USF Researchers Receive $9 Million Grant to develop strategies to treat age-related hearing loss
Scientists at USF’s Global Center for Hearing and Speech Research (GCHSR) and the Auditory and Speech Sciences Laboratory have received a five-year, $9 million grant from the National Institutes of Health (NIH) to study two unique ways to treat age-related hearing loss (ARHL). The vast majority of people over age 60 are affected by this progressive decline in auditory sensitivity and difficulty understanding speech in noise. While ARHL is one of the top three chronic medical conditions of the elderly, there currently are no approved medical treatments for preventing or reversing permanent hearing loss (ARHL or other types). Despite decades of research and discovery, overcoming the barriers of ARHL through prevention and treatment continues to represent a major scientific and clinical challenge.
The current research project focuses on changing the way the ear and the brain process sound. One arm of the study focuses on the naturally occurring hormone, aldosterone. Aldosterone regulates various functions of the body that are necessary for normal physiology, including the physiology of the auditory system. Using behavioral and neurophysiological methods, researchers at the GCHSR have been developing an animal model to determine if boosting aldosterone has a positive effect on hearing loss. They will do this by focusing on the neural mechanisms associated with hearing and how those neural codes are altered due to aging, both in mice and in humans. Parallel work in humans will include monitoring aldosterone levels in older adults over a four-year period to determine how changes in aldosterone over time and across people relates to auditory function and perception. This work will provide insights key to determining if hormone intervention could be a viable solution to ARHL.
A second arm of the study involves understanding the principles of brain plasticity and exploring the possibility that brain plasticity could be controlled in a clinical environment to overcome the key deficits associated with ARHL. ARHL is associated with changes to our perception of the loudness of sounds, and this makes it challenging for hearing aids to make soft sounds audible without making loud sounds too loud. Likewise, ARHL leads reduction in the fine timing needed to encode the details that give sounds clarity and a rich quality. This timing deficit can also make it difficult to accurately hear certain sounds and separate them from background noise. An initial step will be to determine whether the type and degree of central auditory plasticity changes with age. The next step is to alter the sound environment in an effort to induce neural plasticity in the auditory system. In this step, the focus will be to change the way the brain processes sound to try to overcome the most pronounced consequences that aging has on hearing. To do so, participants in the research will be presented with an enriched acoustic environment to induce and possibly steer neural plasticity.
The team of scientists collaborating on this grant combines expertise in perception, hearing enhancement devices, neurophysiology, molecular biology, and engineering. The research team will begin recruiting approximately 150 older individuals this year to participate in various studies. Please contact the USF Auditory and Speech Sciences Laboratory if you are interested in participating.