Melanin provides the signal that indicates which fibers should cross over and which should not. In a normal-sighted eye, the optic nerve (which connects the eyeball to the brain) includes some fibers that stay on one side of the brain and some that cross over to the other.How does a lack of pigment affect the eyes? This is a complex question because it affects the eyes in several ways: Typically, they will move their head to the position necessary to focus on this spot, consequently slowing their nystagmus, and allowing for their best vision. Because a person with albinism has an underdeveloped fovea, they must find their best area of focus, which may be anywhere on their retina. Their fovea is where they focus for their best detail vision – such as seeing a freckle on a person’s face. In normal-sighted people, the fovea is in the center of the macula and an image will land there when the person is looking straight ahead. What is the “null point”? People with albinism have a poorly developed fovea. In fact, they often will find a “null point” which is the point where their nystagmus is the least apparent.ħ. Does nystagmus affect vision? Although people with nystagmus are not aware their eyes are moving, it does make it more difficult for them to focus clearly on details. It tends to increase when the person is upset, excited or tired.Ħ. Nystagmus is present to varying degrees in people with albinism and typically declines with age. The involuntary eye movements may be from side-to-side, up and down, or rotary. What causes the irregular eye movements? This is a condition called nystagmus. In fact, with some forms of albinism, vision may actually improve slightly throughout childhood.ĥ. Albinism is a non-degenerative retinal condition, which means it does not worsen with time (other than the “normal” changes that occur with age and are correctable with glasses). Will their vision get worse over time? No. One great description we found was “not blurry as it would be for nearsighted people, but lacking in clarity and detail, like a photograph with low resolution.” Most people with albinism are able to distinguish colors.Ĥ. What can they see? It’s difficult to say. However, this is quite different from total blindness.ģ. People with albinism may be “legally blind” which is defined as vision that is not correctable to better than 20/200. Their vision may vary from 20/40 to 20/400. This typically affects the skin, hair and eyes.Ģ. What is albinism? Simply put, albinism is a decrease in or absence of melanin, the protein necessary for pigmentation.
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