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Sciences of
Music
Silent Music
Types
There are four kinds of hearing loss: The first is conductive
hearing loss. It is caused by diseases or obstruction in the outer
or middle ear but is usually not severe. A person with conductive
hearing loss can be cured with a hearing aid or corrected with
through surgical or medical treatment.
The second kind of deafness is sensorineural hearing loss. It comes
from damage to the sensory hair cells or the nerves in the inner
ear and can range in severity from little to extreme deafness. A
hearing aid may not help a person with a sensorineural
loss.
The third kind is mixed hearing loss. It is caused by problems in
both the outer or middle ear and the inner ear.
The last is central hearing loss. That is the result of damage to
or impairment of the nerves or nuclei of the central nervous
system.
Schooling
Deafness does not affect a person's intellectual capacity or
ability to learn. A child who sustains a hearing loss early in
life, however, may lack the language stimulation experienced by
children who can hear. A delay in learning language may cause a
deaf child's academic progress to be slower than that of hearing
children. So a deaf adolescent may be four or more grade levels
behind his or her hearing peers. But deaf children who receive
early language stimulation through sign language, however,
generally do well academically.
Today, by the age of four or five, most deaf children are enrolled
in school on a full-day basis. Approximately one-third of the
population of school-age deaf children attend private or public
residential schools. The rest live at home and attend day programs
in schools for the deaf or special day classes in regular
schools.
Communication for the deaf
People who are deaf canít talk because they canít hear
the speech so they come up with other ways to communicate. One is
Finger spelling. That is a system in which hand shapes and
positions correspond to the letters of the written alphabet. In a
very real sense, finger spelling can be called "writing in the
air.î Sign Language is another. The language based on gestures
and grammatical rules that share some common points with English.
Another is Cued Speech, which is a system in which eight hand
movements indicate the pronunciation of every syllable being
spoken. It is a speech-based method that supplements lip-reading.
Hearing aids
A hearing aid is an electronic device that amplifies sounds for
persons with hearing impairments. A hearing aid has a microphone, a
amplifier (consisting of transistors and integrated electronic
circuits), miniature receiver, and a battery of a hearing aid which
are enclosed either in a chassis or shell, That is worn behind or
within the ear or in the stem or temple portion of eyeglasses. A
small tube directs the amplified sound from the receiver into the
ear canal of the wearer. People with severe hearing
impairments require a more powerful amplifier. It is usually
encased in a chassis smaller than a package of cigarettes, which
can be easily carried in a shirt pocket. A cord connects the
amplifier to the receiver in the wearer's ear.
Most hearing aids have adjustable controls which lets the
wearer control how much it amplifies the sound by.
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