Aging & Health A to Z

Hearing Loss

Basic Facts & Information

What is Hearing Loss?

About a third of adults older than 65—and half of those older than 85—have some hearing problem. It is the fourth most common chronic disease among older adults.
Hearing loss is more than an inconvenience; it can lead to depression, withdrawal, anger, loss of self esteem, and overall unhappiness with life. There’s even some evidence it can affect your memory and other cognitive processes, as well your mobility. Because it can make communicating with your healthcare professional difficult, hearing loss can even jeopardize your overall health.
Age related hearing loss (ARHL) happens gradually over time, so that although those around you may notice problems, you may think you’re fine. Interestingly, once people are diagnosed and begin using hearing aids or other forms of hearing assistance technologies, do people realize how much hearing they have lost.
The bottom line is that treating hearing loss can significantly improve the quality of your life and interactions with others, including relieving the depression often associated with hearing loss.

Sound and the Ear

We define sound in two ways:

Frequency (pitch), which is measured in cycles per second. Normal speech falls in a frequency range of 250 to 8,000 cycles per second with most of the range important for speech understanding lying in the higher frequencies (for example, 1500 to 4000 Hz).
Intensity (loudness), which is measured in decibels. The lowest intensity at which a sound must be generated to be heard is called the threshold for hearing. The higher your individual threshold, the louder the sound has to be made to be heard and the worse your hearing.

Normal hearing depends on three components: your ear, the nerves leading from the ear to the brain, and the brain. The ear modifies the sounds coming from the outside and the brain processes and helps us understand and interpret sound.
Hearing starts with a sound wave, or vibration. The sound wave travels through the outer part of your ear (ear canal) and travels to the eardrum which is a thin membrane that separates the outer parts of the ear from the inner parts. When the ear drum vibrates, three bones (auditory ossicles) send the vibration to the cochlea (tiny spiral cavity with sensory cells), and the signals are carried by nerve fibers to the brain where speech understanding takes place.

Hearing Loss Defined

Hearing loss is formally defined as the loss of the ability to hear pure tones across the range of audio frequencies required to understand speech. The hearing loss contributes in large part to difficulty understanding what others say especially in noisy conditions. ARHL usually occurs in both ears.
There are three main types of hearing loss which include: conductive, sensorineural, and mixed. ARHL is sensorineural in nature.

Updated: March 2012
Posted: March 2012