborn mice, but it has yet to be tried in adult mice. If successful, this technique has the potential to treat hereditary and acquired forms of hearing loss.

HRP consortium member Alain Dabdoub, Ph.D., is a senior scientist, biological sciences at Sunnybrook Research Institute, University of Toronto. For more, see hhf.org/hrp.

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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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Stability in an Unstable World

By Timothy S. Balmer, Ph.D., and Laurence O Trussell, Ph.D.

Balmer & Trussell traced the direct and indirect pathways that carry vestibular information to the cerebellum for controlling balance and posture. Shown here is a primary afferent axon (green) expressing the light-gated ion channel, Channelrhodopsin. Postsynaptic cells, in this case a unipolar brush cell (magenta), were recorded from during stimulation of the input axons by light flashes. This technique was used to discover how direct and indirect vestibular pathways are processed in the cerebellum.

Balmer & Trussell traced the direct and indirect pathways that carry vestibular information to the cerebellum for controlling balance and posture. Shown here is a primary afferent axon (green) expressing the light-gated ion channel, Channelrhodopsin. Postsynaptic cells, in this case a unipolar brush cell (magenta), were recorded from during stimulation of the input axons by light flashes. This technique was used to discover how direct and indirect vestibular pathways are processed in the cerebellum.

Mice are helping scientists to understand how the world around us remains looking stable even as we move.

While out jogging, you have no trouble keeping your eyes fixed on objects in the distance even though your head and eyes are moving with every step. Humans owe this stability of the visual world partly to a region of the brain called the vestibular cerebellum. From its position underneath the rest of the brain, the vestibular cerebellum detects head motion and then triggers compensatory movements to stabilize the head, body and eyes.

The vestibular cerebellum receives sensory input from the body via direct and indirect routes. The direct input comes from five structures within the inner ear, each of which detects movement of the head in one particular direction. The indirect input travels to the cerebellum via the brainstem, which connects the brain with the spinal cord. The indirect input contains information on head movements in multiple directions combined with input from other senses such as vision.

Balmer & Trussell traced the direct and indirect pathways that carry vestibular information to the cerebellum for controlling balance and posture. Direct projections from the vestibular inner ear (green) and indirect projections from the brainstem (magenta) were shown to target different populations of neurons in the cerebellum.

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By studying the mouse brain, Balmer and Trussell have now mapped the direct and indirect circuits that carry sensory information to the vestibular cerebellum. Both types of input activate cells within the vestibular cerebellum called unipolar brush cells (UBCs). There are two types of UBCs: ON and OFF. Direct sensory input from the inner ear activates only ON UBCs. These cells respond to the arrival of sensory input by increasing their activity. Indirect input from the brainstem activates both ON UBCs and OFF UBCs. The latter respond to the input by decreasing their activity.

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The vestibular cerebellum thus processes direct and indirect inputs via segregated pathways containing different types of UBCs. The next step in understanding how the cerebellum maintains a stable visual world is to identify the circuitry beyond the UBCs. Understanding these circuits will ultimately provide insights into balance disorders, such as vertigo.

A 2017 Emerging Research Grants (ERG) scientist who received the Les Paul Foundation Award for Tinnitus Research, Timothy Balmer, Ph.D., is a postdoctoral fellow at the Oregon Hearing Research Center at Oregon Health & Science University (OHSU). Laurence Trussell, Ph.D., a 1991 ERG recipient, is a professor of otolaryngology–head and neck surgery at OHSU.

This research summary was repurposed with permission from eLife with permission.

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Improved TMC1 Gene Therapy Restores Hearing and Balance in Mice

By Christopher Geissler, Ph.D.

