Color Deficiency FAQ's
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What is color deficiency?
Color Deficiency occurs when your ability to distinguish
certain colors and shades is less than normal. The term "color blind"
is often used, but usually incorrectly. Only a small number of people are
completely unable to identify any colors.
What causes color deficiency?
Color Deficiency is usually inherited, but can also result
from certain medications. It happens when the color sensitive cone cells in the
retina of your eyes do not properly pick up or send correct color signals to the
brain.
What types of color deficiency exist?
There are two major types. Red-green deficiency is by
far the most common and results in the inability to distinguish certain shades
of red and green. Blue-yellow deficiency is less common and affects the
perception of blue and yellow colors.
In very rare cases, color deficiency exists to an extent
that no colors can be detected. This person sees all things in shades of black,
white and gray.
How is color deficiency detected?
People who are color deficient are often unaware of their
condition. They assume that everyone sees things the way they do.
As a result, a complete optometric examination, including
a test for color vision, is recommended. A test for color deficiency is
relatively simple and typically involves viewing a series of colored designs or
objects.
The designs have been created in such a way that a person
with normal color vision can see certain figures in the design. A color
deficient person will not be able to distinguish the figures.
When should a person be tested for color deficiency?
Every child should be checked for color deficiency by at
least age five. It is important to detect color deficiency early because color
coded learning materials are used extensively in the primary grades.
In addition, color deficiency may affect the career path
of an individual, since the ability to distinguish colors is an important aspect
of some jobs, such as pilots, electricians, some military personnel, police
officers, and others.
Can color deficiency be cured?
Unfortunately, a cure for color deficiency has not yet
been discovered. A person with color deficiency can, however, be taught to adapt
to the inability to distinguish colors. For example, you can be taught to
recognize the brightness and location of a traffic light rather than the color
itself.
It is sometimes possible to distinguish colors with the
use of special filters. A special red tinted contact lens, used in one eye, and
other devices are used, in some cases, to aid persons with certain color
deficiencies.
Compliments of:
American Optometric Association
Visit the AOA World Wide Web site at:
www.aoanet.org/aoanet
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