Cranking the volume up can bring hearing down

Earbuds such as these may contribute to hearing loss in people who listen at exceptionally high volumes or for extended periods of time.

Listeners should avoid blasting the sound so high that they can't hear surrounding conversations or so that others can hear the music from the listener's headphones or earbuds, says Paul R. Kileny, director of audiology in the Department of Otolaryngology.

"These portable devices are not inherently harmful to hearing because of the way they are coupled to the ear, but there are certainly safe levels at which one can listen to them," Kileny says. "My recommendation is to listen at such a level that one can still hear conversation and other people in their environment do not accuse them of shouting when they attempt to converse."

The effects of listening to music that is too loud can be permanent, Kileny says. He notes that he and other doctors in his field are seeing more and more young people with noise-induced hearing loss.

"As you pass some of these young people, you can actually hear the music radiating from under those little headphones," says Kileny, who also is a professor in the Department of Pediatrics and Communicable Diseases and a member of the Geriatrics Center. "That is a sure sign that the individual listening to that music is listening at a level that is too loud, and, therefore, in the long run is risky to the status of their hearing."

While it is ultimately up to listeners to control the sound emanating from their headphones, Kileny and other audiologists recommend that sound controls built into the devices would be extremely helpful in encouraging people to keep the volume at reasonable levels. In turn, such controls could help reduce the number of people with early sound-induced hearing loss, he says.

"With these personal audio players, there are no built-in electronic safety cut-offs or safety devices that preclude listening at a dangerous level or that at least inform the wearer that he or she has reached a level which might be risky to hearing," Kileny says. "It's very simple technology that could be built into these devices."

The controls could be as simple and unobtrusive as a warning light that turns on when the sound surpasses a certain decibel level, he says. That could be especially useful for people who tend to listen to music through headphones or earbuds in noisy places, such as buses or subways, he says.

In addition to hearing loss, listening to music too loudly can lead to tinnitus, a ringing, whistling or clicking sound in the ears. The American Tinnitus Association estimates that up to 90 percent of all tinnitus patients have some level of noise-induced hearing loss.

"Any kind of sound—whether it's pleasant, such as music, or unpleasant, such as noise—can cause hearing loss at excessive levels," Kileny says. "The way this happens is that the excessive sound level or noise level will act upon the sensitive receptor cells inside the inner ear—the so-called hair cells. Due to excessive exercise that those hair cells undergo under these conditions, damage will occur.

"That damage might be temporary, after a brief exposure, and then if you rest your ear for a certain amount of time, much of the hearing loss caused by this damage might resolve itself," he says. "But then, as you add more and more episodes of this kind of exposure, ultimately the damage is going to be permanent."

Years ago, U-M conducted research on hearing loss related to the then-popular Walkman and similar personal stereos. They found hearing loss in young people, but not at the levels they are seeing with modern devices.