Effects of Color Blindness on Boys
Why a Discussion On Colorblindness?
Colorblindness, also referred to as Color Vision Deficiency (CVD) or Color Vision Confusion (CVC), is a condition where a person is unable to see all colors accurately. It is estimated that 8% - 10% of the male population (11 million boys and men) in America has colorblindness. It is likely that at least one boy in a class of 20 suffers from colorblindness. In fact, our son was one of two boys who were colorblind in his kindergarten class.
Studies have shown that colorblindness can affect a child's learning experience and academic performance, particularly if they do not know that they have this condition. They suffer confusion, frustration, disappointment and teasing when they get the colors wrong. In some cases, this can cause behavioral problems.
In addition, people with colorblindness are barred from a number of occupations. It can be devastating for a person to work towards a career, only to find out that they cannot achieve their dream due to colorblindness.
For all of these reasons, it is very important to identify colorblindness at an early age. This section on color blindness is provided to increase awareness of how this condition can impact boys AND to give parents and teachers a glimpse at what their world is like.
What Causes Colorblindness?
Source: “Coping with Colorblindness” by Odeda Rosenthal and Robert H. Phillips, PhD
The retina has more than 130 million cells that act as receptors. These cells are called rods and cones, because they look like these shapes under a microscope.
The rods distinguish black from white. The cones translate different types of lightwaves into colors: cones that are sensitive to long wavelengths translate reds; cones sensitive to medium wavelengths translate yellow and greens; and cones sensitive to short wavelengths translate blues.
When the cones and rods function properly, the cones provide information about color and hue while the rods provide information about light, intensity or chroma. Colorblindness occurs when any of the rods or cones are missing or defective.
Although colorblindness is seen predominantly in males, it is estimated that 2% of females also suffer from this condition. Most people are born with this condition, and it is passed down through the mother’s genes. A woman whose father is colorblind will often pass this trait to her son.
For many years, scientists supported the Young-Helmholz theory that held that there was only one gene responsible for seeing colors. This changed when Doctors Jay and Maureen Neitz, leaders in color vision deficiency research, discovered that it was actually numerous genes that enabled color vision.
Doctors Jay and Maureen Neitz found that people with normal and abnormal color vision can have the same number of color vision genes (as many as ten), but not all the color vision genes are of equal strength. When some genes are more powerful than others, they drown out the rods and cones produced by the weaker genes.
These doctors concluded that color vision deficiency is caused by a mutation of genes or a lack of genes altogether. More importantly, their theory explained why people have varying levels of color vision deficiency. For this reason, they developed a simple color vision test that identifies both the type and severity of colorblindness. The tests require no training to administer and can be used on children as young as preschool age. A link to these tests is provided in the section: Recommendation for a Colorblindenss Test.
It is important to note that colorblindness can be acquired due to other factors. Here is a list of factors that can cause colorblindness [1]:
- Chronic Illnesses ( including Alzheimer’s disease, cataracts, whooping
cough, measles, diabetes, glaucoma, leukemia, Addison’s disease, pernicious
anemia, liver diseases, macular degeneration, multiple sclerosis, Parkinson’s
disease, retinitis pigmentosa and sickle cell anemia.
- Trauma that damages the head or eye.
- Glare of sun, snow or sea.
- Side effects of medication (including some antibiotics, barbiturates,
Benzedrine, contraceptive pills, digitalis glycosides (digoxin), Disulfiram,
Ethambutol Hydrochloride, Ethchlorvynol, Indomethacin, Lasix, Nitroglycerin
and Thorazine).
- Alcoholism and drug abuse.
- Industrical Toxins (including carbon disulfide, carbon monoxide,
fertilizers, bug sprays, antifreeze, lead and lead-based chemicals and
styrene).
- The natural process of aging
What does the World look like to the Colorblind?
Sources: Colorblind website by Doctors Jay and Maureen
Neitz; “Coping with Colorblindness” by Odeda Rosenthal and Robert H. Phillips,
PhD
No one will truly know what the world looks like to each colorblind
individual, but this section gives you and idea of what it is like.
