Deafness is a partial or complete loss of hearing in one or both ears. A
child may be born with hearing loss or develop the problem later. As children
learn to talk by imitating others, a child who does not listen to others
talking not play these sounds.
Normal hearing occurs when sound waves pass through the ear canal and
cause the eardrum to vibrate. The vibrations of the eardrum, in turn, move
three small bones in the middle ear. The movement of these bones transmit the
vibrations of the middle ear to the inner ear, where they are transformed into
electrical impulses carried to the brain via the eighth cranial nerve. The
brain interprets these electrical impulses as sound. Damage, disease or
malfunction of any of these structures can cause deafness. Any of the following
problems may lead to hearing difficulties that are likely to lead to learning
difficulties.
Problems in the ear canal that can cause hearing loss include earwax
buildup, foreign object in the canal and infection known as otitis.
Problems in the eardrum and middle ear can be caused by an inflammation
of the middle ear or a blockage in the Eustachian tube, which connects the
throat and the middle ear. A middle ear infection (otitis media) occur within
the first two years of life, especially among children exposed to it frequently
in nurseries. The infection usually involve a fluid buildup that causes hearing
loss mild or moderate intermittent for up to nine months, threatening the
proper development of language skills of the child.
Problems of the inner ear can be caused by injury or infection.
As for the problems of the eighth cranial nerve have many possible
causes. This nerve is responsible for transporting all signals from the ears
and brain equilibrium structures. A child may be born with a nerve that has not
developed properly or has been damaged before birth. For example, if a pregnant
woman contracts rubella virus may infect the fetus of the eighth cranial nerve.
After birth injury or infection with viruses (mumps or measles) or bacteria
(meningitis) that may damage nerve. There are also certain medications that can
affect you.
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