JEANNE SOLOMONS, LONDON, ENGLAND: My name is Jeanne Solomons. I'm from London, the United Kingdom. And my question is, WHY IS IT, WHEN YOU GET TO A CERTAIN AGE, YOUR EYESIGHT DETERIORATES?</s>DR. DOYLE STULTING, PRESIDENT OF OPTHAMOLOGY, EMORY UNIVERSITY: Your viewer is probably asking about the gradual loss of near vision that occurs with aging. We call this condition presbyopia. At about the age of 45, this becomes noticeable when objects at normal reading distances become blurred. The normal human eye focuses parallel rays of light from distant objects on the retina. As objects are moved closer to the eye, the focal point moves behind the retina. So the lens inside the eye must change it's dimensions and increase its power in order to move the focal point back onto the retina. As we age, the lens loses its ability to focus near objects because it becomes stiff.
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