Hidden hearing loss is an issue for many people, even though they may not realize it. According to Dr. Fan-Gang Zeng, director of the Center for Hearing Research, "hidden hearing loss" is the term given to a form of hearing loss that cannot be measured on an audiogram. People with hidden hearing loss can have a normal audiogram but still claim difficulty with speech recognition and temporal processing.
For years, audiologists and scientists have been baffled by the mechanisms surrounding hidden hearing loss and why it takes place. Until 2014...
...it was thought by hearing health professionals that the cells in the inner ear are the most vulnerable part of our hearing anatomy. However, at the 167th meeting of the Acoustical Society of America, researchers from the Massachusetts Eye and Ear Infirmary revealed they had discovered the nerve fibers of the ear are more vulnerable to damage. Basically, if someone is exposed to enough noise pollution, the neurons in the inner ear can experience a lack of synapses, which can lead to the disappearance of the neuron entirely.
"Each missing synapse represents a cochlear nerve fiber that has been disconnected due to retraction of the terminal segment – it will never reconnect," said Charles Liberman, director of MEEI's Eaton Peabody Laboratory. "It no longer responds to sound, and, within a few months or years, the rest of the neuron will disappear."
Identifying hidden hearing loss
According to the National Institutes of Health, about 37.5 million American adults report some form of hearing difficulty. There are a few ways you can tell if you have hidden hearing loss. For instance, listening to the radio at top volume probably indicates an issue. In addition, some people have trouble distinguishing words from noise – leading to a need to lip-read. If you find yourself in situations where you need to lip-read or ask conversation partners to repeat what they've said, chances are you have some form of sensorineural or conductive hearing loss.
Another condition that has been connected with hidden hearing loss is tinnitus, or ringing in the ears. The Tinnitus Research Initiative reports around 10 percent of people with tinnitus have a normal audiogram, meaning their hearing loss doesn't register. It's important to get your hearing checked if you experience tinnitus.
Prevention is key
We all need to take better care of our hearing. Hearing loss prevention is an important part of daily health. Loud music, train and car sounds, and aging are all culprits of sensorineural damage to your ears. Limiting the occurrence of noises above 80 decibels can go a long way toward preserving your hearing as long as possible.
If you are concerned about hearing loss – hidden or otherwise – for yourself or someone important to you, contact an audiologist or a hearing health care professional at your local AccuQuest Hearing Center to schedule an appointment.
If you want to learn more about how your hearing works, hearing loss and hearing aids, how hearing aids work or why it is a good idea to see an audiologist or hearing health care professional, click here to view and download your own copy of AccuQuest's Journey to Better Hearing.