First, let’s start with a visual. The link below will take you to a set
of slides that give you a glimpse at what the world looks like to a colorblind
child. These slides are provided by Doctors Jay and Maureen Neitz. As mentioned
above, these doctors are leaders in research on colorblindness.
Color
Blind World
More views of the Color
Blind World
People who have
full color vision are called trichromats. People who can only see two of the
primary colors of light are referred to as dichromats and those who can only see
black, white and grey are monochrats (these are very rare).
The largest
group of colorblind people are dichromats who have difficulty dealing with red
or green. Some people in this group do not have the cone to see red, so they see
red as black. Others have defective red cones and can see red but only as dark
brown or orange.
Dichromats with green color vision confusion (CVC) also
have defective or missing cones. If these cones are seriously defective, then
the person may see green as yellow, blue, white or orange. The book “Coping with
Colorblindness” tells a story of a boy with green CVC who was almost thrown out
of school for refusing to copy what the teacher wrote on the board. The
chalkboard was green and the chalk was yellow. These colors looked identical to
him, so he saw no words on the chalkboard!
Some individuals have a
combination of red and green CVC. For these people, green and red look alike;
orange-brown or purple-brown look like green and red. One French man with
red-green CVC couldn’t understand why so many American men wore pink pants (they
were actually khaki!). White wine looked like water to him and red wine looked
black. [1]
Dichromats with Blue CVC often have difficulty with yellow as
well. Blue and yellow often look like white or grey. Green is also difficult to
distinguish, since it is a combination of blue and yellow. This form of CVC is
uncommon, but is seen equally in males and females.
Dichromats with
Yellow CVC often mistaken yellow for white, grey, or black. And finally, people
with a combination of blue-yellow CVC see green as blue and blue as green. They
will often confuse blue and green, blue and violet, dark blue and dark red, and
light pastel colors.
Impact of Colorblindness on a Child
Sources: “Some
Psychological Aspects of Colour Blindness at School: A Field Study in Calabria
and Basilicata (Southern Italy)” by Doctor Grassivaro Gallo et al.; “Coping with
Colorblindness” by Odeda Rosenthal and Robert H. Phillips, Phd; “Colour
Blindness Causes and Effects” by Donald McIntyre
The biggest challenge
for a colorblind child (particularly if they are unaware of their condition) is
to reconcile what they perceive as “objective data” (their reality) versus what
people with normal vision are telling them. Their vision is telling them a fact
(the green chalk board has NO writing on it), while others are making statements
that totally contradict this (the chalkboard has writing in yellow
chalk).
When these children are unaware of their condition, they often
feel that they have made a mistake. When they fail to recognize colors
accurately by first grade, they are often assumed to be “slow”. In addition,
children with colorblindness must get used to occasional giggles about their
unusual color choices for their artwork.
A colorblind child’s color
choice for drawings can also be misinterpreted by teachers and parents. We often
associate black with mental or emotional disturbance. For a colorblind child,
black may be the safest color to use! Our son loved to use black in
kindergarten, and he continues to do most of his drawings in pencil or black
ink. At the beginning of every year, we tell the teachers that he is colorblind
and that it is ok if he doesn’t reach for the crayons or colored
pencils.
In many classrooms, color codes are used to provide contrast,
create interest and provide cues to help children learn. Colorblind children
miss out on these cues. Imagine being in a kindergartner with red CVC in a class
where the alphabet is featured as red letters for vowels and black letters for
consonants. This child sees ALL the letters as black. This child must struggle
to understand why the teacher is saying that the letters “a” and “b” have
different colors. You can imagine the frustration, especially if the child is
unaware of his/her condition.
Cuisenaire rods were popular tools for
teaching numbers in the 1960s. The color differences were useful to children who
could distinguish the colors. Colorblind children had to rely solely on the
length of the rods. They were at a significant disadvantage when the teacher
only referred to the rod by their color.
In addition, they do not get to
enjoy the advantages that color provides to the normal vision students. They
must memorize color names, even though they see subtle differences between them.
They may not see items on the wall that are highlighted in colors to bring
attention to them. They must accept that certain colors are associated with
holidays, even though there is little difference to them. The Christmas colors
of red and green are symbolic to many. To a child with red CVC, these colors can
look orange and black.
