The Secret Life of the Grown-up Brain: The Surprising Talents of the Middle-Aged Mind - Barbara Strauch (2010)

Part I. The Powers That Be

Chapter 4. Experience. Judgment. Wisdom

Do We Really Know What We’re Talking About?

There’s an argument to be made that the true test of a human brain is its ability to figure out other human brains.

Not long ago, when I mentioned that I was writing a book about the middle-aged brain to a friend, her first question was about the younger, trainee brains she had at home. As a mother of three girls, all in adolescence, she wanted to know, in a wishful way, only one thing: Does judgment improve? Do we get better at dealing with other humans, at making the right call?

Yes—and such insight is rooted in brain biology. We can now detect—even watch—mature judgment grow in our brains. The connections that help us identify the bad guys or the wrong road get stronger, and they may be at their strongest at middle age.

Thomas Hess, a psychologist at North Carolina State University, has done dozens of studies of what he calls “social expertise,” which he finds peaks in midlife, when we are far better than those younger andolder at judging the true character of others. Such tricky evaluations get easier—and closer to the mark—as we age. And it’s the nature of how our brains develop that gives us that advantage.

By middle age, we not only have more years of experience with real people in the real world but the brain cells devoted to navigating the human landscape turn out to be exceptionally durable. Scanning studies show that parts of the frontal cortex that deal more with emotional regulation atrophy less quickly than other brain sections as we age. And it’s that mix of emotional control, mental prowess, and life experience that helps us make the right calls.

“Some areas of the brain that appear to be involved in processing of socioemotional information . . . exhibit relatively less neuronal loss than other parts of the brain,” Hess told me. “As individuals progress through life, they interact with others and acquire culturally based knowledge [about] . . . why people behave the ways that they do.

“The fact that middle-aged adults appear to be the most expert is consistent with notions that midlife is a time of optimal functioning,” he added. “Basic cognitive abilities are still relatively high, and there’s also a fair amount of experience . . . [so they] function at high levels in everyday settings.”

And those everyday settings include a wide range of activities. David Laibson, at Harvard University, for example, has done fascinating studies in the emerging field of “neuroeconomics”—how people use their brains to make financial decisions—and he, too, finds we’re most adept at this in middle age. Laibson has found that when confronting complex money issues, such as mortgages or interest rates, those in middle age make the best choices. In studies around the world, Laibson has found that people roughly between the ages of forty and sixty-five more easily grasp the consequences of financial decisions and have better judgment overall.

In fact, Laibson goes so far as to pinpoint the apex of all this: His research finds that those who use the best judgment in matters of personal economics are in their fifties.

“That seems to be the sweet spot in terms of all this,” Laibson told me.

Weighing Wisdom

So what is this sweet spot? Is it judgment? Is it social expertise? Is this what we call wisdom?

The concept of wisdom—perhaps the most clichéd cliché of aging—has deep roots. It’s mentioned frequently throughout literature, notably in the Bible, where it’s described as a special mix of heart and mind. Most neuroscientists regard the concept with suspicion. Even now, those who will speak out loud about the idea divide into camps, albeit overlapping ones. Some assign wisdom’s weight to emotional equilibrium, beginning with William James’s famous declaration in 1890 that wisdom is “the art of knowing what to overlook.”

Perhaps not surprisingly, there aren’t many scientific studies that focus on the ability in middle age to keep one’s eyes closed or mouth shut. But the James notion does have an uncanny similarity to work by Laura Carstensen and Mara Mather showing that emotional regulation increases with age.

As we get older, we also have more mixed emotions, a trait that works in our favor. A study by Susan Turk Charles found that when viewing a scene of clear injustice—a film clip from the movie The Great Santini, for instance, in which an African-American man with a lisp is mocked by a white man, or a clip from the movie The Curse of the Working Class, where a husband yells at and hits his wife—younger people react only with anger, but older people are both angry and sad.

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This more complex, nuanced response to the world slows us down, restricting impulsive acts. And that may be good for our own survival, as well as that of the group—another case in which a middle-aged brain may function better simply because of how it’s set up. “If you have one emotion it is easier to act,” Charles explained. “And if you’re on the savanna and a lion is chasing you, that quick action may help you get out of there. But in our complex world, it might be good to go slower, to think twice.”

Even among scientists, the search for wisdom has a rich history and one not reserved to pure biology. One of the most prominent of the early life-span researchers, Paul Baltes, was, before he died several years ago, head of the highly respected Max Planck Institute for Human Development in Berlin. Baltes became fascinated with the possibility of scientifically deconstructing the building blocks of wisdom and spent years on what became known as the Berlin Wisdom Project. That project searched for wisdom anywhere it could, including the study of proverbs such as the Serenity Prayer (“God, grant me the serenity to accept the things I cannot change; courage to change the things I can; and wisdom to know the difference”).

