ANN ARBOR, Mich. – It can happen in a noisy lunchroom or a crowded restaurant. You find you just can't seem to hear what people are saying.
Haley Otman works in the communications department at Michigan Medicine, but she's noticed an issue in her own communicating.
"When I'm in a meeting or talking on the phone or something, I never have any problem hearing people, but I do notice that I do have to ask people to repeat themselves when I'm in a restaurant or bar," said Otman. "Once I learned about hidden hearing loss, I thought it made a lot of sense."
Otman is far from alone.
Dr. Paul Kilney, the director of audiology at the University of Michigan, has seen many patients that complain of hearing issues, but when they undergo a traditional hearing test.
"It comes out pretty normal, or close to normal, and you look at it and say, 'I don't know what you are talking about 'cause everything tests out perfectly fine,'" said Kilney.
Kilney now believes many of these patients are suffering from hidden hearing loss. He's teamed up with researcher Dr. Gabriel Corfas, director of the Kresge Hearing Research Institute.
"There's a lot more noise exposure these days. We live in a very noisy society, noisy environment," said Corfas.
Hidden hearing loss was first described by researchers in the United Kingdom just a few years ago.
Corfas said loud noise can damage the connections between hair cells in our ears -- cells that are essential for hearing.
"It was discovered that these noise exposures cause a permanent hidden hearing loss that eventually leads us, in years, to have very significant defects in hearing in noisy environments," said Corfas.
As a result, you may hear just fine in quiet settings, but struggle in noisy situations.
Now by studying the problem in mice, researchers at the University of Michigan have found a second cause for hidden hearing loss -- the loss of myelin -- which insulates nerves critical for hearing.
"Right now, we are going to be working together with our clinicians and audiologists to see whether that happens and to try to understand how profound it is and think how we can cure it," said Corfas.
Kilney says a test already used by audiologists for other purposes may help determine who is suffering from hidden hearing loss. Instead of measuring how well someone hears, it measures how well the hearing nerve itself functions.
"This is as close as we can get to the hearing nerve, using a non-invasive procedure," said Kilney.
The next step is to compare normal test results to test results in people thought to be suffering from hidden hearing loss.
The ultimate goals are to find better ways to diagnose hidden hearing loss and guide research to find drugs to treat it.
These experts hope just being able to show patients that it's occurring might help prevent further damage.
"Once there is hidden hearing loss, after a while then, the hidden hearing loss becomes not so hidden hearing loss," said Kilney. "We can probably prevent this if we change your behavior a little bit."
Currently, there's no treatment for hidden hearing loss, so the focus is on prevention. That means protecting your hearing from loud noises, including loud music.
"That exposure can really be damaging our ability to hear for the rest of our lives," said Corfas. "Just keep the volume down. If somebody else can hear what you are playing in your earbuds, then that is a problem."
It's advice Otman already follows, hoping to preserve her hearing for many decades to come.
"I don't use ear buds that often," said Otman. "I do love listening to music, but I try to watch the volume, especially in the car."
To learn more about the research, click here.