March 17, 2011 -- Many college students think they can hear just fine, but new research suggests that up to one-fourth of them may actually have evidence of early hearing loss. The new finding appears in the International Journal of Audiology.
Researchers made this discovery while recruiting college students with normal hearing for a study that looked at the whether the use of personal music players can cause temporary hearing loss. Several of the students who reported normal hearing during telephone interviews showed signs of hearing loss when tested.
“We were very surprised, especially because we used extremely liberal criteria for normal hearing,” says study author Colleen Le Prell, PhD, an associate professor in the department of speech, language, and hearing sciences at the University of Florida in Gainesville.
One-quarter of 56 students at the University of Florida in Gainesville who reported normal hearing during initial phone interviews actually measured 15 decibels or more of hearing loss at one or more test frequencies. This degree of hearing loss is enough to disrupt learning, Le Prell says.
“This suggests that we need to be careful about classroom acoustics and that students with this degree of hearing loss should sit up close; and we should take steps to reduce background noise in classrooms,” she says.
Students completed a health survey and a questionnaire about their exposure to loud noise and underwent hearing tests in a sound booth at all of the sound frequencies used in a traditional full-hearing test.
Of the participants who demonstrated hearing loss, 7% had 25 decibels or more of hearing loss, which is “mild hearing loss.” Hearing loss occurred in both the range of frequencies identified as “speech frequencies” because they aid in speech discrimination, as well as the higher frequencies.
Do Personal Music Players Contribute to Hearing Loss?
The highest levels of “high frequency” hearing loss occurred among male students who reported using personal music players such as iPods and MP3 players, the study showed. However, more research is needed with a larger group of participants to determine the role of personal music players in hearing loss, Le Prell says.
Exactly what role the use of such personal music devices play in hearing loss is not fully understood.
“There is potentially an issue and we need some more data to figure out how real and how pervasive the problem is,” Le Prell says.
Her advice for people who use these devices? “Turn it down,” she says. “If you can't hear someone speaking to you while listening to your music player device, it’s too loud,” she says. Also, consider investing in noise-reducing headphones.
Capture Students at Risk for Hearing Loss
Le Prell suggests that college students get hearing evaluation tests annually or at least before they begin college and again at graduation.
“The goal would be to identify people with early signs of hearing loss and counsel them about ways to protect their ears,” she says.
“College students may feel invincible, but all of this stuff catches up to you, and if you lose nerve fibers in the ears, you don’t get then back, and their loss is associated with life-altering hearing ability and tinnitus,” or ringing in the ears, says Rick A. Friedman, MD, PhD a head and neck surgeon at House Ear Clinic and scientist at House Ear institute in Los Angeles.
Some people may be more sensitive to noise exposure than others, he says.
“The literature on personal music devices and MP3 is not conclusive, but it is clear that if you are exposed to noises above certain decibels, you can get shifts in hearing,” Friedman says. “We are starting to see the impact of these personal music players on hearing. You should not bypass the sound governors on iPads and iPods and iPhones. Don’t listen too loudly, and once these sensory cells are lost, they are lost for good.”