In the end, Baltes and his colleagues settled on a series of hypothetical questions about life choices, the right answers to which, they believed, equaled wisdom. The answers rested largely on the ability to consider variables—to look at the big, messy picture. For example, one question might be: What’s the best way to get to Chicago?

Responding off the tops of their heads, some might answer quickly, saying something like, “Get on a plane.”

But a few would take the time to consider the variables—the messy picture—and ask more questions to narrow the possibilities: “Well, tell me, how many people are going? How much time do you have to get there? How much do you want to spend? How long will you stay?”

And while such hypothetical questions might seem simplistic, they nevertheless illustrate the complex ways our brains operate day in and day out. Considering the various ramifications of a situation, Baltes believed, means you have a brain that takes the measured, long—and wise—view.

After many years of such testing, Baltes and colleagues, while allowing that it’s possible to be wise and young, decided that those who scored the highest on this sort of question and were, therefore, in their terms, the wisest were around sixty-five years old—and that peak was reached after a fairly long trek along the middle-aged “plateau” of sustained wisdom-ness.

Following in Baltes’s footsteps more recently, Monika Ardelt, a sociology professor at the University of Florida in Gainesville, has put together an intriguing scale that determines how wise a person is by his ability to cope in the actual world. She measures a person’s wisdom according to how well he performs in three dimensions: cognitive, which she describes as the “desire to know the truth and be able to look at gray and not see everything in black and white,” as well as the ability to “make important decisions despite life’s unpredictability”; refl ective, the ability and willingness to look at different perspectives; and affective, the level of sympathy and compassion for others.

Ardelt has now matched outcomes on her measures against a set of data from Harvard University, which has been tracking a group of 150 men for more than forty years. Although she is still refining her findings, Ardelt told me that she’s found distinct correlations between high scores on two different three-dimensional wisdom measures at midlife and in old age, and certain personality traits found in the Harvard study.

In an in-depth study of eight long-term participants, the most decisive factor that predicted wisdom was their level of self-centeredness. By her measure and Harvard’s, it was those who focused on something outside themselves who turned out to be the most wise, a message, of course, that we’ve been told—and often ignored—for centuries.

“It was really striking,” Ardelt told me. “Those who were high-high (wise at both fifty and eighty) also scored very low on self-centeredness. They cared about others. They were giving in some way or another. And those who were primarily concerned about themselves, or their standing in the community, scored very low on the wisdom scale.”

Ardelt believes such wisdom comes directly from taking a broader perspective over time. Clearly, as she says, there are still “a lot of old fools” out there. Wisdom does not always develop automatically. And, as she puts it, we live in a society that, rather than rewarding those who are selfless—who teach or care for others—instead glorifies those who think mostly of their own gain—those who seek money for money’s sake, for instance.

“We could have a society that fosters wisdom more,” she said, a bit ruefully.

For the most part, die-hard neuroscientists have regarded this kind of discussion as squishy nonsense. But that’s changing rapidly. Some are finding what they now call wisdom deep in the brain’s very structure and workings—and in the midst of middle age.

In particular, many equate wisdom with an increased capacity, as we age, to recognize patterns and anticipate situations, to predict a likely future, and to act appropriately. As Neil Charness, who studies expertise, puts it, human brains are “pattern recognizers par excellence.

“Humans are not called homo sapiens sapiens—knowing man—for nothing,” Charness says. “We can size up what is going on and figure out what course of action is most promising and we use hundreds of millions of patterns to guide the process.”

John Gabrieli, the neuroscientist at MIT, says it helps to understand this signature talent by thinking of something as simple as an apple. Even if the apple is only an outline on paper, or painted purple, or has big bites taken out of it, we still recognize it as an apple because that’s how our brains are set up. It might not look like a standard apple, but our brains, through years of building up connections, become quite good at recognizing even vaguely similar patterns and drawing appropriate conclusions. Studies have found that we handle situations better when we know something about the situation beforehand, when we recognize at least part of a pattern we’ve seen before, which is more likely to occur for a middle-aged brain than for a younger one. “It’s stunning how well a brain can recognize patterns,” Gabrieli says. “And particularly at middle age, we have small declines, but we have huge gains” in this ability to see connections.

