The last section covered three additional ways
Deaf people communicate besides sign languages. Just as not all Deaf people use
the same methods of communication, not all Deaf people have the same cause
of deafness. Earlier, we briefly discussed the categorizations of deafness but now we
are going to look at specific causes. Usher Syndrome is a genetic disorder leading to
deafness and blindness. There are three types of Ushers and all are autosomal recessive. This means
for a person to expr
ess Usher s Syndrome they need to receive the recessive gene from BOTH parents.
Since it is a recessive gene, neither parent may express Ushers, they have a dominant, non-Ushers
gene and are carrying the recessive gene. Deafness is going to be sensorineural meaning
the cause of deafness is related to the cochlea or the auditory nerve. Blindness is caused by
retinitis pigmentosa, this affects the retina, the tissue at the back of the eye. This type of
blindness is a process, meaning the baby
will be born sighted but as they get older they will
start to lose their night vision. This is the eye s ability to take in low levels of light and allow
sighted people to see some things in the dark. Then as the person grows older, they
lose sight in their peripheral vision, this is the part of vision where you focus on
something in front of you but you can still see your hands if you hold them up to the
sides of your face. These new blind spots enlarge over time and eventually merge
lea
ving the person with tunnel vision. Tunnel vision is a type of blindness where the
person s field of vision is as if you are standing in a tunnel. Everywhere around you is black except
for the light coming in from the distance. There are three types of Usher Syndrome.
Type 1 is when the person is born deaf and blindness begins in childhood.
Type 2, the person is born deaf but blindness begins in adolescence, when
they are a teenager, or in adulthood. Type 3, the person is born hearing and t
hey become
deaf and blind in childhood or adolescence. When meeting a person with Usher Syndrome it is
important to note their tunnel vision. Remember to stand in front of them when signing. If you
need to get their attention, you will need to access their field of vision, waving your hand in
their peripheral will not work because they cannot see you. However, once you are in their field of
vision, they will be able to see your signs.
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