Color
Blindness
Overview
Color blindness — or more
accurately, poor or deficient color vision — is an inability to see the
difference between certain colors. Though many people commonly use the term
"color blind" for this condition, true color blindness — in which
everything is seen in shades of black and white — is rare.
Color blindness is usually
inherited. Men are more likely to be born with color blindness. Most people
with color blindness can't distinguish between certain shades of red and green.
Less commonly, people with color blindness can't distinguish between shades of
blue and yellow.
Certain eye diseases and
some medications also can cause color blindness.
Symptoms
You may have a color vision
deficiency and not know it. Some people figure out that they or their child has
the condition when it causes confusion — such as when there are problems
differentiating the colors in a traffic light or interpreting color-coded
learning materials.
People affected by color
blindness may not be able to distinguish:
Different shades of red and
green
Different shades of blue and
yellow
Any colors
The most common color
deficiency is an inability to see some shades of red and green. Often, a person
who is red-green or blue-yellow deficient isn't completely insensitive to both
colors. Defects can be mild, moderate or severe.
When to see a doctor
If you suspect you have
problems distinguishing certain colors or your color vision changes, see an eye
doctor for testing. It's important that children get comprehensive eye exams,
including color vision testing, before starting school.
There's no cure for
inherited color deficiencies, but if illness or eye disease is the cause,
treatment may improve color vision.
Causes
Seeing colors across the
light spectrum is a complex process that begins with your eyes' ability to respond
to different wavelengths of light.
Light, which contains all
color wavelengths, enters your eye through the cornea and passes through the
lens and transparent, jellylike tissue in your eye (vitreous humor) to
wavelength-sensitive cells (cones) at the back of your eye in the macular area
of the retina. The cones are sensitive to short (blue), medium (green) or long
(red) wavelengths of light. Chemicals in the cones trigger a reaction and send
the wavelength information through your optic nerve to your brain.
If your eyes are normal, you
perceive color. But if your cones lack one or more wavelength-sensitive
chemicals, you will be unable to distinguish the colors red, green or blue.
Color blindness has several
causes:
Inherited Disorder. color deficiencies are much more common in
males than in females. The most common color deficiency is red-green, with
blue-yellow deficiency being much less common. It is rare to have no color
vision at all.
You can inherit a mild,
moderate or severe degree of the disorder. Inherited color deficiencies usually
affect both eyes, and the severity doesn't change over your lifetime.
Diseases.
Some conditions that can cause color deficits are sickle cell anemia, diabetes,
macular degeneration, Alzheimer's disease, multiple sclerosis, glaucoma,
Parkinson's disease, chronic alcoholism and leukemia. One eye may be more
affected than the other, and the color deficit may get better if the underlying
disease can be treated.
Certain medications.
Some medications can alter color vision, such as some drugs that treat certain
autoimmune diseases, heart problems, high blood pressure, erectile dysfunction,
infections, nervous disorders and psychological problems.
Aging. Your ability to see
colors deteriorates slowly as you age.
Chemicals.
Exposure to some chemicals in the workplace, such as carbon disulfide and
fertilizers, may cause loss of color vision.
P.S. Dwight
Eugene Gooden (born November 16, 1964), nicknamed "Dr. K" and
"Doc", is an American former professional baseball pitcher who played
16 seasons in Major League Baseball (MLB). Gooden pitched from 1984 to 1994 and
from 1996 to 2000 for the New York Mets, New York Yankees, Cleveland Indians,
Houston Astros, and Tampa Bay Devil Rays. In a career spanning 430 games, he
pitched 2,800+2⁄3 innings and posted a win–loss record of 194–112, with a 3.51
earned run average (ERA), and 2,293 strikeouts.
He will be 58 years old on November 16th.
Jan Ricks Jennings, MHA,
LFACHE
Senior Consultant
Senior Management Resources,
LLC
JanJenningsBlog.BlogSpot.com
724.733.0509 Office
412.913.0636 Cell
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