New Book says Cross-Train Your Brain to Increase Mental Function
DURHAM, N.C. - Shower with your eyes closed. Take a different route to work. Learn the braille numbers in the elevator for the floors. Hold your nose as you try different foods to explore how the taste changes.
These are among 83 "neurobic" exercises advocated by Duke Medical Center neurobiologist Lawrence Katz and co-author Manning Rubin in their new book Keep Your Brain Alive (1999, Workman Publishing Co., New York).
In the book, Katz, a Howard Hughes Medical Institute Investigator at Duke Medical Center, takes out of the laboratory and into everyday life the latest insights into how the brain can rewire itself to adjust to new experience. And, indeed, new scientific evidence shows that the brain can rewire itself, even in adults, Katz said in an interview.
"It was not appreciated for a long time how, even quite late in life, the brain has quite a lot of residual capacity for reorganization."
Basically, brain cells learn by making new connections with one another, growing tendril-like connections called dendrites, said Katz and Rubin, senior creative supervisor at K2 Design in New York City and the author of 60 Ways to Relieve Stress in 60 Seconds. These dendrites connect with neighboring cells through linkages called synapses. As brains age, these dendritic connections may thin out, but Katz and Rubin advocate mental exercise as a way to enrich those connections.
"It's long been clear that during critical periods early in life, people's brains set up some of their very basic circuits," he said. "But the long-held idea that after that, brain connections were frozen is probably not true. And, in fact, it's obvious that people learn things throughout our lives; even if they're 80 years old they can learn new things."
Katz emphasizes that "neurobics" is not about doing puzzles or brain-teasers, but about using the full range of the senses to help forge new connections among the different sensory structures of the brain.
"A huge area of our brain is devoted to processing sensory inputs, because that's how we deal with the outside world," he said. "And the senses need to know what's going on in the other senses as well, to try to make predictions about the future. So, for example if you hear a gunshot and see a bottle next to you explode, you make a very strong association that, that sound means something bad." When we "starve" our senses, brain function degrades, Katz said.
"We believe that people use the same senses in modern life over and over again, so that they end up using lots of visual and auditory associations. But by bringing the other possible associated sensory pathways on line, you actually increase the repertoire of brain pathways that are activated." Unfortunately, said Katz, the conveniences of modern life have robbed us of some of this sensory richness.
"We don't forage for food in the dark, for example, where we have to rely on smell to know whether we're near a rotting log, or touch to feel our way along. We just don't rely on such richness of sensory input very often, so those kinds of possible conjunctions are underused."
Thus, in their book, Katz and Rubin recommend 83 different exercises that use not only the five usual senses - vision, taste, smell, touch and hearing - but also what they call the "sixth sense" of emotion.
The authors' criteria for such neurobic exercises are that they:
Involve one or more of your senses in a novel way.
Engage your attention.
Break a routine activity in an unexpected, nontrivial way.
With these criteria, the book divides its list of 83 neurobic exercises into six categories of daily routine:
Starting and Ending the Day. Suggested example: go through your morning hair-combing, tooth-brushing routine using the nondominant hand.
Commuting. Close your eyes as you get into the car, find the keys and start the car.
At work. Make a "sensory canister" containing such aromatic substances as sage, thyme or cloves and take a whiff when you dial a certain phone number. See if it helps you remember the number.
At the market. Go to new markets such as an ethnic market or a bakery to experience new sights and aromas.
At mealtimes. Share a meal in silence and see how it affects your sensory experience of the food.
At leisure. Go camping or visit a place you've never been.
The aim of neurobics is not to increase intelligence, Katz emphasized.
"Neurobics is not going to make you have the brain of a 20 year old. And it's not going to make you smarter than you were. It's the equivalent of a physical exercise, in that it's designed to keep you mentally fit and able to engage in a wide range of mental activities. It's designed to preserve and firm up your mental capacities not to augment them.
"It may open up new avenues for your thought processes. It may give you a richer net of connectivity within your brain, so that you have more possible avenues for solving problems and thinking creatively, and even just remembering things," he said.
"It may also allay some of your fears about aging because you're doing something about it; you're doing something that actively engages your brain."
As evidence that such neurobic "cross-training" can be a powerful, natural mental stimulant, Katz cites the compelling memories evoked by mere smells.
"A good example is the association of the smell of roses with romance. We may not remember when we made that association, but it just happened at some time, and it stays with us.
"Or when you learn to associate the smell of leaves with autumn, which brings back all these unconscious associations with the feel and colors of dry leaves, of apple-picking, of going back to school. It just comes back like that. And you've made all these associations by just living. Just experiencing life fully is good for the brain, Katz said.
"For example, if you go on a trip to Europe, don't spend your time sitting on a tour bus, sleeping in an American-style hotel and eating at McDonald's. Instead, rent a car, figure out the roads and drive to a small town where you don't speak the language, and stay in a local bed-and-breakfast and try weird foods."