Most people believe that as we get older, our brains will inevitably lose our precious little nerve cells. Losing those nerve cells, or neurons, means that we'll also lose our ability to think, right? Well, as it turns out, you can lose a pretty substantial number of neurons without suffering mental decline. We do lose neurons every day, but the more we put our remaining ones on overdrive, the more we'll be able to maintain our mental acuity.
You certainly must know people either your age or much older who can outsmart almost everyone younger than them on everything from Words with Friends to remembering the phone numbers of all their friends and acquaintances. Maybe you're even one of those lucky folks yourself. Plenty of celebrities, politicians, scientists, actors, artists, comedians and literary types also seem to have the edge on their younger peers. It turns out that these "Age Busters," as I've called them elsewhere, share the ability to use their brains to their best advantage. It might be genetics, it might be luck, but my guess is that their success in staying mentally sharp rests on their commitment to keeping as active as they can.
We don't need to rely on guesswork, however, to find out the secrets to a long and mentally active life. Researchers are well on their way to discovering the elements of what they call successful cognitive aging," in that they stay above the norm on tasks that require memory, planning and general knowledge. They take advantage of what neuroscientists call brain or cognitive "plasticity."
Northwestern University's Theresa Harrison and colleagues identified a subset of people in a 2012 study whose brains were particularly plastic. When given memory tests, they performed at the level of the average middle-aged person. Their superior memories earned them the label "SuperAgers." When Harrison and her team looked at the brain scans of the SuperAgers, they found that they were equivalent in key areas to those of the middle-aged participants, and better than those of the age-matched non-SuperAger peers. Their brains did not show the tell-tale wear and tear that otherwise occur in normal aging.
Other research looking more broadly at the brain scans of hundreds of midlife and older adults confirm the idea that your brain can remain vital and healthy throughout life, and if it does, so will your mental prowess. UC San Diego researcher Jeste teamed up with a group led by Lisa Eyler in 2011 to review 80 of the best of these studies to discover the common elements in successful brain aging. As it turned out, there were some hints that "bigger is better" when it comes to the brain, but size is not as important as what people do with the brains they have. Scaffolding theory says that people can build upon their existing brain structures to put them to optimal use. If one part of your brain region is weak, another part can pull a swap and work on its behalf. These strategies have names. In Hemispheric Asymmetry Reduction in OLDer adults (HAROLD), a region in one hemisphere takes up the job usually carried out by the corresponding region in the other. In the Posterior-Anterior Shift with Aging (PASA), the front part of the brain does the extra work when the structures toward the back lose their effectiveness.
If you want to be a SuperAger, the moral of the story is clear: Take advantage of the principles of plasticity by consciously putting your brain's structures to work. Feel that your memory is slipping? Don't give up. Whether you use high-tech or low-tech devices to keep information handy, try going without your contact list, notebook or even calendar. Little by little, stretch your memory more until you can confidently go through your day without relying on all those mental crutches. Set aside your calculator and go back to that long division you learned in school when you're trying to figure out the unit price of cereal on the grocery store shelf. While you're at it, buy a book of simple games (Sudoko, crosswords, number puzzles) and practice, practice, practice, until the games become easy. Because successful cognitive aging means you might pull a left brain-right brain switcharoo (HAROLD), you can draw on your right brain's ability to pick up some of the slack that those language centers in the left brain are finding to be a challenge.
Exercising mentally and physically can benefit your brain as well as your overall health. Neurons need oxygen and glucose to survive. By sending nutrients their way, you'll increase their functional life spans. However, that mental activity does more than provide nutrients, it also helps your neurons build their connections to other neurons. These connections, or synapses, grow and grow in response to the stimulation you provide them. There's a lot to be said for the "use it or lose it" mantra, and it's true no more so than in the brain. Not everyone can be a SuperAger, but by trying, you'll make your chances that much more likely for becoming a successful brain ager.
For more details on the studies mentioned here, check out my Psychology Today blog posting: Successful Brain Aging: Is Bigger Always Better?