How the Mind Ages

Mental function with age is largely determined by mental lifestyle, the impact of chronic disease and flexibility of the mind.

By Kristin White, published on November 01, 1993 - last reviewed on October 01, 2009

Kail likes analogies between mind and computer. "The comparison suggests that changes occur in several ways, and that a person's catalog of programs grows with experience. Instead of looking at mental development as simple growth, or a series of leaps, we see it more as debugging."

Each time we address a problem that resembles one we've done before--which we often do in our jobs--we ask whether the current strategy can be improved. We're constantly evaluating different approaches, discarding the less efficient. This is why experience is the best teacher and why practice makes perfect.

THUNK BY CHUNK

Specialized knowledge is a mental resource that only improves with time. Crystallized intelligence about one's occupation apparently does not decline at all until at least age 75, and if there is no disease or dementia, may remain even longer.

Special knowledge is often organized by a process called "chunking." If procedure A and procedure B are always done together, for example, the mind may merge them into a single command. When you apply yourself to a specific interest--say, cooking--you build increasingly elaborate knowledge structures that let you do more and do it better. This ability, which is tied to experience, is the essence of expertise.

When an accomplished baker thinks "angel food cake," for example, essential ideas that beginners often look up in a cookbook spring to the experienced mind in a cluster: egg whites at room temperature, no all-purpose flour, fresh cream of tartar. The information is in a "chunk" that's recalled all in one piece.

Vocabulary is one such specialized form of accrued knowledge. Research clearly shows that vocabulary improves with time. Retired professionals, especially teachers and journalists, consistently score higher on tests of vocabulary and general information than college students, who are supposed to be in their mental prime.

Whatever the cause, it's a truism that many people become dissatisfied with their mental performance as they get older. Someday they may be able to correct any deficiences by taking a pill. "We think many of the deficits that come with age can be modified," says Thomas Crook, M.D., a psychiatrist who is president of Memory Assessment Clinics Inc., a private company based in Bethesda, Md.

His enthusiam is bolstered by the finding that medical patients given a class of drugs to treat hypertension--so-called ACE inhibitors, such as Captopril--spontaneously and inexplicably reported improvements in intellectual abilities. Ever since then, pharmaceutical companies have been trying to concoct drugs to repair deficits in cognition, particularly memory.

Crook's company performs clinical trials of candidate drugs and tests cognition in people of all ages. One test measures ability to recognize individual faces among hundreds flashed one at a time on a screen. A face may appear once, followed by several others, and then appear again.

"In some individuals, test performance does not begin to deteriorate until the late 70s," says Crook. "People of all ages make mistakes, even when a photo is presented twice in succession. The problem lies in attending to the task, not in the memory."

Perhaps one day there will be a tablet for regaining full powers of memory, or an injection of norepinephrine for maintaining the ability to pay attention. In the meantime, we have only to rely on the natural self-improvement systems of the mind and the storage capacity of the brain.

We can to some degree outwit the effect of time on the mind by adapting our mental procedures around whatever declines occur. Most of us, sooner or later, will lose in efficiency. We will have trouble juggling several different tasks at the same time. We can do as well as ever on any single one of them by planning work on one thing at a time, with fewer interruptions. And we can perform tasks as well as when younger if we take off the pressure to do them in a limited amount of time.

Best of all, perhaps, we have a great new rationale for slogging away at crossword puzzles.

PHOTO: Microscopic enlargements and cross-sections of brain tissue depicting neurons (DAVID PHILLIPS/PHOTO RESEARCHERS)

PHOTO: axons (BIOPHOTO/PHOTO RESEARCHERS)

PHOTO: capillaries. (SPL/PHOTO RESEARCHERS)

HOW TO AGE-PROOF YOUR MIND

Keep your job. Don't retire. Ever.

Stay physically healthy.

Become an expert in something-anything.

Take up the piano. Take a course in something.

Learn to roll with the punches.

Do crossword puzzles.

Go out with friends or find new playmates.