Ever since Eric was small, he knew he was different from the other kids. They made fun of him because his clothes never looked right together, and he had trouble following the directions for putting toys in the correct bins at school or joining the right team during gym class. What they didn’t understand was that everything in their world was sorted or matched by color, and Eric is color blind.
Now in his twenties, Eric has learned to compensate for his color vision deficiency, but it took time and patience to master some of the skills he needed to cope with everyday tasks many others complete without a second thought. “Digital readouts with green or red LED are a problem, and so are appliances and controls with red and green lights and buttons. I can’t tell you how many charts and graphs I couldn’t read properly because they were color-coded,” he says. “And I can never tell when I’m starting to get a sunburn!”
Healthy human eyes see three colors, red, blue, and green. Specialized nerves in the retina called rods and cones (named for their shapes) help us see. Rods are highly sensitive and help your eyes to adjust to various levels of light and identify basic shapes. Cones work best in bright light and provide fine detail and color. Issues with the cone cells are the cause of color blindness. Cones identify colors and transmit signals to the brain, which are then converted into full-color vision. People with fully functioning cones can see all three colors in a wide variety of combinations, allowing a full spectrum of color vision. This is called trichromacy, or normal vision. Decreased color vision comes in three basic types, red/green, blue/yellow, or monochromacy, a total lack of color vision.
Eric has the most common form of color blindness, a deficiency in seeing red and green colors. What Eric sees is a world of muddy green with hints of blue and yellow. He has trouble differentiating browns, oranges, and reds, and almost all pale shades look the same. Blue/yellow color blindness is much less prevalent, causing an inability to tell the difference between blue and green, or between yellow and red. Monochromacy is a very rare condition where people see the world as a classic movie from the 1930’s – all black, white, and gray.
Eric’s color blindness is inherited – he was born with it. The genes that establish correct cone function are passed from parents to children, and the particular genes Eric received have an error causing diminished cone function. Color blindness runs in his family; he has six other close family members with the condition. Males have one X chromosome and one Y chromosome (XY), and females have two X chromosomes (XX). Boys get their single X chromosome from their mothers. If that chromosome has the genes for red-green color blindness, they will be born with the condition. Girls inherit two X chromosomes, one each from their mother and father. Both their mother and father have to carry the genes for red-green color blindness before they can pass it to their daughters, making girls less likely to inherit the condition. Blue/yellow color blindness, which has a different genetic component, is passed along equally to male and female children.
It is possible to develop color blindness as well. Some of the most common causes of acquired colorblindness are:
- Eye injuries
- Eye diseases (glaucoma and macular degeneration)
- Nervous system diseases such as Parkinson’s, Alzheimer’s, or multiple sclerosis
- Medications such as tiagabine (an anti-seizure drug) and Plaquenil (for rheumatoid arthritis and other autoimmune diseases)
- Environmental pollutants
- Age can cause slight blue/yellow color blindness. As the lens of the eye becomes less transparent, less light reaches the cones.
- Alcohol consumption can reduce color presentation, again mostly affecting blue/yellow perception.
- Brain trauma such as head injury or stroke can infrequently result in color blindness.
Inherited forms of color blindness are not curable. As a genetic condition, the only possible way to reverse it would be through gene therapy. At this point, tests are underway in labs that may eventually lead to the ability to reverse inherited color blindness, but those success stories are still in their infancy. Some types of acquired color blindness can be treated by addressing the underlying condition.
However, technology is making strides to assist the colorblind with managing their condition. Colorblind contacts or colorblind glasses can offset color blindness. Introduced in 2010, market leader EnChroma pioneered glasses that can increase color contrast and enable some people to achieve better color vision. EnChroma glasses normally cost $250 to $350 per pair. There are also apps available that can assist with color identification. Try one of these:
Color Blind Pal - Touch a spot on a picture and the color name of that point is displayed. If people with normal vision want to see what it's like to be color blind, the app can also provide this experience. The app will not only provide color names, it also has a Color Inspector that describes the color to help those who are color blind visualize the shade.
ColorBlind Helper will identify colors for people with color deficiencies. Take a photo of an object or scene, touch a spot on the picture, and the app will display the color name, RGB composition, or hexadecimal code of the point indicated. At last count, the database had stored about 1,500 color names.
ColorDeBlind is designed for people who are color deficient, as well as others who would like to see the world as color deficient people do. It uses the graphics processor within your device to run advanced color manipulation algorithms, which better distinguish colors.
Visolve makes certain colors in a photo taken by the camera (or saved in the photo album) brighter or darker. For example, if you have trouble distinguishing between red and green, Visolve can make the redder colors brighter or darken all colors except the selected color. You can also add different hatch patterns to certain colors or increase the saturation of all the colors in the image.
A vision test given by a qualified optometrist is the best way to diagnose color blindness. At Pro-Optix Eye Care, we perform dozens of these important tests each month. You can trust your Houston eye doctor to provide the best advice for living a colorful life while experiencing color vision deficiency. Don’t wait - call 713-360-7095 today to book your vision exam!