$5.7 million NIH grant to fund hearing studies
Investigators to expand multidisciplinary research into causes of acquired hearing loss

By LOIS BAKER
News Services Editor

The Center for Hearing and Deafness, one of the world's leading hearing-research laboratories, has received a $5.7 million program project grant from the National Institutes of Health to expand studies geared to understanding and treating acquired hearing loss.

The five-year grant funds four projects on the function of the peripheral and central auditory system that aim to determine how and why noise and certain therapeutic drugs cause loss of hearing.

Acquired hearing loss, as distinguished from hereditary hearing loss, affects approximately 28 million people in the United States alone.

The project is grounded in a dozen years of research conducted at UB by a team of internationally recognized scientists in the Center for Hearing and Deafness, a multidisciplinary effort involving 30 scientists spanning eight departments and three schools within UB.

A program project grant, sometimes characterized as "big science," provides researchers with the funding to tackle problems, such as acquired hearing loss, from several directions at once.

Richard J. Salvi, professor of communicative disorders and sciences and otolaryngology, is chief investigator on the grant.

"This grant is wonderful news for the university," said President William R. Greiner. "It will enable Professor Salvi and his team to expand their pathbreaking research into the causes of acquired hearing loss.

"Their outstanding work is a stellar example of the interdisciplinary research that we foster at UB," Greiner added. "Their studies promise not only to advance scientific knowledge about acquired hearing loss, but to benefit millions of people who suffer from this affliction.

"We are proud that our center received this prestigious NIH grant, and look forward to its continued success as a worldwide leader in its field."

Provost David J. Triggle noted that "program project grants provide funding to a group of investigators at an institution with the opportunity to research several related directions simultaneously. The process encourages multidisciplinary efforts, often a very productive pathway in cutting-edge areas of science.

"Hearing research," Triggle added, "is such a process demanding interdisciplinary research and is of increasing significance, given the multiple impact on human hearing loss ranging from age, environmental noise and ototoxic agents."

The Center for Hearing and Deafness was established in 1987 by Donald Henderson, professor of communicative disorders and sciences and otolaryngology, and Salvi, both of whom came to UB that year from the University of Texas in Dallas. They were joined in the mid-'90s by researchers Robert F. Burkard, associate professor of communicative disorders and sciences and otolaryngology, and Sandra L. McFadden, research assistant professor of communicative disorders and sciences and psychology.

The team in recent years has produced a body of groundbreaking basic research into the causes and mechanisms of acquired hearing loss.

Members have active collaborations with the University of Rochester, Albert Einstein College of Medicine, SUNY Health Sciences Center in Brooklyn, Southern Illinois University, the Robert Taft Research Labs at the National Institute for Occupational Safety and Health, and the U.S. Navy. In 1994, the Center for Hearing and Deafness was designated a Center of Excellence by UB.

In recent years, the center's research has focused on four overlapping themes that form the basis for the current program project grant.

The projects target molecular and cellular mechanisms of hearing loss, effects of ototoxic agents and noise on cochlear function, functional alterations of the central auditory brain regions after partial or temporary hearing loss and the role of the ears' inner hair cells in the brain's processing of auditory stimuli.

"To understand why a patient experiences difficulty in processing complex sounds, we need first to understand how the auditory system processes acoustic information along the entire auditory pathway," said Salvi.

"Damage that originates at the periphery, or inner ear, can cascade through the system, disturbing activity throughout the entire auditory pathway, even spilling over to other sensory, motor, cognitive and emotion centers. This functional reorganization, or plasticity, is poorly understood because of a lack of an integrative research approach to acquired hearing loss. Our project provides such an approach."

Each of the four areas of study funded by the grant addresses a major problem, while relating and interacting with the others. As in their past studies, the researchers will use chinchillas as an animal model because their hearing range is similar to a human's.

The projects are:

The Role of the Ears' Inner Hair Cells in Hearing and Hearing Disorders

Headed by Salvi, it will focus on the function and behavior of the ears' inner hair cells at the level of single auditory nerve fibers.

Responses of the Central Auditory System to Peripheral Damage

This project, headed by Burkard, will try to determine how the central auditory system responds when some or all of its auditory nerve input is either permanently or temporarily eliminated.

The Role of Antioxidants in Noise-Induced Hearing Loss

In this project, Henderson will continue his exploration of the relationship between concentrations of protective antioxidant enzymes and the degree of noise- or drug-induced hearing loss. The aim of the study will be finding ways to protect the inner ear from damage.

Efferent Influences on Susceptibility to Cochlear Damage

This project, headed by McFadden, also will explore ways to protect the ear from noise- and drug-induced damage. It will seek to understand how specialized nerve fibers from the brain influence the degree of cochlear damage from noise and ototoxic drugs.

In addition to their basic scientific merit, the four projects in the program have implications for preventing and treating hearing loss in humans. Salvi said the first two projects were motivated by a growing awareness that the ears' inner hair cell loss may underlie many of the perceptual difficulties experienced by people with sensorineural hearing loss and by concern over the lack of clinical methods for assessing loss of the ears' inner hair cells.

The third and fourth projects were motivated by the sense that susceptibility to hearing loss from ototoxic drugs and noise may vary tremendously among individuals, that identifying factors that contribute to susceptibility may be crucial to preventing or treating acquired hearing loss and that a possibility exists that pharmacologic intervention may reduce the hearing loss produced by exposure to noise or ototoxic drugs.

Additional UB researchers involved in the project are Dalian Ding, a neuroanatomist and research support specialist, and Xiang Yang Zheng, an auditory physiologist and research assistant professor, both in the Department of Communicative Disorders and Sciences. The grant also provides financial support and research training for graduate and undergraduate students.