Soaking Up the Whole World @ Explorers Adventure Academy The World is Our Classroom!: Life-Living with a Color Defenciecy in a Colorful World!!

What is it like to be color deficient?

What Is Colorblindness and the Different Types?

The human eye sees by light stimulating the retina (a neuro-membrane lining the inside back of the eye). The retina is made up of what are called Rods and Cones. The rods, located in the peripheral retina, give us our night vision, but can not distinguish color. Cones, located in the center of the retina (called the macula), are not much good at night but do let us perceive color during daylight conditions.

The cones, each contain a light sensitive pigment which is sensitive over a range of wavelengths (each visible color is a different wavelength from approximately 400 to 700 nm). Genes contain the coding instructions for these pigments, and if the coding instructions are wrong, then the wrong pigments will be produced, and the cones will be sensitive to different wavelengths of light (resulting in a color deficiency). The colors that we see are completely dependent on the sensitivity ranges of those pigments.

Many people think anyone labeled as "colorblind" only sees black and white - like watching a black and white movie or television. This is a big misconception and not true. It is extremely rare to be totally color blind (monochromasy - complete absence of any color sensation). There are many different types and degrees of colorblindness - more correctly called color vision deficiencies.

People with normal cones and light sensitive pigment (trichromasy) are able to see all the different colors and subtle mixtures of them by

using cones sensitive to one of three wavelength of light - red, green, and blue. A mild color deficiency is present when one or more of the three cones light sensitive pigments are not quite right and their peak sensitivity is shifted (anomalous trichromasy - includes protanomaly and deuteranomaly). A more severe color deficiency is present when one or more of the cones light sensitive pigments is really wrong (dichromasy - includes protanopia and deuteranopia).

5% to 8% (depending on the study you quote) of the men and 0.5% of the women of the world are born colorblind. That's as high as one out of twelve men and one out of two hundred women. I am going to limit this discussion to protans (red weak) and deutans (green weak) because they make up 99% of this group.

Protanomaly (one out of 100 males):
Protanomaly is referred to as "red-weakness", an apt description of this form of color deficiency. Any redness seen in a color by a normal observer is seen more weakly by the protanomalous viewer, both in terms of its "coloring power" (saturation, or depth of color) and its brightness. Red, orange, yellow, and yellow-green appear somewhat shifted in hue ("hue" is just another word for "color") towards green, and all appear paler than they do to the normal observer. The redness component that a normal observer sees in a violet or lavender color is so weakened for the protanomalous observer that he may fail to detect it, and therefore sees only the blue component. Hence, to him the color that normals call "violet" may look only like another shade of blue.

Color normal Color Deficient Dichromat

(source: critiquewall.com by Paul Martin)

Under poor viewing conditions, such as when driving in dazzling sunlight or in rainy or foggy weather, it is easily possible for protanomalous individuals to mistake a blinking red traffic light from a blinking yellow or amber one, or to fail to distinguish a green traffic light from the various "white" lights in store fronts, signs, and street lights that line our streets.

Deuteranomaly (five out of 100 males):
The deuteranomalous person is considered "green weak". Similar to the protanomalous person, he is poor at discriminating small differences in hues in the red, orange, yellow, green region of the spectrum. He makes errors in the naming of hues in this region because they appear somewhat shifted towards red for him. One very important difference between deuteranomalous individuals and protanomalous individuals is deuteranomalous individuals do "not" have the loss of "brightness" problem.

From a practical stand point, many protanomalous and deuteranomalous people breeze through life with very little difficulty doing tasks that require normal color vision. Some may not even be aware that their color perception is in any way different from normal nor do their friends. The only problem they have is passing that "Blank Blank" color vision test.

Dichromasy - can be divided into protanopia and deuteranopia (two out of 100 males):
These individuals normally know they have a color vision problem and it can effect their lives on a daily basis. They see no perceptible difference between red, orange, yellow, and green. All these colors that seem so different to the normal viewer appear to be the same color for this two percent of the population.

Protanopia (one out of 100 males):
For the protanope, the brightness of red, orange, and yellow is much reduced compared to normal. This dimming can be so pronounced that reds may be confused with black or dark gray, and red traffic lights may appear to be extinguished. They may learn to distinguish reds from yellows and from greens primarily on the basis of their apparent brightness or lightness, not on any perceptible hue difference. Violet, lavender, and purple are indistinguishable from various shades of blue because their reddish components are so dimmed as to be invisible. E.g. Pink flowers, reflecting both red light and blue light, may appear just blue to the protanope.

Deuteranopia (one out of 100 males):
The deuteranope suffers the same hue discrimination problems as the protanope, but without the abnormal dimming. The names red, orange, yellow, and green really mean very little to him aside from being different names that every one else around him seems to be able to agree on.

In Conclusion:
It should be obvious there are several different kinds and degrees of color vision deficiencies. Protanomalous or deuteranomalous individuals can usually pass as a normal observer in everyday activities. They may make occasional errors in color names, or may encounter difficulties in discriminating small differences in colors, but usually they do not perform very differently from the normal except on color vision tests.
The protanope and deuteranope, on the other hand, can be severely color deficient. The real problem, as a protanope or deuteranope may see it, is there are far too many hue names (color names) used by most people without any obvious basis for using one instead of another. Why call something "orange" when it doesn't look different in any way from something else called green, tan, beige, or any of several other color names?

Click here for an excellent Powerpoint presentation by Dr. Rabin on colorblindness. The presentation is technical and mainly for the scientific community.

