For a Healthy Brain, Play the Long Game
Psychologists are learning that the brain stays agile well into middle age, retaining the ability to learn new skill sets and take on different points of view by building new neural connections. And nothing is more important to maintaining a healthy brain than receiving an education, say psychologists. Up to age 75, mental tests demonstrate that ‘people with college degrees performed on complex tasks like less-educated individuals who were 10 years younger.’ In other words, learning keeps you young.
What’s the Big Idea?
A greater understanding of intelligence has come to light in recent years which distinguishes between what psychologists refer to as fluid and crystallized intelligences. While fluid intelligence—memory and abstract thinking—peaks in your 20s, crystallized intelligence—inductive reasoning and judgement—continues to build until very late in life. Perhaps most encouraging of all is that the brain remains ‘fluid’ until much later than was previously thought, retaining the ability to forge new neural connections through new experiences.
Some people are much better than their peers at delaying age-related declines in memory and calculating speed. What researchers want to know is why. Why does your 70-year-old neighbor score half her age on a memory test, while you, at 40, have the memory of a senior citizen? If investigators could better detect what protects one person’s mental strengths or chips away at another’s, then perhaps they could devise a program to halt or reverse decline and even shore up improvements.
Many researchers believe that human intelligence or brainpower consists of dozens of assorted cognitive skills, which they commonly divide into two categories. One bunch falls under the heading “fluid intelligence,” the abilities that produce solutions not based on experience, like pattern recognition, working memory and abstract thinking, the kind of intelligence tested on I.Q. examinations. These abilities tend to peak in one’s 20s.
“Crystallized intelligence,” by contrast, generally refers to skills that are acquired through experience and education, like verbal ability, inductive reasoning and judgment. While fluid intelligence is often considered largely a product of genetics, crystallized intelligence is much more dependent on a bouquet of influences, including personality, motivation, opportunity and culture.
One of the brain’s most powerful tools is its ability to quickly scan a vast storehouse of templates for relevant information and past experience to come up with a novel solution to a problem. In this context, the mature brain is especially well equipped, which is probably why we still associate wisdom with age.
Indeed, mental capabilities that depend most heavily on accumulated knowledge and experience, like settling disputes and enlarging one’s vocabulary, clearly get better over time. If you’re looking for someone to manage your financial portfolio, you might be better off with a middle-ager than a fresh young M.B.A.
Richard E. Nisbett, a cognitive psychologist at the University of Michigan, has long argued that when it comes to intelligence, experience can outrun biology. A recent study he wrote with Igor Grossmannon aging and wisdom concluded: “Older people make more use of higher-order reasoning schemes that emphasize the need for multiple perspectives, allow for compromise, and recognize the limits of knowledge.” Most important, they discovered that despite a decline in fluid intelligence, complicated reasoning that relates to people, moral issues or political institutions improved with age.
Regular mental workouts can actually alter the brain’s neural circuits in middle-age and older adults, making regions like the hippocampus, a center for memory and learning, more responsive. Cognitive exercise also helped improve executive functioning, the kind of decision-making ability associated with a mission control center.
Senior citizens who performed as well as younger adults in fluid intelligence tended to share four characteristics in addition to having a college degree and regularly engaging in mental workouts: they exercised frequently; they were socially active, frequently seeing friends and family, volunteering or attending meetings; they were better at remaining calm in the face of stress; and they felt more in control of their lives.
Just as money and education often run together, these factors tend to reinforce one another. Adults who call on friends and family for support may be better able to reduce their stress, and reducing their stress may give them sense of control.
“When young adults think about college, they think about career opportunities and possibly the social benefits. What they don’t realize is college education has long-term benefits well beyond first job and social contacts.” The same could be said for continuing education.
At a time when the prospect of a longer life is shadowed by the fear of mental decline, the possibility that the aging can have some control over their mental fitness is an idea even William Osler would support.
There is no preordained march toward senescence.
By Patricia Cohen is a reporter for The Times