Color Blindness - Color Vision Deficiency

Color Blindness (Color Vision Deficiency)

When we talk about color blindness or for the more appropriate term color vision deficiency, most people without knowledge of the subject would assume that all color blind people see the world in black and white. There are three different kinds of color vision defects which are the red-green and blue-yellow and the total complete absence of color vision. About 8% of males possess color vision problems and less than 1% of females have this problem for red-green color vision deficiency and blue-yellow color vision deficiency occurs less than one in ten thousand people. Color blindness can be acquired at birth or even at a later age.

Color vision deficiency is not the case where an individual have the inability to see a certain color, it is actually the inability of the individual to differentiate certain shades of certain colors. Severe cases where black and white or gray colors can only be seen by the person are called ‘Achromatopsia’. Achromatopsia or day blindness is interesting as it is a very different condition as to the common red-green and blue-yellow color vision deficiency and it is estimated that one in thirty thousand people are affected by Achromatopsia. It is non-progressive, meaning the condition does not get any worse and is a heredity visual disorder and its symptoms are light sensitivity, decrease in vision and total absence of color vision. In some cases nystagmus, shaking of the may be present and some may have partial day blindness in which case they can see better.

The cause of this condition is by the abnormality of the retina. In the retina contains three different cells responsible for color vision. There are the red, green and blue cones and if these cones aren’t functioning they cause Achromatopsia and partial Achromatopsia is cause reduced or imbalance cones. Only four genes are found responsible for this condition which is chromosome 14, 8q21-q22, 2q11 and 10q24. There is a 25% chance of a child developing Achromatopsia through autosomal recessive inheritance and a 50% chance of a unaffected child being a carrier of the disease. In this time and date there is no cure for this condition, people with this condition cope by prescribing glasses, wearing tinted or red color lens to reduce light sensitivity. Currently there is a device which allows the user to see colors by sound waves; this device is call the eyeborg.

Red-green and blue-yellow color vision deficiency involves the retina and the color cones as well. Pigments inside the cones register different colors and send the information to the brain enabling the ability to distinguish different shades of color. However when the cones lack one or more light sensitive pigments, the person won’t be able to see the primary colors properly, thus causes a deficiency in color perception and lack having the ability to differentiate between certain colors. The intensity