Hearing Loss V Visual Loss - Time to Listen
It is common for both hearing and vision (properly referred to as "visual") loss to occur as we age. Normal, healthy people will lose hearing because the hair cells in the ear, which interpret sound vibrations, become damaged or die over time, and they will experience visual loss as the flexibility of the crystalline lens in the eye is gradually reduced. Visual loss caused by aging is defined as an otherwise perfectly shaped eye (in other words not an eye with a misshapen cornea as found in near or farsighted individuals) most often occurs in people over 40. However, hearing loss from aging can start as early as age eight.
On average, humans hear a range of sounds between 20 Hz (Hertz: cycle per second) to 20,000 Hz. Hearing high frequency sounds, those above 2,000 Hz (abbreviated 2 kHz), begin to fade as early as age eight. By the time a person reaches age 25, he or she generally cannot hear above 15 kHz. Speech is considered a high frequency sound, generally landing between 2 kHz to 8 kHz. As higher frequency hearing is lost, "s" or "th" sounds often become difficult to differentiate, and women's voices (registering higher) become harder to understand. Ultimately, speech will sound muffled. If a person is aging normally, 15 kHz is still extremely high, and does not adversely affect the ability to hear speech. However, humans are easily prone to speeding up the loss of their own high frequency hearing.
Loud noise is the greatest contributor to high frequency hearing loss. Prolonged exposure to sound above 85 decibels will damage the hair cells. Because these cells do not regenerate, hearing loss will occur. While occupational noise from industrial machines found in construction, factories, the military or farming has been the common cause of this type of hearing loss in the past, today, loud music pumped through headphones plays an equal risk. An iPod, for example, reaches 85 decibels at 60% of its potential volume. A Florida study discovered up to 24% of iPod users chronically listen to levels exceeding this safe decibel range. In general, the more ambient noise (say on a bus or at a coffee shop), the louder the listener is likely to turn up the volume, and the more likely they are to be causing damage to their hearing.
Traditionally, glasses are a socially acceptable aid for those with visual loss, while hearing aids still hold on to a negative stigma. In addition, more people are likely to get periodic eye check-ups than hearing exams. Since hearing loss is an inevitable part of aging, (and one we seem to be very good at accelerating) it is equally important to get regular hearing tests. And with advances in technology, hearing aids are virtually invisible, eliminating the embarrassment which might have come from the old fashioned devices. Hearing loss is part of aging, but it doesn't have to be part of your suffering.
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