Contrary to stereotypes of the doddering elderly, research shows that half of people older than age 70 stay mentally sharp.
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The normal aging process does bring changes to the brain, says Denise Park, a neuroscientist at the University of Texas at Dallas. There is some shrinkage in the frontal lobes and some damage to neurons and their connections. Cognitive processing slows down. Yet that slowdown is usually on the order of milliseconds and doesn’t always make a meaningful difference in daily life. And to compensate, older people activate more of the brain for tasks such as reading. “Older adults will often forge additional pathways” for particular activities, Park says. “Those pathways may not be as efficient as the pathways that younger adults use, but they nonetheless work.”
The cliché that age brings wisdom is also backed up by science. “Where older adults really shine is in their knowledge,” Park says. If you think of the brain as a computer, “there’s a lot more on the hard disk,” she says. Older adults can draw on their experience and often have much better solutions to problems than younger adults. “Frequently that can give them an edge that is unexpected,” Park says.