In our own worlds, while we may take this for granted, we often have a sense that we can see patterns and grasp underlying concepts with greater ease. Elkhonon Goldberg, a professor of neurology at New York University School of Medicine, calls these established brain patterns “cognitive templates” and believes they’re behind an older brain’s ability to better predict and navigate life. Not long ago, Goldberg—at the “ripe middle age” of fifty-seven—decided to take stock of his own brain and the results were fairly good. Indeed, as he writes in The Wisdom Paradox, he began to realize that while he might have a harder time at strenuous mental workouts, he was also increasingly capable of a kind of “mental magic.”

“Something rather intriguing is happening in my mind that did not happen in the past,” he writes. “Frequently, when I am faced with what would appear from the outside to be a challenging problem, the grinding mental computation is somehow circumvented, rendered, as if by magic, unnecessary. The solution comes effortlessly, seamlessly, seemingly by itself. . . . I seem to have gained in my capacity for instantaneous, almost unfairly easy insight. . . . Is it perchance that coveted attribute . . . wisdom?”

If an older brain is confronted with new information, it might take longer for it to assimilate it and use it well. But faced with information that in some way—even a very small way—relates to what’s already known, the middle-aged brain works quicker and smarter, discerning patterns and jumping to the logical endpoint.

A friend of mine who has been a doctor for more than thirty years said she can now often instantly evaluate a situation, making it easier to come up with effective solutions. “When I walk into a hospital room now, there’s a lot in my head already,” she said. “I can still be surprised. But in a lot of cases I can foresee what will happen and that helps a lot to figure out what to do, what will work best.”

The Gist of It All

In many ways, of course, all this sounds a lot like what we like to call intuition or gut instinct. Neuroscientists don’t like to use such words. They prefer the word gist.

Defined broadly, gist is the ability to understand—and remember—underlying major themes. Here again, we get better at grasping the big picture—because of the intrinsic nature of how our brains operate.

A series of intriguing studies has shown that we more easily wrap our brains around a main idea and remember it better, too, as we age. If you give a child a list of fruits—apple, pear, banana, grape, for instance—he will be quite good at reciting the list verbatim. But beginning sometime in our teen years—probably due to the natural pruning of little-used brain connections and a corresponding fine-tuning of our brains—we focus less on individual units and instead look at groupings. By middle age, we easily recognize broad categories.

“Verbatim memory begins to decline after young adulthood but ‘gist memory’ remains intact and gets better even into older old age,” says Valerie Reyna, a neuroscientist at Cornell University who has done some of the most extensive studies in this area.

Another recent study along these lines found that as doctors gained more experience and became more accurate in making medical decisions about heart disease, for example, they made decisions, much like my friend the doctor, based less on a labored process of assembling remembered facts and more on gist—gut instinct—a shift that made reaching a conclusion both simpler and speedier.

“If you know a great deal about a topic, you can infer rather than remember,” Reyna told me. “But, in addition, the nature of your reasoning, judgment, and decisions changes. You use gist to get to the bottom line more effectively, reducing the need to rely on memory for details.”

In a way, it makes evolutionary sense for the brain to be set up this way. Confronted with vast savannas of stimuli, those who quickly brought all the stimuli together—odor, noise, movement—to understand the big picture would certainly have a better chance of surviving than those concentrating on tiny changes in the color of the leaves underfoot. Even in today’s world, this talent proves handy. It serves us well—and studies back this up—to know from the get-go that a salesperson, for instance, is unlikely to give us the information we really need. We know we need to get a broader view. And as we age, we get better at looking beyond the obvious, in part because of how our brains develop.

“It makes sense as we age,” says Reyna, “to rely on the part of our memories that is best preserved, and part of that is gist.”

Linda Fried, dean of Columbia University’s Mailman School of Public Health and a longtime expert in aging, says the abilities to see the vast canvas can foster creativity as well. We become more inclined to tie disparate threads together to make a new whole. “As you get older you can draw on objective knowledge and life experience and perhaps even intuition and they all get integrated and we can be more creative and solve complex problems that we could not solve when we were younger,” she says. “I think we even get better at recognizing those complex problems to begin with. It’s only when we are older that we have the patience and the strength and the willingness to go after the big core issues.”

In fact, some have watched this sort of brain integration, or wisdom, with their own eyes—or at least the eyes of a sophisticated scanner. One of the most passionate of the current crop of wisdom hunters, George Bartzokis, a UCLA neuroscientist, believes that whatever we call this—judgment, expertise, wisdom, magic—it happens quite naturally as our brains move into middle age. And it may be what gives humans our edge.

A lively, self-confident Greek who spent much of his childhood in Romanian refugee camps before coming to America, Bartzokis remembers seeing nature documentaries as a child and wondering, Why are we so different from, say, chimpanzees? Since we share nearly 98 percent of our DNA with the chimp, our closest relatives, what makes the difference?

