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The brain ages just like the rest of a body, says a new report that urges seniors to take steps to keep sharp.

The prestigious Institute of Medicine examined what scientists know about "," changes in mental functioning as we get older.

This isn't a disease like Alzheimer's but a natural process—and it's not always bad. Wisdom can indeed increase with age, and years of experience can prove invaluable, stressed Dr. Dan Blazer, an emeritus professor of psychiatry at Duke University who chaired the IOM committee.

"The brain ages in all of us. But there's wide variability in the way the brain ages," Blazer said.

Staying cognitively sharp is one of the biggest concerns of seniors, with good reason. Tuesday's report warns that even subtle slowdowns can affect daily life, making seniors more vulnerable to financial scams, driving problems or other difficulties in a technology-driven world.

Indeed, while some people will experience little if any cognitive change, many process information more slowly, and have more difficulty multitasking than when they were younger, the report found. What's called working memory—the brain's short-term storage—often declines with age but typically long-term memory remains intact even if it takes longer to recall someone's name.

That kind of change may not be obvious until, say, someone is faced with a complex financial decision or forced to make a transaction quickly and has trouble, Blazer said. Older adults are losing nearly $3 billion a year, directly and indirectly, to financial fraud, the report noted.

What's the difference between normal aging and cognitive decline?

"There's no clear line that we can draw here," Blazer cautioned.

Someone experiencing memory difficulty needs to be checked by a doctor, said IOM panelist Dr. Jason Karlawish of the University of Pennsylvania. With Alzheimer's, nerve cells in the brain die. With normal cognitive aging, neurons don't die—they just don't work as well, he explained.

The best advice for staying sharp as you get older: Be physically active. The sooner you start the better, but it's never too late, Blazer said.

The IOM also recommended:

—Control high blood pressure and diabetes, and don't smoke. Those are key risks for heart disease, and what's bad for your heart is bad for your brain.

—Some medications commonly taken by seniors—including certain anxiety or sleep drugs, antihistamines, bladder drugs and older antidepressants—can fog the brain, so ask about yours.

—Keep socially and intellectually active.

—Get enough sleep.

—Be careful of products that claim to improve cognitive functioning. There's no evidence that vitamins and dietary supplements like ginkgo biloba help, Blazer said. And the jury's still out on whether computer-based brain-training games do any good, he said.

The IOM also urged more research into normal cognitive aging, which has been left somewhat behind the study of diseases like Alzheimer's, and more education of doctors about their patients' risks. For example, hospitalized seniors are at increased risk for delirium—sudden confusion and agitation—that can cause lingering after they go home, but there are ways to prevent it.

The IOM also said government agencies and communities should consider cognitive aging as they set policies and programs. It cited a California law to protect older adults who are signing up for reverse mortgages, and a Michigan plan to improve older driver safety through such steps as adjusting traffic lights to counter glare.