Half of all inner ear disorders, which have a negative impact on hearing and/or balance, are caused by genetic mutations. A study published in January 2019 in Nature Communications demonstrates the effectiveness of a gene therapy targeting one specific gene mutation, TMC1 (transmembrane channel-like 1). The research was conducted by Carl A. Nist-Lund in the Harvard Medical School lab of Gwenaëlle S. Géléoc, Ph.D., and Jeffrey R. Holt, Ph.D., with contributions from colleagues including 2017 Emerging Research Grants (ERG) recipient Jennifer Resnik, Ph.D., and her ERG co-principal investigator Daniel B. Polley, Ph.D., both also of Harvard Medical School.

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So far, 35 TMC1 mutations have been identified in humans, including several that are responsible for moderate to severe hearing loss, representing between 3 to 8 percent of cases of genetic hearing loss. This TMC1 gene therapy has had an encouraging level of success in mice and may prove capable of addressing similar genetic mutations in humans in the future.

Previous studies targeting this gene were only moderately successful in restoring function in inner hair cells, with little or no success in outer hair cells. Both types of hair cell are necessary for hearing.

The team decided to look at improving the mechanism that encodes TCM1 in affected mice, using a synthetic delivery vehicle they hoped would be more effective than the conventional one used in previous studies. In mice with this TCM1 mutation, hair cells begin to die when the mouse reaches 4 weeks of age. The treated mice in this study showed improved rates of survival in both inner and outer hair cells.

Most importantly, the improvement in hearing in the mice that received this intervention occurred primarily in the lower frequencies. Human speech is at the low to mid frequency range of the auditory spectrum, so if future human trials are able to replicate the success of this study, speech perception may improve.

The study additionally provided evidence of improved responses in the brain of the treated mice. This indicates that treatment of the cochlea by injection had knock-on effects in the auditory cortex, the part of the brain that plays an important role in hearing.

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Finally, the team recorded improved balance function in the mice that received the gene therapy. While only very young mice experienced better hearing, even older mice showed improvement in balance. The team writes that this improvement in balance function in mature mice may contribute to eventually developing a way to treat balance disorders in humans.

Jennifer Resnik, Ph.D., is a postdoctoral fellow in the Polley Lab, part of the Eaton Peabody Laboratories, Massachusetts Eye and Ear/Harvard Medical School. Her 2017 Emerging Research Grant was generously funded by Hyperacusis Research Ltd. Christopher Geissler, Ph.D., is HHF’s director of program and research support.

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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Single-Cell RNA Sequencing Reveals More Clues for Hair Cell Regeneration

By Mark E. Lush, Ph.D., and Daniel C. Diaz

Sensorineural hearing loss in mammals can often be attributed to damage or destruction of the delicate hair cells located within the inner ear. The microscopic hairlike projections on the surface of these cells are the key structure responsible for converting sound waves to electrical signals that travel to the brain through the auditory nerve. Unlike mammals, other vertebrates such as fish, birds, and reptiles routinely regenerate sensory hair cells during homeostasis and following injury. By studying the genetic program of hair cell regeneration in nonmammalian vertebrate organisms, researchers may discover therapeutic targets for treating hearing loss in humans.

The lateral line is a sensory system that allows aquatic vertebrates to orient themselves by detecting water motion. The lateral line organs (neuromasts), distributed on the head and along the body, contain approximately 60 cells, composed of central sensory hair cells surrounded by support cells and an outer ring of mantle cells. Using single-cell RNA sequencing, we combined some of the less well-defined clusters and identified major neuromast cell types, shown in this illustration, ranging from support cells to mature sensory hair cells. Credit: The lab of Tatiana Piotrowski, Ph.D., Stowers Institute for Medical Research, Kansas City

The lateral line is a sensory system that allows aquatic vertebrates to orient themselves by detecting water motion. The lateral line organs (neuromasts), distributed on the head and along the body, contain approximately 60 cells, composed of central sensory hair cells surrounded by support cells and an outer ring of mantle cells. Using single-cell RNA sequencing, we combined some of the less well-defined clusters and identified major neuromast cell types, shown in this illustration, ranging from support cells to mature sensory hair cells. Credit: The lab of Tatiana Piotrowski, Ph.D., Stowers Institute for Medical Research, Kansas City