Our brains are bigger in certain areas, most notably the frontal lobes. But what is it inside a human brain that makes that brain region work so much better than a chimpanzee’s? In fact, other animals—dolphins and elephants—have proportionately larger brains than ours. So what is going on?

Clearly, a large part of our human advantage comes not only from one brain part or another but also from the extensive system of connections—neural networks that build and strengthen, and allow us to keep a picture of, say, an entire air-traffic control system in our heads.

Insulating the Network

But while those basic networks—the gray matter—are crucial, it may be what holds those networks together—the white matter—that gives us our true advantage. No other animal has anywhere near as much white matter as we do. There are those, including Bartzokis, who believe it is the amount of white matter alone that has allowed us to develop such complex skills as language, for instance.

The white matter is made up of myelin—the fatty outer coating of the trillions of nerve fibers. The white matter acts as insulation on a wire and makes the connections work. Signals move faster and are less likely to leak out of a brain fiber that has been coated with myelin. This layer of fat, Bartzokis believes, is what makes the whole orchestra play together—and reach its cognitive crescendo—at middle age.

In a 2001 study, after scanning the brains of seventy men aged nineteen to seventy-six, Bartzokis found that in two crucial areas of the brain, the frontal lobes and the temporal lobes—the region devoted to language—myelin continued to increase well into middle age, peaking, on average, at around age fifty, and in some, continuing to build into the sixties. The study bolstered findings from years ago by scientists such as Frances Benes at Harvard who carefully measured the myelin of the brains she’d obtained from a nearby morgue. She, too, found that myelin continued to increase with age, and she, too, suggested that this might very well be what she called “middle-aged wisdom.”

How could a coating of fat do that? There’s little doubt that myelin is crucial in the brain. As a brain develops in childhood and neurons in the motor cortex are coated with myelin, the child becomes more coordinated, his hands more dexterous. When it starts to break down in diseases such as multiple sclerosis, for instance, a person can lose control of vital functions, such as balance.

The insulation allows the neuron to recover faster after signals have been sent and get ready to send the next signal more quickly, giving brain cells what Bartzokis calls “greater bandwidth,” and boosting their processing capacity by an astonishing 3,000 percent. This essentially puts us “online” and allows a more integrated and comprehensive view of the world.

And this myelination does not happen overnight. It’s a process. We build layers of myelin, and its architecture depends in part on how we use our brains. Myelin is produced by the glia cells in the brain, cells that cling to neurons and were for many years largely ignored by science. (Although there was a flurry of excitement a few years ago when, after Einstein’s brain was examined, scientists discovered that he had many more glia cells than are normally found in the logic areas of the brain.)

At a certain point, a type of glia called an oligodendrocyte sends out long tentacles that begin to wrap the neuron arm, or axon, in the fatty myelin. The wrapping continues, creating what looks like links of sausages. We all progress at somewhat different speeds in this process of myelination. There’s some evidence that females are better myelinators than males.

And recent studies confirm that myelin, while partly determined by our genetic blueprint, also thickens and becomes more efficient with deliberate use. As Michael Jordan was shooting basket after basket as he was growing up, for instance, it’s very likely that his basket-shooting neurons got more and more coatings of myelin. More myelin means better brain signals—and better basket shooting, in his case.

“You can have all the dendrites [brain branches] you want, but you need to connect them—and for that you need speed and bandwidth, you need myelin,” said Bartzokis. “This is what makes us human.”

In some cases, small segments of myelin can start deteriorating in our forties—indeed, as a relatively late evolutionary add-on, it’s particularly vulnerable to toxins. Its deterioration may lead to declines in cognitive areas. But through our forties and fifties and, if we are lucky and generally healthy, beyond, we also have an efficient myelin repair process. Until such maintenance breaks down, there’s a net gain of myelin that continues well into our sixties, particularly in that crucial area, the frontal lobes.

This overall myelin buildup, Bartzokis believes, is the “brain biology behind becoming a wise middle-aged adult.” A wise middle-aged human adult.

“It developed because it gave us an evolutionary advantage to have wise adults around who would not abandon their children to the lions,” Bartzokis said. “The middle-aged in the tribe had learned to control their impulses and not send all the children off to be killed in stupid wars, for instance, and that made them better leaders.

“In a way,” he adds,”we’ve always known this, but we’re just showing it now in science. Look at the Constitution. It clearly says don’t let anyone be president who is not at least thirty-five years old. The writers were not stupid. They looked around and said, ‘Hey, we can’t let anyone that young be president.’

“I’m fifty years old now myself,” Bartzokis adds, “and I do find I look at things with a much broader view. I see the whole big picture easier. That’s the formidable—the amazing—maturity of the middle-aged brain. That is wisdom.”