The Sun Is the Best Optometrist – NYTimes.com.
Researchers suspect that bright outdoor light helps children’s developing eyes maintain the correct distance between the lens and the retina — which keeps vision in focus. Dim indoor lighting doesn’t seem to provide the same kind of feedback. As a result, when children spend too many hours inside, their eyes fail to grow correctly and the distance between the lens and retina becomes too long, causing far-away objects to look blurry.
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A restless nature was once helpful to people who needed to find food sources in the wild, but in today’s classrooms, it’s often classified as attention deficit hyperactivity disorder.
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if your child is going to stick his nose in a book this summer, get him to do it outdoors.