These difficulties do not end in the primary
grades. Older colorblind students can struggle in science and biology. As
demonstrated in the slides above, beakers with chemicals can appear to have no
color to a colorblind student. “Colored charts and maps are always a problem,
where there may be a legend of 10 or so colors to differentiate between
different areas” [2].
A colorblind teen learning how to drive may not be
able to distinguish the red and green lights at night. They must rely on the
position of the lights, which is much more difficult to see in the dark.
In
addition, many team sports use contrasting shirt colors to easily distinguish
the teams. These contrasting colors are useless to an individual who does not
see a difference in the colors.
With all of these struggles, it has been
found that some colorblind children do suffer psychologically. Interesting
findings were reported in the paper, “Some Psychological Aspects of Colour
Blindness at School: A Field Study in Calabria and Basilicata (Southern Italy)”
by Doctor Grassivaro Gallo et al. This paper was based on a mass screening for
colorblindness in schools. 63,933 male and female children were tested in 351
towns and in 655 secondary schools. In addition, 3,082 teachers of different
subjects were also given a questionnaire to analyze the school’s behavior
towards the colorblind students.
This study found that:
Helping colorblind students
In the book “Colour Blindness Causes and Effects”, the author presents some advice for teachers and parents. These recommendations were provided by an experienced teacher who addresses colorblindness in her class:
Look for Indications that a child may have colorblindness:
Teach with colorblindness in mind:
Colorblindness in Everyday Life
Sources: “Coping with Colorblindness” by Odeda Rosenthal and
Robert H. Phillips, Phd; “Colour Blindness Causes and Effects” by Donald
McIntyre
Color is used everywhere, so the challenges are numerous to a
colorblind individual. The simple act of selecting clothes becomes difficult and
may often require assistance.
Picking out ripe fruit is an everyday chore
for many of us. Imagine picking out ripe fruit when you can’t distinguish
between red and green. My son picks beautiful green apricots every year. We just
let them ripen on the counter. To him, they look perfectly orange.
Art,
home decoration and landscaping are all very difficult for the colorblind. In
the book “Color Blindness Causes and Effects”, the author tells of a person who
tried to purchase a plant with all dead leaves. The person could not distinguish
between the green and brown leaves. Fortunately, the checkout operator pointed
out the fact that the plant was dead.
Manufacturers and advertisers
constantly use color to distinguish products. Milk cartons feature different
colored ink to identify each milk type. Warning signs on chemical tanks have red
signs for flammable chemicals and green for non-flammable chemicals. This is
useful … if you can distinguish the colors.
Signs and websites use
contrasting colors to bring attention to information. Green lettering against an
orange background is easy for many people to read, but these letters are
completely lost to individuals with red-green colorblindness.
In the book
“Coping with Colorblindness”, the author tells of a man who was disturbed when
women wore makeup on their face. The makeup looked a shade of green to him.
Imagine seeing green blotches all over someone’s face. Imagine not being able to
see a sunburn on your body.
The book also tells of a boy who was afraid
to go to the bathroom during movies. The exit signs were red letters lit up on a
black background. Red looked black to him, so he could never see the exit signs.
Imagine what would happen in an emergency if you couldn’t see exit signs in the
dark.
Professions
that Require Full Color Vision
Sources: “Colour Blindness Causes
and Effects” by Donald McIntyre
There are numerous records of railway and
ship accidents as a result of colorblindness. In many of the cases, the
individual simply could not see that a red light was flashing. For this reason,
normal color vision has become a requirement for a number of professions.
Here is a brief list of some professions where colorblindness may be a
problem [2]: Armed forces, civil aviation, electronic and electrical
engineering, fire service (normal vision is required), motor mechanic, police,
railway, artistic work, beautician, buyer, cartographer, florist,
horticulturist, interior design, pharmacist and color photographer.
The
sad realty of colorblindness is that some professions will be unattainable by
anyone with this condition. Again, it is far better to know this before working
towards a desired career.
There are many anecdotal stories of people who
had no idea that they were colorblind. One boy spent his life dreaming of
becoming a pilot. He went to school and studied to be a pilot. During his
application into the Airforce, he was given a colorblindness test and was told
he would not be able to fly a plane.
