The ability to see colors can gradually lessen with age. Medications. Drugs used to treat heart problems, high blood pressure, infections, nervous disorders and psychological problems can affect color vision.Other causes for color vision deficiency include: Some diseases that can cause color deficits are: But disease or injury that damages the optic nerve or retina can also cause loss of color recognition. Usually, color deficiency is an inherited condition caused by a common X-linked recessive gene, which is passed from a mother to her son. It affects both eyes if it is inherited and usually just one if it is caused by injury or illness. Color vision deficiency can range from mild to severe, depending on the cause. People who are totally color deficient, a condition called achromatopsia, can only see things as black and white or in shades of gray. In both cases, people with color-vision deficiency often see neutral or gray areas where color should appear. This is a rarer and more severe form of color vision loss than just red-green deficiency because people with blue-yellow deficiency frequently have red-green blindness, too. This does not mean that people with this deficiency cannot see these colors altogether, they simply have a harder time differentiating between them, which can depend on the darkness or lightness of the colors.Īnother form of color deficiency is blue-yellow.

Most people with color vision deficiency can see colors. The most common form of color deficiency is red-green. But if the cones don't have one or more light-sensitive pigments, they will be unable to see all colors.

This enables us to distinguish countless shades of color. Normally, the pigments inside the cones register different colors and send that information through the optic nerve to the brain. The cones recognize these lights based on their wavelengths. Found in the macula (the central part of the retina), each cone is sensitive to either red, green or blue light (long, medium or short wavelengths). These cones have light-sensitive pigments that enable us to recognize color.

Color vision is possible due to photoreceptors in the retina of the eye known as cones.

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