Aging comes with many trials and tribulations, including the decline of the senses: sight, hearing and even smell, taste and touch.
Fortunately, exercising the brain strengthens these senses -- just like exercising the muscles strengthens the rest of the body.
"The brain is a very healthy and resilient organ. That's one reason why we really need to be upbeat and positive about taking care of it," said Patricia S. Daniels, a National Geographic contributing author who explored how brain health influences the senses for the publication's Mind Body Wonder series.
Physical exercise -- like walking, swimming and tai chi -- stimulates our most important organ. Playing games, taking classes and other mental exercises can ward off cognitive decline too.
"Particularly if you're learning a new skill," Daniels said. "Not something you've done a million times -- something that takes a little bit of work to master. These things really build your neural connections."
Even social contact has a surprisingly strong effect.
"That's a reason not to be isolated and not to be sitting at home in the corner with the screen," Daniels said. "You really need to get a variety of stimulations during the day. Use your eyes, use your ears."
MORE: Small bursts of exercise daily may lower risk of death by 40%, study shows
Daniels emphasized that it's never too late for your brain -- it will build those new nerve connections until the day you die.
"If you've done nothing but sat in a chair in the corner of your whole life, you can still pick up and get moving," she said.
And stay optimistic.
"They actually find that optimistic people live longer than pessimistic people, so you should keep your hopes up always," Daniels said.
Some mental skills, like vocabulary, actually sharpen with age. Learn more at NatGeo.com/health.
ABC OTV and National Geographic will explore health and wellness through four lenses: longevity, women's health, brain health, and diet and nutrition. Using the latest in scientific research and information from experts in the medical field, we'll answer questions about what's essential to the future of your health.
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