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Why do I get eye strain?
Shedding light on tired eyes
Maybe grandma wasn't right. Experts now contend that reading in the dark probably has no long-term damaging effects on the eyes. But eyes become more tired in poor light since they have to work harder to discriminate letters, colors, and objects. So it’s a good idea to work and play in plenty of light, especially as one gets older.
It's a sad fact with eyes that as one gets older, pupils get smaller. When you're older and wish to read with ease, it may take more light to illuminate the retina to the same level that it took to read with ease as a youth.
Opinion is divided as to whether or not regular eye exercises can strengthen the muscles in the eyes responsible for focusing. Eye exercises, also known as vision therapy, should only be undertaken on the advice and monitoring of an ophthalmologist or optometrist. Such vision therapy is usually intended for younger patients who have undeveloped or underdeveloped visual problems that may or may not involve specific eye muscles.
Some problems are perceptual in nature. The problem in middle age, when focusing on close objects becomes a strain, affects everybody at different times depending a host of factors. Some major factors include:
1. Refractive status of eyes (for example, nearsightedness (myopia) and other conditions),
2. Daily visual demands,
3. General health status and medications taken, and so on. The muscles responsible for focusing do not really change.
It is the transparent lens that actually gets less malleable with age. The chemical properties of the lens of the eye change and harden the lens that prohibits the lens from bending and changing thickness as easily. Human evolution is probably to blame for this as our prehistoric ancestors probably did not depend on eyes for close work nearly as much as we do.
Stephen Juan, Ph.D. is an anthropologist at the University of Sydney. Email your Odd Body questions to s.juan@edfac.usyd.edu.au