The popularity of portable digital music players has risen so much over the past few years that it's almost impossible not to spot an Apple iPod Mini or a Creative Zen on campus. However, recent studies show that music lovers may want to think twice before turning up the volume on their mp3 players. Listening to loud music with headphones that attach directly to the ears could cause noise-induced hearing loss, according to researchers. Those impaired sometimes lose the ability to discern high frequencies and have trouble following conversations in areas with a lot of background noise.
The tendency of teenagers to listen to music louder and longer than older adults puts them at a greater risk. Nevertheless, hearing specialists say even people in their 30s and 40s have complained about encountering internal ringing or buzzing noises in their ears from listening to portable audio players over a period of time. Many of those affected were among the first to use the portable Walkman that came into the market a few decades ago. The results of the study raise important questions about the effects of long-term portable audio use.
Hearing damage is not limited to headphone devices from audio players and cell phones. Individuals who frequently attend loud concerts and clubs, and who drive vehicles such as trucks and motorcycles are also at risk of acquiring hearing loss in the future. Repeated exposure to any combination of these over time could result in long-term hearing damage.
Researchers predict eardrum damage incidences will grow with the invention of new headphones. As the trend for smaller audio players continues, bulky and cumbersome headphones are quickly becoming obsolete. New styles such as iPod "ear buds" fit firmly into the ear without the need for head support. Manufactured to accompany compact digital music players, ear buds send concentrated sound directly into the ear that could potentially damage the eardrums.
Deanna Meinke, an audiologist at the University of Northern Colorado, points out that digital music players now come with built-in batteries that last longer than previous audio players. The increase in listening time coupled with shorter rests in between tracks leads to a higher risk of hearing loss.
Visual impairment can generally be corrected by eyeglasses because the sensory part of the visual system is still intact. "Hearing loss, however, generally results from damage to the sensory receptors. Once those receptors are lost, they cannot be replaced," said Dr. David K. Ryugo, a professor in Hopkins' Department of Neuroscience.
Perhaps the most unsettling fact is that people do not know whether they are at risk until it's too late. According to Dr. Colin Driscoll, an otologist at Minnesota's Mayo Clinic, it can take years and many repeated exposures for someone to realize they are at risk.
Before the marketing of personal stereo systems, hearing loss used to be a disability attributed to the aging or those working around noisy equipment. Now, "blasting sounds into the ear by headphones represents one of the main sources of hearing loss around the world," says Ryugo.
Ironically, people who listen to music to block out noise pollution at locations like public transportation stations and street corners are also at risk. The ineffectiveness of "ear buds" in blocking ambient noise prompts listeners to raise the volume levels on their music players. Dr. John K. Niparko, a professor at the Department of Otoaryngology -- Head and Neck Surgery, advises the use of "an occlusive, muffled headset [that] is much more effective in blocking surrounding sound. The leakage of high tones from the headset to the ear canal is reduced, providing greater fidelity."
This is not to say listening to portable music players leads to hearing loss. Those who listen to music at high volumes should be cautious about future risks.
