Staff Standpoint | October 2022 Hearing Review

November Edition – Interview with Mass Eye and Ear Otolaryngologist Michael S. Cohen, MD, Director, Multidisciplinary Pediatric Hearing Loss Clinic, & Director of the Pediatric Otolaryngology Fellowship at Massachusetts Eye and Ear (pictured above).

A team of Mass Eye and Ear researchers in the Eaton-Peabody Laboratories have been awarded a five-year, $12.5 million P50 Clinical Research Center Grant from the National Institute on Deafness and Other Communication Disorders (NIDCD) of the National Institutes of Health (NIH) to continue their research on cochlear synaptopathy, or hidden hearing loss, a type of hearing damage that was reportedly first discovered, according to an announcement from Mass Eye & Ear.

Kathryn Sutherland

Sharon G. Kujawa, PhD; Charles Liberman, PhD; Stéphane F. Maison, AuD, PhD, CCC-A; and Daniel B. Polley, PhD, are the collaborating Mass Eye and Ear principal investigators on the project. 

Funding from the grant extends support for four projects that aim to clarify the prevalence, nature, and functional consequences of hidden hearing loss in humans. 

Hidden Hearing Loss

The audiogram is considered the “gold standard” by clinicians for hearing tests. The test reflects the health of sensory cells in the inner ear, called hair cells, which convert sound into electrical signals. While the health of these cells can determine a person’s hearing threshold or how loud a sound needs to be in order for a person to hear it, the thresholds do not reveal how clearly sounds are listened to. 

In 2009, Drs Kujawa and Liberman discovered that noise exposure destroys the synapses connecting hair cells to the auditory nerve well before the noise damaged hair cells, which meant hearing damage could exist before it was revealed by the audiogram.

This prompted the researchers to evaluate widespread neural degeneration in patients with hearing difficulties and normal audiogram measurements.

New Grant to Build on Earlier Grant Projects

In 2017, the NIH awarded Drs Kujawa, Liberman, Maison, and Polley a P50 grant to research this new type of hearing damage from multiple angles.

Their research also revealed several clues about this hearing damage. Growing evidence has suggested that perceptual disorders, some as mild as difficulty hearing in a noisy environment or as potentially debilitating as tinnitus and hyperacusis, could share a common tie to neural degeneration. Additionally, studies found that sound deprivation can lead to neural decline, not just aging, loud noises, or ototoxic drugs, that can lead to neural degeneration.

The new P50 grant will bring researchers closer to devising sensitive diagnostic tools, thereby enabling future therapeutics to prevent, limit, or reverse cochlear neural degeneration.

Featuring topics covered at AAO-HNSF 2022.

—Kathryn Sutherland, Director of Business Intelligence


  1. Jaslow R. Mass Eye and Ear researchers awarded a $12.5 Million NIH grant to continue hidden hearing loss research. Mass Eye and Ear website. Published July 25, 2022. .