One such organism, the zebrafish, has emerged as a powerful model for studying sensory hair cell regeneration. Like other fish, zebrafish contain a network of sensory hair cells throughout their body to detect changes in water movement. The hair cells are located in small organs in the skin called neuromasts, which also contains cell types that are remarkably similar to those found in the mammalian inner ear. To study the genetic program of hair cell regeneration in zebrafish, we sequenced the RNA of individual cells within neuromasts, allowing us to classify cell types based on their gene expression signature. This included cells transitioning from support cells to fully mature sensory hair cells, thereby identifying new genes that are expressed during hair cell development. In addition, we characterized the role of the growth factor fgf3, and found that it acts to inhibit hair cell progenitor proliferation. Our results were published in the journal eLife on Jan. 25, 2019. Future work will examine the function of these genes in sensory hair cell regeneration.

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Mark E. Lush, Ph.D., and Daniel C. Diaz both work in the lab of Tatjana Piotrowski, Ph.D., at Stowers Institute for Medical Research in Kansas City. Piotrowski is a member of the Hearing Restoration Project, which helped fund this study.

Empower the Hearing Restoration Project's life-changing research. If you are able, please make a contribution today.

 
 
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Hearing Restoration Project Scientific Director to Lead University’s Research Enterprise

By Tamara Hargens-Bradley, OHSU News

OHSU/Kristyna Wentz-Graff

OHSU/Kristyna Wentz-Graff

Peter Barr-Gillespie, Ph.D., will be Oregon Health & Science University’s (OHSU) first chief research officer and executive vice president, effective Jan. 1, 2019. Barr-Gillespie has served as interim senior vice president for research at OHSU since 2017.

In his new role, Barr-Gillespie will be principal adviser to OHSU President Danny Jacobs, M.D., FACS, on research strategy and research resource allocation. He will lead and manage OHSU’s research enterprise—comprising dozens of internationally and nationally acclaimed basic, translational, clinical, and public health research programs—and serve on the president’s executive leadership team.

“Dr. Barr-Gillespie has done a tremendous job leading the OHSU research mission on an interim basis. I’m delighted to appoint him to a new, permanent position that reflects his contributions and capabilities as well as the vital role of research at OHSU,” Jacobs says.

Barr-Gillespie also will collaborate with external academic, industrial and community research partners, and the various funding, regulatory and accrediting bodies. Moreover, he will represent OHSU in research collaborations with other universities in Oregon and the northwest region.

“I am excited to support Dr. Jacobs in developing OHSU’s 2025 strategic plan for research,” Barr-Gillespie says. “To be among the top-ranked research universities for NIH funding in the country and maintain our national reputation for cutting-edge research, we need to empower our researchers to do their best science by smartly investing in people, core resources, and space, and enhancing our graduate programs.”

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OHSU/Kristyna Wentz-Graff

Barr-Gillespie is an internationally recognized scholar, biomedical researcher and visionary academic leader who has been on faculty at OHSU since 1999. He currently holds faculty appointments in the departments of Otolaryngology/Head and Neck Surgery, Biochemistry and Molecular Biology, and Cell and Developmental Biology in OHSU’s School of Medicine and Oregon Hearing Research Center. He also is a senior scientist in the OHSU Vollum Institute.

An NIH-funded investigator, Barr-Gillespie’s research focus, his passion, is understanding the molecular mechanisms that enable our sense of hearing. Specifically, the Barr-Gillespie lab endeavors to determine how sensory cells in the inner ear called hair cells allow humans to perceive sound. Barr-Gillespie will maintain his active research program while serving as chief research officer.

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Barr-Gillespie is also the scientific director of the Hearing Restoration Project (HRP), an international consortium of 14 investigators funded by Hearing Health Foundation. The HRP’s goal is to develop a biological therapy for hearing loss arising from destruction of hair cells, which are not regenerated after damage from noise, ototoxic drugs, or aging.

