Hidden Hearing Loss Linked to Tinnitus, Harvard Study Finds

Written by Camilla Jessen

May.10 - 2024 9:40 AM CET

Photo: Shutterstock.com
Photo: Shutterstock.com
Researchers at Harvard University have discovered that tinnitus may be a sign of hidden hearing loss.

Trending Now

Tinnitus, a condition characterized by a persistent ringing or whining sound in the ears, affects between 10 to 25 percent of adults globally, according to the World Health Organization (WHO).

Despite its prevalence, no effective treatment has been identified — until, perhaps, now.

Researchers from Harvard University, in collaboration with Massachusetts Eye and Ear, have made significant strides in understanding the underlying causes of tinnitus. They believe it is linked to a form of hearing loss not detectable by standard hearing tests.

Brain Activity Increases in Response to Nerve Damage

The study revealed that individuals with chronic tinnitus tend to experience a loss of auditory nerve fibers and exhibit increased brain activity. This pattern was not observed in individuals without tinnitus.

The research supports the theory that the brain compensates for hearing loss by increasing activity, which inadvertently generates the internal sounds associated with tinnitus.

The findings were published in a recent press release by the university, shedding new light on the mechanisms behind this often-debilitating condition.

The damage to the auditory nerve, which transmits sound signals from the ear to the brain, is central to the development of tinnitus.

Conventional hearing tests, which typically assess the ability to hear external sounds, fail to detect this nerve damage. This has led researchers to suggest that tinnitus might actually be a symptom of this "hidden" hearing loss.

Hope for Treatment

For those who recognize their hearing loss, interventions such as hearing aids can alleviate tinnitus.

But when tinnitus exists without recognized hearing loss, patients often do not receive the necessary support, leaving them to struggle with the condition unaided.

The study, however, offers a glimmer of hope.

Researchers note that while some nerve fibers are destroyed, others remain intact, and animal studies have indicated that it is possible to regenerate these fibers.

"If one day we can regenerate fibers in humans, it may be able to return lost information to the brain and thereby reduce brain hyperactivity and the perception of tinnitus," explained Stéphane Maison, a researcher specializing in tinnitus and a professor at Harvard Medical School’s Department of Otolaryngology–Head and Neck Surgery.

This breakthrough could pave the way for new treatments that not only help manage tinnitus but potentially reverse the underlying causes associated with nerve damage.

Most Read