Facts About Color Blindness

Color blindness is usually genetic, but can also be caused by traumatic injury or exposure to chemicals. There are three types of color blindness – one type makes it difficult to distinguish between red and green, the second type makes it difficult to distinguish between blue and yellow, and a third type is actually complete color blindness in which the eye cannot detect any colors at all. Red-green color blindness affects 10% of males in the United States, while only 0.5% of women are affected, and 99% of all people with color blindness have red-green color blindness.

Monochromacy is the name for total color blindness. It affects about 1 in 30,000 people. Unlike people with red-green or blue-yellow color “blindness,” people with monochromacy do not see any color at all, only varying shades of black, white, and gray. An English chemist named John Dalton, who was himself colorblind, published the first scientific paper on color blindness in 1798. In the retina (the light-sensitive tissue lining the back of the eye), there are two types of cells that detect light: rods and cones. Rods detect only light and dark and are very sensitive to low light levels. Cone cells detect color and are concentrated near the center of your vision. There are three types of cones that see color: red, green and blue. The brain uses input from these three color cone cells to determine our color perception.

Because a color vision problem can have a big impact on a person’s life, Color blindness is usually something that you have from birth but it can be acquired later in life. Change in color vision can signify a more serious condition. It is important to detect the problem as early as possible. In children, color vision problems can affect learning abilities and reading development. And color vision problems may limit career choices that require you to tell colors apart. Most experts recommend eye exams for children between ages 3 and 5. Vision screening is recommended for all children at least once before entering school, preferably between the ages of 3 and 4. Inherited color vision problems cannot be treated or corrected. Some acquired color vision problems can be treated, depending on the cause. For example, if a cataract is causing a problem with color vision, surgery to remove the cataract may restore normal color vision.

Anyone who experiences a significant change in color perception should see an ophthalmologist (Eye M.D.). Except in the most severe form, color blindness does not affect the sharpness of vision. The inability to see any color at all and to see everything only in shades of gray is called achromatopsia. This rare condition is often associated with amblyopia, nystagmus (involuntary, rapid eye movement), light sensitivity and poor vision. There is no known treatment. However, there are special contact lenses and glasses that may help people with color blindness tell the difference between similar colors. Color blindness is a lifelong condition. Most people are able to adjust to it without difficulty or disability. People who are colorblind may not be able to get a job that requires the ability to see colors accurately. For example, electricians (color-coded wires), painters, fashion designers (fabrics), and cooks (using the color of meat to tell whether it’s done) need to be able to see colors accurately.

Celeste Botonakis

On the Nursing Assistant Guides blog, certified medical assistant Celeste Botonakis explores the daily life of a CMA. She'll keep you up-to-date with the latest on what’s happening in the field, and provides tips for those who are interested in becoming a medical or nursing assistant. Celeste has served in the medical field for over six years, and is passionate about helping people. She currently works at CSR Primary Care in Skokie, Illinois. Click here to learn more about Celeste Botonakis and NursingAssistantGuides.com.