Audiology
Hearing
Types of Hearing Loss
Hearing loss is caused by damage to one or more of the ear's
three regions:
- External ear, pinna, and ear canal
- Middle ear, which is separated from the ear canal by the eardrum
- Inner ear, which contains the cochlea, the main sensory organ of hearing
There are three main types of hearing loss, characterized by which part of the ear is damaged. These include:
There is also another area of hearing that can
be affected, called
Auditory Processing Disorder (APD), which is
characterized by those individuals that hear well but do not process
what they
hear normally.
Conductive Hearing Loss
In conductive hearing loss,
disorders in either the outer or middle ear prevent sound from
passing into the inner ear. Voices and sounds may sound faint,
distorted, or both. Conductive hearing losses are most often
seen in young children, but they can also be seen in some adults.
Most conductive hearing loss can be improved medically or surgically
if treated
promptly.
Causes of conductive hearing loss include:
- Infection of the ear canal or middle
ear
- Fluid in the middle ear
- Perforation or scarring of the eardrum
- Ear wax (cerumen) build-up
- Dislocation of the three middle-ear bones, called ossicles
- Foreign objects in the ear canal
- Otosclerosis (abnormal growth
of bone in the middle ear)
- Unusual growths in the outer or middle ear
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Sensorineural Hearing Loss
In people who have sensorineural
hearing loss, sound is efficiently sent to the inner
ear, but some sort of damage to the inner ear interferes with
proper hearing.
This
type
of
hearing
loss occurs when there is either damage to the inner ear structures
or the hearing nerve.
Sensorineural hearing loss is the most common type of hearing
loss among adults It usually is not medically or surgically treatable,
but can be treated successfully with hearing
aids. Those who suffer from sensorineural hearing loss may
complain that people seem to mumble, or that they hear—but
don't understand—what is being said. Aging is the
most common cause of sensorineural hearing loss. As we get older,
the sensory cells of the inner ear gradually die. Learn
more about aging and hearing loss.
In addition to advancing age, sensorineural hearing loss can be caused by:
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Mixed Hearing Loss
If a hearing loss has both a conductive and
a sensorineural component, it is referred to as a mixed hearing
loss.
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Auditory Processing
Disorder (APD)
Hearing problems may also result from a central
auditory processing disorder—a neurological problem that
may be inherited or caused by complications during pregnancy,
birth, or a combination of causes, such as head trauma, disease,
tumor, and lead exposure, to name just a few. People with APD
usually have normal hearing when taking traditional hearing
tests,
but
they
are unable
to process speech effectively in everyday situations (classrooms,
workplaces, community gatherings, etc.)
Learn more APD
Learn More
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