A to Z Health Guide 2007

The ability to see depends on more than just healthy eyes sending signals to a working brain. The brain must also learn how to interpret the incoming information. Neurologists have long been convinced that there is a critical period — before age 6 — during which this must happen or else the brain's visual abilities will never be configured. A child who is born blind but whose sight can be restored by surgery thus has a limited time to undergo an operation. But this window is bigger than previously thought. Scientists from MIT published a paper in Psychological Science about a 32-year-old woman in India whose cataracts were removed at age 12. Investigators who recently caught up with her found that while her vision will never be 20/20, she does see reasonably well, giving new hope to many blind kids.