Barr-Gillespie earned his bachelor’s degree in chemistry from Reed College in 1981, carrying out his senior undergraduate thesis at OHSU after a summer fellowship in OHSU’s biochemistry department. He received his doctorate in pharmacology at the University of Washington in 1988, and completed a postdoctoral fellowship in physiology, cell biology and neuroscience with Jim Hudspeth, M.D., Ph.D., at the University of California San Francisco and the University of Texas Southwestern Medical Center in 1993.

Following his fellowship, he accepted a faculty position in physiology at Johns Hopkins and remained there until accepting the position of scientist at the OHSU Vollum Institute and associate professor of otolaryngology/head and neck surgery in the OHSU School of Medicine in 1999. In 2014, Barr-Gillespie was appointed associate vice president for basic research at OHSU.

As a young investigator, Barr-Gillespie was named a Pew Scholar in Biomedical Sciences, a program that funds research “that shows outstanding promise in science relevant to the advancement of human health.” During his tenure at OHSU, he has been honored with the Faculty Excellence in Education Award and the John A. Resko Faculty Research Achievement and Mentoring Award.

Over his distinguished career, he has published more than 115 scholarly articles, chapters, and reviews, and has been an invited lecturer at dozens of research universities, academic conferences, and scientific events.

Barr-Gillespie and his wife, Ann Barr-Gillespie, D.P.T., Ph.D., live in Portland. She is the vice provost and executive dean of the College of Health Professions at the Pacific University Hillsboro campus. Their children are Aidan Gillespie, 17, and Katie Gillespie, 24, whom Peter and Ann share with their mother, Susan Gillespie. In their spare time, Peter and Ann enjoy cycling and hiking.

This is republished with permission from OHSU News.

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First Study to Examine Cognitive Development in Deaf Babies Finds Differences Begin in Infancy

By The Ohio State University Wexner Medical Center

Deaf children face unique communication challenges, but a new study shows that the effects of hearing impairment extend far beyond language skills to basic cognitive functions, and the differences in development begin surprisingly early in life. Researchers at The Ohio State University Wexner Medical Center are the first to study how deaf infants process visual stimuli compared to hearing infants and found they took significantly longer to become familiar with new objects.

 “This is somewhat counterintuitive because a lot of people assume that deaf children compensate for their lack of hearing by being better at processing visual things, but the findings of the study show the opposite,” said Claire Monroy, post doctorate otolaryngology fellow at The Ohio State University Wexner Medical Center and co-author of the study.

Macey Kinney plays with her 10-month-old son Zealand, who was born deaf. A new study shows that developmental differences in deaf babies extend beyond language and hearing, and begin surprisingly early in life. Credit: Ohio State University Wexner Medical Center

Macey Kinney plays with her 10-month-old son Zealand, who was born deaf. A new study shows that developmental differences in deaf babies extend beyond language and hearing, and begin surprisingly early in life. Credit: Ohio State University Wexner Medical Center

To test their visual processing skills, researchers showed infants different objects on a screen. When a baby has successfully encoded the object, they will lose interest and look away. This familiarization is what researchers call habituation. “Deaf infants took longer to habituate to the objects and looked away from them less than hearing infants,” said Derek Houston, associate professor of otolaryngology at Ohio State. “These results were surprising because you wouldn’t expect there to be such profound differences in a test that really has nothing to do with hearing.”

However, researchers say the results don’t necessarily mean that deaf children are learning at a slower pace. “Because they use vision to process the world around them, they may pay closer attention to visual objects,” said Houston. “They might actually be processing more about each object.”

Future research will examine why these differences in visual learning exist so that each child is taught in a way that works best for them and leads to healthy development. “Understanding the source of these differences can really help us tailor interventions specifically for these children,” said Monroy. “And the earlier that happens, the better.”

This article was republished with permission from the Ohio State University Wexner Medical Center. See the original press release here.

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