Read Present at the Future Online
Authors: Ira Flatow
MEMORY:
SENIOR JEOPARDY!,
ANYONE?
If you’ve played the TV game show Jeopardy!, you’ve probably noticed that your response time has been slowing down over the years. That’s because the brain changes with age. (That’s why I believe that we should have a “senior” version of the game, where folks older than 50 get up to 10 minutes to answer each question, because they just can’t seem to pull the answer—“I know it! Don’t tell me…”—out of their memory banks.)
Forgetting things isn’t all bad. (I’m not rationalizing just because I’ve always had a rotten memory. I’ve even forgotten names of people I’m interviewing—while I’m interviewing them!) In daily life, there are lots of things you don’t need to remember—such as phone numbers you’ll call only once or directions you’ll use only one time. You wouldn’t want to remember everything. That would be like saving all your junk mail.
Those dendritic trees make up different memory systems in your brain. When you experience something, the information enters your brain through different sensory pathways. The information fuses at some point into an integrated perception. When you remember something, your brain is stimulated to activate a certain pattern of neurons. Each time, that pattern is just a little bit different. Your memory doesn’t work like a videotape or a DVD, where exactly the same experience is replicated each time you play it. Instead, your memory is constantly changing and evolving as you accumulate experiences and as your neurons grow and change.
So it’s important to distinguish between memory loss (of which the major cause is Alzheimer’s disease) and change in memory. Memory is very much a matter of perspective. Where you’re standing, physically and emotionally, influences what you remember and how much. Consider how some memories are seared into your brain forever. For example, most people can tell you exactly where they were and what they were doing when they heard about the attacks on the Twin Towers and the Pentagon of September 11, 2001. In the same way, older people remember exactly what was happening around them when they heard that President Reagan had been shot, or President Kennedy had been assassinated. The emotions that accompanied those pieces of news are also why criminal investigators so often have to struggle with discrepancies among eyewitness accounts. Despite what you may have seen on Law & Order or any number of other television police procedurals, eyewitness accounts frequently vary dramatically—so much so that they are useless in convicting criminals. Eyewitness accounts may be inaccurate 40 to 60 percent of the time. Hard to base a life-and-death decision on percentages like that!
SENIOR MOMENTS
Why are all my friends and relatives who are over 40 convinced that they’re losing their memory? It’s actually quite rare to have anything seriously wrong with your memory. But memory does change. What
happens as we age is that there is shrinkage inside the brain. The neurons themselves become smaller. What’s affected is speed—how quickly the brain processes information. As the conduits—the neurons—grow smaller, the conductivity of neurons does slow down. Forgetting things as we grow older can be due to all kinds of reasons that have nothing to do with a serious illness such as Alzheimer’s disease. Stress, for example, can be a culprit. So can illness, or remedies for serious illnesses. General anesthesia and chemotherapy can result in temporary memory loss, or “chemo brain.” Heart and artery disease may be factors too if your brain is not getting enough circulation. But there’s no single cause; memory changes are very individual and happen for different reasons in everyone.
Dr. Aaron P. Nelson, chief of neuropsychology at Brigham and Women’s Hospital in Boston and assistant professor at Harvard Medical School, says that his patients bring him five complaints about their memories:
Dr. Nelson says he hears about these five types of memory lapses from as many as 90 percent of patients who seek him out. He emphasizes that none of these lapses means that anything significant is wrong with your memory. (I’ve added my own memory loss to the
list: “key-nesia,” where you can’t remember where you left the house or car keys. I think it deserves its own category. I even have discovered a quick and easy cure for key-nesia. In your haste to drop the heavy groceries, you don’t even look where you are dropping your car keys. Any place will do. So you never actually see where you left them. But if you watch where you put the keys, eye them carefully, you’ll never lose them. What about that theory, Dr. Nelson?)
He says new technology can help people like me who have name-nesia. A handheld recording device is a “no-brainer,” he says, to help you remember names. “You really shouldn’t be relying on your brain for that kind of information. It’s not what your brain was designed for. I’m totally reliant on my pocket PC. I consult it several times a day. For example, if I’m going to a social event, I list who’ll be there and something about each person. It works! When I get to the party, that information is in the foreground.”
THE GOOD AND BAD OF STRESS
Stress has a yin-and-yang effect on the brain. Too much stress can wreck your memory, says Nelson. “At very high and sustained levels, stress can cause actual physical and physiologic damage to structures in the brain that are important for memory. But at mild or moderate levels, stress actually can help memory function, believe it or not, because it kind of alerts you. It gets you to pay attention to something. It gets you to sort of label an event or an experience as important and worth remembering.”
You should worry, however, if you can’t remember information that is crucial to who you are, such as the name of your high school, “the name of a grandchild, some specific piece of information about where they worked for twenty years, that kind of a thing.” Or if someone tells you something, and a moment later, you have absolutely no recollection of what’s been said. That kind of memory lapse is more ominous and might spell real memory loss.
Nelson says that typically, people with more worrisome kinds of
memory problems are not the ones who seek help. “It’s usually someone related to them—a spouse, a family member.”
RX FOR YOUR MEMORY?
About 50 percent of how your brain ages is genetic. There’s nothing you can do about it. But that leaves 50 percent over which you have some control. The higher your intelligence and the more intellectually inclined you are, the less likely you are to lose core memory. In 2001, an ongoing study of 678 aging nuns found that those who had written more complex sentences in their early twenties were less likely to have succumbed to senility. And in 2003, a study of London cabdrivers—people who have to find their way around for a living—discovered that their hippocampi were larger than normal.
