How Your Brain is Shaped by the Life you Live

August 6, 2006    BY Alexandra Starr

Your brain is shaped by the life you live. The right mental, physical, and spiritual practices protect your mind, so you can have the very richest life possible.

For years, there was a fundamental disconnect between the way we perceived the brain and our physical body. While we knew there would be inevitable deterioration in our physical prowess as we aged, there was also an understanding we could mitigate the worst effects by exercising and paying attention to our diet. Our brain, however, was placed in a different category. After 40, we were told, it embarked on a slow and steady decline, and there was little we could do to stave off the decay. Luckily, we now know that particular theory of our mental life span is fundamentally flawed: The brain can grow and renew itself throughout our lives.

For years, there was a fundamental disconnect between the way we perceived the brain and our physical body.

To be sure, as we age, there are some changes in our mental capacities, particularly in our short-term memories. And a portion of our mental trajectory is determined by genetics. But scientists have documented that our most important organ is fundamentally “plastic.” That is, it reconfigures itself in response to our behavior. And if we make a point of nourishing our mental, physical, and spiritual selves, we can make real strides in protecting our mind as we grow older.

Part of the reason there was so much skepticism for so long about our ability to mold the architecture of our brain was that we couldn’t witness the process, the way, say, we can see a muscle respond to weight lifting. But the introduction of magnetic resonance imaging (MRI) has opened the secrets of the mind, allowing us literally to peer into our head. And the verdict is that the brain reacts in very specific ways to the activities we undertake, much the way the body is honed by physical exercise.

A use-it-or-lose-it message is unmistakable. A study of London cab drivers, for example, found that their hippocampus—the region of the brain that is particularly involved in spatial memory—was significantly larger than in the general population. An investigation involving musicians showed that in their MRIs, the region of the brain most involved in processing music was enlarged. Consistent mental calisthenics, it turns out, leave a lasting imprint.

A similar dynamic emerged in studies of meditators. Calming the mind’s habit of moving restlessly from one experience to another prepares us to experience pure consciousness. It strengthens the spirit and the mind. Those who practice consistently build up the frontal cortex, the part of our mind involved in planning, coordinating, and tapping our memory. A study at Massachusetts General Hospital found that older meditators who had been engaged in the practice for nearly a decade had gray matter density in a portion of the frontal cortex that was comparable to that of subjects in their 20s. (The frontal cortex usually “thins” with age.)

While specifically engaging the mind is important, safeguarding our mental prowess goes beyond giving our neurons a workout. Physical health has a big impact on mental acuity: Even moderate doses of exercise can help fortify the brain. Our connection to the broader world is also important. People who are in regular contact with others seem better prepared to weather aging. Those relationships don’t have to be with just long-term friends or family members. Studies have shown that mentoring at-risk children, or engaging in group activities such as playing bridge or softball, can improve our cognitive well-being, too.

While specifically engaging the mind is important, safeguarding our mental prowess goes beyond giving our neurons a workout.

Perhaps it is not so surprising that to insure we have the best chance of leading rich, full lives in our later years we need to engage the mental, physical, and spiritual. As yogis have always known, these facets of our lives are inextricably connected. It’s not necessary to become a champion meditator, or a marathon runner, in order to boost our chances of a healthy old age. Even moderate changes, some of which can be squeezed into extremely busy schedules, can have an impact. “It’s about finding that right combination of effort and calmness,” explains Robert Svoboda, BAMS, a renowned ayurvedic specialist. “And understanding that if we make incremental changes, we’ll see a difference, perhaps not immediately, but over the long term.”

How Hobbies Made Einstein and Churchill Smarter

In order to understand how we can best care for our mind, it helps to have a rudimentary understanding of how the brain works. One of the most notable characteristics of our three-pound organ is its two hemispheres. Most of us have heard of the right brain and left brain dichotomy: To resort to stereotypes, the left brain is in charge of rational and analytical thinking, while the right side is more holistic and creative.

Scientists seem to agree that casting our two hemispheres as the accountant-versus-artist showdown is far too simplistic. There are various theories of what the actual division of labor might be, but one of the most provocative hypotheses has been put forward by New York University neuropsychologist Elkhonon Goldberg, PhD. He theorizes that the right hemisphere of the brain is better at tackling new tasks, while the left side of the brain is superior at executing familiar routines. So, for example, when you are learning to speak a new language or to play a musical instrument, the right side of the brain might do the heavy lifting early on; once you gain proficiency, the left side of your brain becomes more dominant.

