Experts reveal best ways to save an aging brainWant to keep your wits sharp as the years go by? You're not alone. Most people are worried about losing their memory as they age, and a new study shows it's a valid concern: In fact, at 53 percent -- more than half of all people -- have at least a minor mental decline in their 70s and 80s, and about 16 percent develop more serious problems with memory and other mental functions as they age.