August 2, 2009
The Chronicle Herald
Silver Donald Cameron

‘DONALD,” said Aunt Ethel, “do you know a book called The Brain That Changes Itself? It’s by a Dr. Norman Doidge. It’s absolutely fascinating, the new things they’re learning about the brain. I’d love to discuss it with you.”

The Faithful Reader knows that Aunt Ethel, now 97, is the person I want to be when I grow up. When she recommends a book, I buy it. And the book really is fascinating — not least because it casts some light on how to grow up like Aunt Ethel.

For generations, neuro-scientists conceived the brain as a sophisticated but inflexible machine. Specific areas of the brain were responsible for specific mental and physical functions, and when parts of the brain were damaged or destroyed, those functions were irretrievably lost. The wiring connecting the brain to the mind and body was fixed and unchangeable.

Recent research, however, reveals that the brain is “plastic,” adaptable, capable of making spectacular changes when necessary. Stone-deaf people can hear through a microphone linked to an electronic wafer placed on their tongues. The blind can see when skin on their backs is stimulated by tiny electric currents generated by a camera. It seems that the areas of the brain responsible for sight and hearing can respond to stimuli from completely novel sources. And that’s only the beginning.

The new picture of the brain opens vast new opportunities. Take old age, for instance. We have long known of a “critical period” in infancy when youngsters learn furiously — learn to balance, to walk, to talk (sometimes in several languages) and much more. The infant’s brain is “plastic,” shifting and growing and constantly reshaping itself.

Thereafter, alas, the brain seems to freeze and then go into reverse. Learning a new language as an adult is fiercely difficult. As we age we often lose our sense of balance and our memory along with our teeth and our hair. We become cautious, rigid and cranky. People over 60 today can expect to live well into their 80s — but, says Dr. Michael Merzenich, one of the leading scientists in Doidge’s book, “when you are 85, there is a 47 per cent chance that you will have Alzheimer’s disease.” Who wants to stick around for that?

One of the most important insights from Merzenich and others is “use it or lose it” — keep learning, or lose the ability to learn. By the time we reach 60, most of us haven’t learned anything really new for decades. We’re using “mastered” skills, and our capacity to learn is like a neglected muscle.

Starting with lab experiments, and moving on to examine such bewildering phenomena as autism, Merzenich and his colleagues developed an exercise program for basic brain functions in language-impaired and learning-disabled children. The program worked so well that the scientists began to wonder whether similar exercises might stave off some of the effects of aging. The results of their experiments suggest that elderly people who really start exercising their brains — getting outside their comfort zones by learning a new language, learning new physical activities that require concentration, taking up a new career — actually can re-invigorate the brain’s plasticity.

Merzenich’s experiments with rats also suggest that the plasticity of the infant mind may be recaptured by artificially “turning on” the nucleus basalis, the part of our brains that allows us to focus our attention. In the future, that might allow us to learn languages, job skills, or academic disciplines as easily in adulthood as we did in youth.

In the meantime, says Merzenich, anything that requires intense focused attention will reduce the mental losses of aging. Study Mandarin, learn to rhumba, write your memoirs, create computer code. Learning really is living, Doidge argues. “We must be learning if we are to feel fully alive.”

And suddenly I heard the voice of Aunt Ethel.

“If, as I believe, we are put on this Earth to learn,” she once told me, “then I am not leaving until I have learned every single lesson that’s available to me.” And perhaps that’s the secret of a life so long and rich that at 97 you are not lost in the mazes of your memory, but eagerly reviewing the latest advances in brain science.