Although

most people with hearing loss have a binaural (both ears)

loss, there is also the less common unilateral, or one

sided, hearing loss.

The most

clear example of this pattern is the person with perfect

hearing in one ear and a complete loss of hearing in the

other ear.

Typical

causes of the unilateral loss are trauma (blow to the

head), ear infection, viral infection, a blockage in the

blood flow to the ear, and inherited hearing loss and

even earwax blocking the ear canal.

If a child

is born with unilateral hearing loss, the loss is often

not detected until 5 or 6 years of age because the child

will appear to hear normally and speech and language

development should not be affected.

Another

common case is the person with significant hearing loss

in both ears who uses only one hearing aid. This person

will experience the same difficulties as the person with

the unilateral loss, even if hearing in the aided ear is

excellent. Some of these difficulties are one-sided

hearing, understanding speech in noise, determining the

sound source and stress and fatigue.

With

one-sided hearing the person won't hear well from the

affected side and may ask people to "stay on the

good side." Speech and noise will be heard only by

the good ear, making it harder to differentiate the

speech from the noise. It is also virtually impossible

for someone with unilateral hearing to localize a sound

because all sounds, regardless of direction, are heard in

the same place, the good ear. The stress and the fatigue

of having to use the one good ear constantly forces the

listener to work harder to hear well.

Research

indicates that unilateral hearing loss does have

significant effects on the person's ability to

communicate and psychosocial status. Individuals with

unilateral loss should make sure they receive appropriate

medical and audiological care.