What Teachers, School Nurses, and Parents, Should Know About Being Colorblind" by Dr. Terrace L. Waggoner

Today, having normal color vision or being colorblind, plays a big part in our educational system. We not only have to learn our colors but color-enhanced instructional materials have become common place throughout the classroom. To see a sample of color-enhanced instructional material (click here). It is important that the educational system and parents understand the special needs of color deficient children and what can be done to help them in their quest to learn.

For some color deficient individuals, the names red, orange, yellow, and green are simply different names for the same color. The same is true for violet, lavender, purple, and blue. Among the colors most often confused are pink/gray, orange/red, white/green, green/brown, blue green/gray, green/yellow, brown/maroon, and beige/green. Pastels and muted tones are difficult to distinguish. The color vision defect may be so bad that the affected person cannot distinguish brown socks from green socks, a red traffic light from an amber one, or green grass from brown soil by color alone.

Examples of how the condition can cause problems at school.

1. John is working in his reading workbook. The directions to one item say to draw a line to the red ball. The other ball is brown. Both colors look alike to John, so he guesses. The teacher reminds him not to be careless.
2. A teacher is writing vocabulary words on a green chalk board with yellow chalk in mid-afternoon. There is a glare on the board from unshaded windows. Peter is sitting so that the glare diminishes the figure-ground contrast. The teacher wonders why he is copying from a neighbor's paper.
3. Tommy ordinarily seems to enjoy reading aloud. Today, however, he doesn't volunteer and balks when the teacher calls on him to read. The poem in the reader is printed in blue on a purple background.
4. Susan, a bright and articulate youngster, was asked to go to the front of the class and read from the blue green book on the teachers' desk. She went to the front of the class and just stood there looking at the pile of different colored books. Not knowing which one to pickup, she started to cry.
5. T.J. was very out going in pre-school & kindergarten. He loved to wave his arms and volunteer to answer questions the teacher asked. The only time he did not volunteer answers was when it came to learning or identifying his colors. A lot of the colors looked the same to him. They just had different names.
6. The kindergarten teacher notices the kids during art class teasing Jimmy. The other kids think it is funny that Jimmy's stick people have green faces.

Color Normal Color Deficient

(source: critiquewall.com by Paul Martin)

7. The kids at school told the teacher Jeff was cheating during kick ball. They said he would break the rules by kicking the ball when it was out of bounds. They accusingly stated the boundary lines on the green grass were clearly marked with orange chalk. Jeff, rather than admitting he could not see the boundary line, simply quit playing with the other kids during recess.

How can teachers help if a child has a color deficiency?

a. Label a picture with words or symbols when the response requires color recognition.

b. Label coloring utensils (crayons, colored pencils, and pens) with the name of the color.

c. Use white chalk, not colored chalk, on the board to maximize contrast. Avoid yellow, orange, or light tan chalk on green chalkboards.

d. Xerox parts of textbooks or any instructional materials printed with colored ink. Black print on red or green paper is not safe. It may appear as black on black to some color deficient students.

e. Assign a classmate to help color deficient students when assignments require color recognition. Example - color coding different countries on a world map.

f. Teach color deficient students the color of common objects. Knowing what color things are can help them in their daily tasks. Example: when asked to color a picture, they will know to use the crayon "labeled" green for the grass, blue for the sky, and light tan for Lincoln's face.

g. Try teaching children "all" the colors. Remember, most color deficient children can identify pure primary colors. It is normally just different shades or tints that give them problems. If they can not learn certain colors, let them know you understand some colors look the same to them and it is "OK".

h. Make sure a child's color vision has been tested before they have to learn their colors or color-enhanced instructional materials are used.

Please feel free to to print or make a copy of this article for your school. I found the below article on the Internet at http://ehow.com by Mollycarter. She repeated much of what I recommended but added to it. I cut and pasted it because I like what and how she wrote it.

How to Help a Colorblind Child in the Classroom

Step 1

Use white chalk on the chalkboard. Although some teachers prefer yellow or pink chalk, against a green chalkboard, these colors are sometimes hard for a colorblind child to see, especially if there is a glare. Always use white chalk.

Step 2

Xerox all textbook and educational items that are colored in black and white. Although a child cannot separate the items on paper, by copying them in black and white they will be able to see all the different sections properly. Always Xerox on white paper.

Step 3

Teach colorblind students the colors of common items. Oranges are orange. The sun is yellow. Although the student will not be able to see the differences, they will have a frame of reference when people are discussing colors.

Step 4

Be patient with colorblind students on classroom activities. It’s easy to get frustrated or think a child is not trying when they guess on certain activities. If a child has not been diagnosed, yet you see them panicking when asked to work with pie charts or color coded maps, insist that child be tested for color blindness.

Step 5

Stop color-coding items, or write the color below it. Do not use color-coding for paperwork, classroom items, or on homework or testing. If you do, write the color below.

Step 6

Help a child with standardized tests. Standardized tests are not colorblind friendly. If there are charts or color-coded items, write out the colors below the appropriate colors so the child will not be at a disadvantage.

Step 7

Label all craft items that have color like markers, crayons and paper. So the child will not fall behind in art, or struggle, make sure everything is appropriately marked.

Step 8

Teach what colorblindness is. Children who do not suffer from colorblindness will have a hard time understanding what it is. There are tests you can use to show a child how things look to a child that sees normally versus a child that cannot see all colors properly.