As Goldberg explains in his book The Wisdom Paradox, he first began developing this hypothesis in the 1960s, when as a young student in Moscow he was intrigued to learn that children who suffered damage to the left hemisphere fared much better than adults who suffered similar trauma. When it came to injuries to the right side of the brain, the opposite was true: Adults were able to bounce back in a way the children could not.

If Goldberg’s theory is correct and the right side of the brain is best suited to deal with novel challenges, it would help explain that pattern. Kids, after all, are constantly acquiring new skills, whether it’s learning to crawl as an infant or performing algebra as a middle schooler. Adults, in contrast, generally draw on the competencies they developed when they were younger—whether it be reading or driving—to navigate the world. So children, constantly trafficking in the new, vigorously employ the right side of their brain, while adults exercise mostly the left side. And indeed, autopsies of aged brains generally show a much more robust left hemisphere.

Goldberg points out that two giants of the 20th century—Albert Einstein and Winston Churchill—engaged in hobbies that fell far outside of their day jobs of theoretical physics and high-powered politics. (Einstein played the violin, while Churchill was an accomplished amateur painter.) The NYU professor postulates that both men intuitively grasped that exercising different mental muscles would boost their overall capabilities. Goldberg decided to write for the general public in part to stretch himself in new ways. “I wanted to escape a life on autopilot,” he says. “If you don’t want to be at the mercy of the ravages of old age, you need to seek out mental challenges.”

Both men intuitively grasped that exercising different mental muscles would boost their overall capabilities.

Those challenges, of course, don’t need to fall into the category of producing tomes on brain science. Studies have shown that learning a new language late in life or mastering a musical instrument can build up our brain’s gray matter. Dahlia Nagel, a Berkeley, California, resident who took up German in her early 50s doesn’t play down how grueling it is to learn a new language: Her first introductory summer course had her studying German nouns and verbs almost 10 hours a day. Now advanced enough to read German literature in the original, she describes the payoff in exuberant terms. “It’s been an eye-opener both for the mind and spirit,” she says. “It’s tremendously rewarding to be able to pick up a Franz Kafka novel and fall into the depth and beauty of it.”

Surprise Your Brain with Something New

To be sure, some adult lives simply do not afford the time to learn violin or Deutsch. But most of us can make the time for a crossword puzzle, the occasional board game, and reading books and newspapers. Not only are those activities enjoyable, a seminal 2003 study established they were associated with lower risk of cognitive decline. And how many of them you do makes a difference: Researchers found that the risk of dementia was reduced by about 12 percent for each challenging hobby a person took on. How often you work the activities into your schedule has an impact, also: For example, older adults who did crossword puzzles four days a week had a risk of dementia that was 47 percent lower than those who did them just once a week.

Even small adjustments in our day-to-day routine can have an effect. “You want to make sure that you’re not just relying on existing patterns,” says Michael Patterson, project manager for the Staying Sharp Initiative, a joint program of NRTA (AARP’s educator community) and the Dana Alliance for Brain Initiatives. Breaking out of our daily grooves is easier—and more fun—than might first be apparent. For ideas, Patterson recommends the book Keep Your Brain Alive, co-authored by the late Lawrence Katz, who was a neurobiologist at Duke University. Katz advised presenting the brain with unexpected experiences in the course of our daily lives. Some of his suggestions: brushing your teeth with your non-dominant hand and eating with your eyes closed (preferably in the privacy of your home). Those small changes—which Katz called “neurobics”—create more connections among our brain areas, and make our mind more resistant to the effects of aging.

Given the demonstrated benefits of mental workouts, it might not be so fantastical that eventually we’ll see so-called cognition facilities where people could be given training sessions specifically tailored for their brain. As Goldberg points out, half a century ago the concept of gyms and health clubs that catered beyond a small elite was almost unfathomable. Now you can’t pass a city block without running into one.

Tango, Anyone?

Of course, you could argue that in one sense the gym is already a sort of cognition center, given how exercise demonstrably strengthens our mind. That’s true even for the modest amounts of physical movement. A study released earlier this year found that just walking for 15 minutes three times a week had a positive effect on older persons’ cognitive function. Once again, the amount of time you invest makes a difference: People who exercised three or more times a week had a 30 to 40 percent lower risk of developing dementia compared with those who exercised fewer than three times per week. While walking will do the trick, engaging in activities that require us to actively concentrate imparts greater benefits. A study conducted at McGill University in Canada found that older adults who devoted two hours a week to mastering the tango versus just walking showed more improvements in their balance, motor coordination, and mental acuity than the walking group.

While walking will do the trick, engaging in activities that require us to actively concentrate imparts greater benefits.