If you want to stave off memory loss, you don’t have to become a cabbie: Good nutrition and regular exercise are supposed to help, along with “use it or lose it”—the idea that you should stay mentally active. Some psychologists even give out “memory prescriptions,” mental calisthenics or daily exercises—push-ups for the brain—or advise getting involved in the poker craze. (Seventy-one-year-old Doyle Brunson beat 666 opponents to win the 2004 Legends of Poker Tournament.) Others believe that mental activity should become a habit, something you cultivate so that learning new things permeates all your activities. Getting involved in things that engage you, going back to school, trying something new, taking up something creative such as painting or jewelry design, playing games that involve planning and strategy, reading, joining debates and discussion groups—that’s what your brain is for.
If you stay mentally active, you build up connectivity in the brain that can protect you against a siege of disease. Some nuns in the 2001 study had brain scans that revealed traces of Alzheimer’s disease, but they showed no symptoms. Memory is about connections, associating one stimulus with another. The denser the physical
network, the “bushier” your dendritic trees, the more you can afford to lose before you show symptoms.
“What we’ve learned about memory echoes a lot of what we learned about cardiovascular health, in terms of brain health,” says Nelson. “Everything that we know that’s good for the heart is also good for the brain. So promoting optimal diet, exercise, managing stress—these things will all help ensure brain health as we age.”
There’s a lot of evidence, says Nelson, that ongoing intellectual activity may help stave off memory decay. “Whatever it is for you, something that engages your interests, something that engages your creativity, whether it’s learning something new, getting involved in a project that puts you in contact with new learning, new people. These are all things that are going to promote that kind of lifelong intellectual engagement, which is important.”
But what about cases like that of Dame Iris Murdoch? The famous British novelist’s descent into Alzheimer’s disease was the subject of the 2001 Oscar-winning film Iris. A prolific author of highly intellectual novels, Murdoch certainly had been mentally active. (As the movie illustrates, she exercised too: All her life, she loved to swim, even in old age.) Amazingly, a new study has found that daydreaming and woolgathering—something writers and teenagers are very prone to—may overwork and decay your hippocampus, the part of your brain most affected by Alzheimer’s disease. So letting your brain idle—and not be focused on completing a task or reading or carrying on a conversation—could hasten the onset of Alzheimer’s disease! On the plus side, the study may offer a way to diagnose Alzheimer’s disease early, before symptoms become obvious.
Another possibility in Murdoch’s case is that her mental acuity did give her greater resistance and she successfully held off her illness for years—until it finally overwhelmed her. Recent studies also have found that when people with a high degree of cognitive reserve are finally overcome by this disease, they fail very quickly. Nelson says there’s been some interesting research out of Columbia University
since the late 1980s on what’s called “cognitive reserve.” “Here, the notion is that being involved in lifelong learning and keeping intellectually engaged makes a difference. It certainly can push you off the onset of Alzheimer’s disease. We know that people with high levels of cognitive reserve can resist symptoms of Alzheimer’s disease despite an equal or greater amount of brain pathology in the people who have the low levels of cognitive reserve. And this all has to do with both genetic and acquired intellectual interests.”
As for nutrition, Nelson believes that there is good evidence of the importance of maintaining enough B vitamins in your diet. And if you can’t get the vitamins from food, supplements are a good way to go. “One of the things we look for in patients presenting with memory complaints is what their nutritional status is, what they’re eating, maybe what they’re missing. It’s important.”
IS IT IN THE GENES?
I blame my name-nesia on my mother. She has had name recall problems for decades. But what about serious diseases, such as Alzheimer’s disease? If any of your parents or grandparents are afflicted, does that mean you’re going to automatically get it yourself? “Not at all,” says Nelson. “The majority of Alzheimer’s disease is sporadic. It doesn’t have at least an obvious genetic connection, a familial connection. Certainly having a relative with Alzheimer’s disease does increase your risk, but it’s not anything like the type of genetic determination that we see with other illnesses. The genetics of Alzheimer’s disease are extremely complex. We don’t really have it worked out yet, but at this point, having a relative with Alzheimer’s disease does not absolutely seal your destiny as having it yourself.”
THE COLOR WHEEL
You may remember the color wheel from art class in grade school. You can find color wheels in art-supply stores, and craftspeople frequently rely on them when they work with colored paper, fabric, or
beads. But you probably didn’t know that the color wheel illustrates how the human eye and brain work. Early-twentieth-century German painter and color theorist Johannes Itten, a member of the famous Bauhaus School, invented the color wheel. Itten based his work on the research of Sir Isaac Newton and of physiologist Ewald Hering, who studied color blindness. Itten’s color wheel is a visual tool made up of 12 colors. It starts with the 3 primary colors equidistant from one another: red, yellow, and blue. Mixing 2 primaries creates a secondary color, also equidistant from each other: purple, green, and orange. Mixing a primary color with a nearby secondary color creates a tertiary color. The 6 tertiaries are yellow-orange, red-orange, red-purple, blue-purple, blue-green, and yellow-green.
The color wheel helps demonstrate the phenomenon of “successive contrast,” which happens when the brain creates an afterimage of a color when you look at it for an extended period of time. Green, for example, is the afterimage of red. (In Florida, you hear about the “flash of green” that supposedly you can see immediately after the sun sets in a blaze of red.) On Itten’s color wheel, that afterimage is always the color’s complement.
Try using the color wheel to come up with a split-complementary color scheme of your own choosing. Pick a key color. Then go directly across the color wheel to find its complement. Instead of the complement, use the two colors next to it. Itten recognized that the brain finds color equilibrium and recognizes harmonies. But of course, everyone sees color somewhat differently. Itten thought that his color wheel would help “liberate” painters and designers from “indecision and vacillating perception.”