In a very different case, a boy who
loved boats was told very early that he was colorblind. It was explained to him
that he would not be able to become a ship’s captain. Since he understood his
limitations, he pursued a career of mechanical engineer that specialized in the
mechanical aspect of ships. This knowledge allowed him to find an appropriate
career that followed his passion but was not restricted by his
colorblindness.
Recommendation for a colorblind test
It is important
that people understand that colorblind individuals see the world in a different
way. Their condition effects every aspect of their life: how they learn, how
they dress, how they drive, how they do their jobs, etc.
It is also
important to understand that there are varying types of colorblindness. This
means that two colorblind children in the same class may struggle with totally
different colors.
What I hope every reader walks away with is the
appreciation for how important it is to identify colorblindness at an early age.
It empowers a child to explain errors and ask for help. It allows parents to
inform teachers of the situation so that they can assist appropriately. Finally,
it prevents a young adult from pursuing a career that is ultimately
unattainable.
There are a number of tests for colorblindness. Ishihara
is the most popular and is often given at the doctor’s office. Unfortunately,
these tests are often given by untrained individuals, so it is good to go into
the test with an understanding of how the test should be administered. During
our son’s test, the nurse first tried to give the test under dim light. I had
to ask that the fluorescent lights be turned on. Then the nurse kept expressing
frustration when my son didn’t see the image. The nurse would say, “Are you sure
you don’t see the number 8 ?!” I exercised a lot of self control that day.
In
the end, the nurse turned to me and told me that our son had some kind of
red/green colorblindness. We had already figured that out when my son declared
that the grass was the same color as the hair on his redheaded sister! So
don't expect a lot of detail. You'll be present, though, so you'll be able
to see which plates were difficult for your child.
I strongly recommend
the Color Blind Tests developed by Doctors Jay and Maureen
Neitz. As explained in the above sections, these doctors are leaders
in colorblindness. They have developed a test that identifies the type of
color vision deficiency (which colors) and also the severity. The test requires
no training for administration, it only takes minutes to complete and it
can be administered to children as young as preschool age.
Your child is given
a sheet with various shapes against colors, similar to the Ishihara test.
Once the child is finished, a scoring key explains the type of colorblindness
and severity. You are able to keep the sheet for future reference.
Here is a link to these tests:
Click here for more information on the Neitz Test of Color
Vision.
These tests are meant to be sold to schools, so they sell the
tests in packages of 50. I encourage individuals to see if their school or
PTA will purchase these tests, so that school nurses can administer these
tests when a teacher suspects colorblindness.
There are a number of tests available
online, but these are not very reliable. Colors will appear differently on
screens, depending on how they have been calibrated. It is better to speak
to your doctor about having a colorblind test done in the office.
References and other useful
links:
The two books below were used as sources for this web
page. They are both excellent and contain much more detail than I was able
to cover.
[1] “Coping with Colorblindness” by Odeda Rosenthal and Robert H.
Phillips, Phd
[2] “Colour Blindness Causes and Effects” by Donald
McIntyre
[3] “Some Psychological Aspects of Colour Blindness at School: A
Field Study in Calabria and Basilicata (Southern Italy)” by Doctor Grassivaro
Gallo et al.
Doctor Grassivaro Gallo and her team have produced a number
of other papers on the impact of colorblindness on children. She is sending
those to me by mail. I will post results from these papers when I receive
them.
Neitz color vision web site
This is an excellent resource
for any parent or teacher who is trying to better understand this
condition.
What’s Color Blindness?
This is a GREAT webpage for kids
who know they are colorblind. It explains colorblindness to them.
“Color Vision – Almost Reason Enough for Having Eyes” (PDF
Format) by Jay Neitz, Joseph Carroll and Maureen Neitz
This also features
images of the colorblind world
Colorblindness – Topics in Usability
This site provides
information on how to select colors for web pages and other media that will
be legible to colorblind people.
Color
Vision Screening (PDF Format)
A Critical Appraisal of the Literature by
New Zealand Health Technology Assessment: this paper provides more details
on the impact of colorblindness on every day life.