Why does physical activity protect our brain? One theory is that it boosts blood flow to the areas of the brain used for memory. The release of endorphins—those hormones that reduce the sensation of pain—probably doesn’t hurt either. Plus exercise can help keep our weight down and cholesterol levels low, which reduces our chances of developing heart disease or diabetes or suffering from a stroke—all medical conditions linked to the development of Alzheimer’s disease.

Mental Muscle for Meditation (and Vice Versa)

While the importance of exercise has become something of a shibboleth in American society over the past few decades, the benefits of meditation are only now beginning to gain broader attention. The practice of quieting and focusing the mind has, of course, been a mainstay of the yoga tradition since Vedic times (3000 bc). Scientists have documented that Buddhist monks—basically the Olympic gold medalists of meditation—have different brain structures from ordinary people. A study at the University of Pennsylvania found that when they are engaged in meditation practice, Tibetan Buddhist monks increase the activity in the area of the brain in charge of concentration and simultaneously decrease the activity in the part of the brain that oversees spatial awareness. The brain imaging reflected what the monks described: They lost all sense of space when they achieved a transcendental high. And indeed, when the mind is completely centered for an extended period of time, the practitioner can be put in touch with a part of herself that is beyond the constraints of time and space, and becomes more aware of the inner workings of the Self.

The benefits aren’t limited to the arch-professionals. Sara Lazar, an assistant in psychology at Massachusetts General Hospital, found that people who meditated just 40 minutes a day had thicker gray matter in their frontal cortex, too. Lazar’s study also lent credence to the idea that the brain responds in very demonstrable ways to how we employ it. For example, preliminary data suggest that in the meditators who also practice asana, or yoga postures, the region of the brain that is in charge of hand movement was thicker.

The concept that meditation shapes our mind in beneficial ways is not surprising to Pandit Rajmani Tigunait, spiritual head of the Himalayan Institute. “It brings a qualitative change in how you perceive yourself, other people, and life,” he says. While he meditates several hours a day, he stresses that even a daily 15-minute meditation practice can make a difference. “I’ve seen people at all levels get enormous results.”

Robin Goldman, PhD, who conducts brain research at Columbia University, can vouch for the benefits for a self-described “newbie” practitioner. After attending a seven-day silent retreat at the Insight Meditation Society’s center in Barre, Massachusetts, she began meditating for half an hour a day on average. The practice session itself is not easy for her. “It’s a difficult thing to do, to sit, and quiet down your brain, and concentrate on your breath,” she says. “But when you try to do that, you develop not just patience, but also compassion for yourself and other people.” The aftereffects, she says, stay with her throughout the day. Cultivating mindfulness in solitude has made it easier for her to enjoy the company of other people.

Generosity and the Functional Septuagenarian

Both sides of Goldman’s experience—the individual mental conditioning and the more positive interactions she has with a broader community—are important to protecting the mind. Growing older can be isolating: Friends and family members die, and after retirement, people oftentimes miss daily interaction with colleagues. Those who nonetheless retain social connections are often better prepared to enter the final decades of their lives, according to the seminal MacArthur Study of Successful Aging, which followed nearly 1,200 highly functional septuagenarians for seven years. Marilyn Albert, PhD, a professor of neurology at the Johns Hopkins School of Medicine, speculates that a key component of a healthy older life is feeling as though you continue to play a role in the world. She points to a study conducted by colleagues at Hopkins, which showed that seniors who volunteered with inner-city children built up their brain architecture. “It seems like these people had an increased sense of self-efficacy, which perhaps made them feel they had a greater sense of control over their lives,” says Albert. In helping young students make the transition into adulthood, it turns out that these people improved their own prospects for healthier chapters in their old age.

Albert travels around the country lecturing on protecting the brain, and during question-and-answer sessions people frequently ask what hobbies and exercises they should incorporate into their schedules. Her response: “There is no one way. Find what you like to do.” Indeed, from meditation to crossword puzzles, the number of activities that can help us keep our cognitive facilities sharp seem almost innumerable. In this diversity of options, there is one constant: The benefits we reap hinge on our level of commitment. In study after study, the length of time people had engaged in an activity, and the amount of time they devoted to it, strongly affected the imprint it left on the brain.

Her response: “There is no one way. Find what you like to do.”

The shaping of our brain by our behavior offers us an extraordinary opportunity: While we cannot choose our genetic makeup, we can decide how we invest our time and energy. Maximizing our opportunities for a full life requires effort, discipline, and generosity. But the payoff more than equals the investment: In protecting the organ that largely determines how we negotiate and relate to the world, we can help assure that every stage of our lives is as rewarding as it can possibly be.

Alexandra Starr
Alexandra Starr, a 2007 Milena Jesenská journalism fellow, writes on immigration and social issues.

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