But even while it outperforms its younger self in many ways, the middle-age brain gets a bad rap. It's true that we can lose our focus or get distracted more easily as we age, but there is plenty of emerging and established science to show that people underestimate the formidable talents of the mature brain, says Barbara Strauch, author of "The Secret Life of the Grown-Up Brain" (Viking, 229 pages, $26.95).
"The world has to wake up to the fact that middle age is not dead. We're wasting the best brains of our lives. We should appreciate them," Strauch said in an interview from her Manhattan office. Strauch, deputy science editor at the New York Times, makes the case for the middle-age brain by delving into the exploding field of brain science and reporting on a spectrum of research and analysis.
Strauch reports that our brain powers up, not down, and grows in cognitive ability as we age, reorganizing itself and using more of its parts to solve problems - even excelling at the teenage art of multitasking. Studies are proving that our brains reach peak performance between the ages of 40 and 68, the period commonly defined as middle age by researchers. The brain continues to grow even as we yearn for the bygone days when we could remember the movie we saw the weekend before.
While some people do slip mentally in midlife, the message of neuroscience today is that the human brain is highly variable. Even in our early 70s, the average age when cognitive decline is seen, some of us roll along without symptoms of decline, apparently tapping superior repair systems. So, while the brain does slow down, with the growth in cognitive depth and reasoning power, there's a "net gain" in middle age, Strauch said.
Strauch became interested in exploring the grown-up brain after listening to her middle-age friends complain about memory problems. Yet her friends were hardly failing in life. In fact, they excelled in their often complex professions and managed to handle household finances, rear kids, navigate gourmet recipes and organize school auctions. She was curious about what powered their abilities.
She cites a growing acceptance of the idea of a "cognitive reserve," something like an emergency stash of brainpower that helps the mind adapt to greater challenges and resist damage. Tapping that reserve may provide a buffer against the outward symptoms of mental decline, some research shows. Additionally, a beneficial fatty white coating on the brain called myelin continues to grow, insulating the brain's long arms of nerve fibers as we age into our 50s and 60s and, in some cases, beyond.
"Signals move faster and are less likely to leak out of a brain fiber that has been coated with myelin," Strauch writes. One prominent researcher believes this layer of fat "is what makes the whole orchestra play together - and reach its cognitive crescendo - at middle age."
"The Grown-Up Brain" includes studies about measures people can take to stay mentally supple in their later years (see box). Exercise is high on the list because it prompts blood flow to the brain and promotes the birth of new neurons. Mental challenges - the more complex and diverse the better - and social interaction activate the brain's neurons. There are hints that something as simple as education may help protect the brain in later years, although no one suggests it will prevent the pathology of a disease like dementia, Strauch said. Some research shows that a diet rich in omega-3 fatty acids or taking medicine that lowers blood pressure may be beneficial.
However, an independent panel of the National Institutes of Health recently cautioned that studies on preventive strategies are inconclusive and that more research is needed on how to keep our brains healthy.
Our outlook on life may also have a big impact on the health of our brains. Scientists have linked emotional well-being with mental alertness and lower risk of Alzheimer's disease. On a bright note, Strauch said she was surprised to learn that no credible science backs the inevitability of the midlife crisis or the empty-nest syndrome. In fact, the aging brain appears to selectively focus on positive memories rather than on stress or negativity, Stanford psychologist Laura Carstensen found. The brain appears to regulate emotion, with research finding increased feelings of well-being between the ages of 40 and 60.
"We're brought up to think it's going to be doom and gloom" when the kids are grown, Strauch said. But midlife crisis affects only 5 percent of the population, and people in middle age generally feel they have a greater sense of control over their lives. As one researcher in Strauch's book says, "By midlife we are equipped for overload."
Things that help keep the brain fit and alert. E3
Gaming the brain helps it, studies show
The search for brain-boosting activities has fueled a boom in commercial brain games. But proving that these games work, especially in real-life situations, is not easy, says Barbara Strauch.
In one study conducted by the University of Southern California, researchers found that a rigorous computer program developed by neuroscientist and former UCSF Professor Michael Merzenich did improve cognitive test results.
"If you challenge your brain in the right ways, it will respond," said Steven Aldrich, CEO of Posit Science ( www.positscience.com), a San Francisco company Merzenich co-founded to offer the computer training.
Posit Science's computer program uses sound and image recognition in increasingly difficult patterns to sharpen the brain's cognitive abilities. Incoming signals to the brain can get fuzzy as we age. The aim of Posit's program is to force the brain to focus, thereby stimulating production of beneficial chemicals that sharpen the information stored as memory. The company says people who trained on the driving exercise in its program had fewer real-life accidents than a control group.
- Rita Beamish
Keeping your brain alert
Break a sweat: "In one rigorous study after another, exercise has emerged as the closest thing we have to a magic wand for the brain."
Just as physical activity benefits the heart, it also carries oxygen to brain cells and appears to increase brain volume. In one study, mice that exercised on a wheel produced new brain cells.
Challenge the cells: "Most evidence now suggests that we can boost our brain reserve, even when older."
People who push their brains beyond the comfort zone to learn new things and solve new problems exhibited fewer symptoms of dementia in some studies. Crossword puzzles are not enough: They only challenge you to recall words you already know. The brain falls into a rut by repeating the same activities.
Keep talking: "Being sociable is good for both body and mind."
One study in England found that middle-age people who regularly popped into their neighborhood pubs had better cognition than their stay-at-home neighbors. Social complexities and interactions constantly tax the brain.
Mind your mood: "Our moods are surprisingly important to our brains."
People who are less grumpy or happily entwined with others - or a pet - have a lower risk of developing Alzheimer's disease and are more mentally alert. A positive self-image is also linked to better memory. Depression and stress, on the other hand, are linked to shrinkage of the brain's memory-rich hippocampus.
Nutrition confusion: "It's hard to think of a topic more steeped in hope and hype than the brain and food."
Researchers continue to look for clear-cut guidance for humans, but animal studies point to the benefits of fruits, vegetables, nuts and other foods rich in antioxidants. In studies on rats, those that ate dried spinach learned new tasks faster and those on blueberry diets produced new brain neurons. In another study, old dogs learned new tricks better when their diets were fortified with tomatoes, carrots, citrus pulp, spinach and vitamins E and C.
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