In the last decade, improved imaging technologies have given scientists a new window on the brain, and Restak has turned the latest research into a practical guide for brain health. In Think Smart: A Neuroscientist’s Prescription for Improving Your Brain’s Performance, the neurologist, neuropsychiatrist and professor of clinical neurology at George Washington University Medical Center explains that, like any body part, the brain needs regular workouts to keep in shape.
The brain’s enemies aren’t added years, Restak says. Rather, distraction, sloth, stress, boredom, even obesity and loneliness are the bugaboos that can dial down mental productivity. Depression, in fact, can actually shrink the hippocampus—part of the brain that plays a major role in memory and spatial navigation. [Read an excerpt from the book.]
We need to care for that three-pound organ above the eyes, Restak says. After all, it has a hundred billion cells with a million billion connections between them instructing us on everything from brushing our teeth to recalling names to running a marathon to writing a novel. Restak spoke with AARP Bulletin Today about his prescriptions for boosting intelligence, memory and fending off age-related decline.
Q. What have been the biggest surprises about the brain in the last decade?
A. We’ve learned how plastic the brain is, how much it can change. As we’re talking right now, sharing new information, our brains are changing, creating new connections between neurons. We used to think you were born with a certain capacity for intelligence, but now we know you can continually enhance it. You can better your mental acuity, your speed of processing information and your memory.
Q: How so?
A: A whole host of ways. Play golf. Knit. Dance. Enjoy card games, board games, even video games. Socialize. Practice better concentration. Sleep. Puzzle over brainteasers. Think “outside the box.” Work if you can. Eat healthy food and drink wine moderately. Turn stresses into challenges. Feed your curiosity and study new things. Sounds like a great way to live, doesn’t it?
Q: We often think of older, more mature brains as losing faculties, but does a brain that’s been around longer have advantages?
A: Another surprise. We all start out with a large number of cells, of neurons, and over time many are lost. Yet as we mature, the brain can actually work better. It compensates for losses by increasing the networking capacity of the neurons you have left, so you have fewer but stronger connections. I can’t think of anything else that runs better after it loses parts. The brain is really unique in this way.
Q. How much power, then, do we really have over how well our brains work?
A. Quite a bit. First, we have control over the basic elements of intelligence. Attention is the bedrock of intelligence. The more we learn to focus in a world of distraction, the smarter we get and the better our brains function. Memory then follows naturally from attention. Clearly, if you don’t attend to something, you can’t remember it. Attention also allows you to improve performance in other brain functions. Sensory memory, long-term and short-term memory, fine motor skills, observational skills, the ability to reason—if you work them, they will improve.
Q. Does working to improve memory help other brain functions?
A. One kind of physical exercise—say, swimming—may bring about improvements in general health, such as blood pressure, respiration and metabolism. But mental exercises need to be more focused. If you spend time working your memory, it won’t do much for your power of logic or hand-eye coordination. You have to focus on each component separately.
Q. Long-term memory obviously has the tightest grip on information. Is there a limit to what our long-term memories can hold?
A. Actually, you can store as much information as you want in your long-term memory—the information that becomes a permanent part of you—without ever exceeding its capacity. It is essentially infinite. That doesn’t mean you can recall everything that you’ve ever learned; sometimes you simply can’t access the memory. People with “good” memories don’t necessarily have more data stored. They are just better at getting to it. The easiest memories to retrieve are often linked to an image or an emotion.
Q. What role does sleep play?
A. For so long we had the wrong idea about sleep, that it is down time, a waste of time. But think of the brain like a tomato. In the day it collects sunlight, goes through photosynthesis and so on. Then the sun goes down and all this restructuring of proteins takes place that allows the tomato to grow. The brain is like that, too. It takes in information while you’re awake, but then it needs to structure and lay that information down.
Q. And that takes a good night’s sleep?
A: It’s best to have at least six hours of sleep between learning activities. So if you take a tennis lesson, don’t take a golf lesson right away—and best of all, take a nap in between. Naps can be as effective as longer sleep for holding on to information. We’ve seen a 16 percent improvement in ability if a person takes a nap after learning a new skill.
Q. What about retirement? Do we lose brain function if we aren’t going through the motions of a job?
A. The ideal retirement, though not possible for many, is gradual. The workplace offers all kinds of challenges, positive and negative, that keep your brain sharp. Socialization is part of it. So when I talk to people about retiring, I ask how happy they are with their work. If they are generally happy, I say they should try to go on a little longer. But if a job is very stressful, then the brain benefits from getting out from under that load.
Q. Where are we with treatments for neuropsychiatric diseases like Alzheimer’s?
A. For the majority, we’ve come up with treatments that can slow the process. If you slow a disease’s process by 30 percent for someone in their 80s, that’s extremely helpful. Importantly, no one is certain when Alzheimer’s actually starts. It may start much earlier than we realize. What some doctors call mild cognitive impairment others see as a precursor to real disease. But it’s also important to know cases can be mild or slow.
Q: Are there actual ways to ward off dementia?
A: Most important, your knowledge base, your intelligence, matters. With Alzheimer’s, we find that more educated patients may have a lot of damage to brain tissue before they begin to show symptoms. It’s like having money in the bank when a financial crisis hits. Building up a strong cognitive reserve helps you withstand the physiological changes in the brain for longer.
Q. How can you tell the difference in loved ones—or yourself—between regular forgetfulness and signs of a real problem?
A. You have to look for real change. If someone is just a little worse than he or she used to be, that’s not as worrisome as a major change in someone who had a super power memory. We all come out of the mall and can’t remember where we parked, probably because when we arrived we were preoccupied with what we were going to buy. But if you come out and can’t remember if you drove or took the bus or someone dropped you off, that’s beyond normal forgetting. That suggests a more serious problem.
Q. What’s the best way to respond to a loved one who is having real memory difficulties?
A: You don’t want to be confrontational or argumentative. Often there’s a sense of panic on the part of the other person, who deep down fears becoming that way himself or herself. Simple correction, neutral correction to the memory lapse is best. Often it’s best not to say anything about the incident, unless it’s something really important.
Q. In addition to video games and brain teasers, what are some things you do to help your own brain health?
A. My work as a neurologist and my writing help me to keep mentally sharp. I don’t plan to retire from either of these activities. I eat well—with the occasional deviation, like frozen yogurt or especially good cake. I also see great value in exercise—mostly, I take long walks. And I follow my own advice about having a “magnificent obsession”—something not necessarily linked to your work about which you build up knowledge. My obsession is magic, which I enjoy because it incorporates surprise, concealment and mental expectation.
Q: What about attitude?
A: Most important, I try to maintain a state of equanimity. Stress is the biggest contributor to poor health, dementia and a premature death, I am convinced. I’ve reached a point in my life that I no longer have to prove anything to anybody other than myself. Such an attitude enhances achievement because it greatly reduces internal stress. Once you’re no longer afraid of failing, winning becomes all that much easier.
Jennifer S. Holland is senior staff writer at National Geographic magazine specializing in biological sciences and natural history.