Research confirms that attitude, not estrogen, is what will keep you sharp.
Memory & Aging Research
When we're constantly being barraged by ads for products like Senior Moment and Focus Factor -- not to mention an onslaught of hormone-therapy alternatives that claim to stabilize radical mood swings, along with other menopausal symptoms -- it's no wonder that some of us have come to expect the worst. But are we really doomed to face a downward spiral of mounting depression and confusion?
On the contrary, say the experts. Not only is there no cause for alarm, but the reality may be far better than you think. After years of having the medical community characterize menopause as an illness in need of treatment, research is shedding new, often positive, light on what this biological transition really means to our health. The findings about your brain: Menopause itself does not cause memory loss or depression; overall brain functioning remains consistent and strong in healthy people well into old age; and many of the changes that may occur are controllable or even reversible.
"One of the most pervasive stereotypes about aging is that it causes memory decline," says Thomas Hess, PhD, professor of psychology at North Carolina State University in Raleigh, who conducted a three-year National Institute on Aging-funded study. According to Hess, a woman's attitude toward aging may be the best predictor of how she'll fare. In his study, older adults who read a fictional but very negative article on memory and aging performed significantly worse on subsequent memory tests than those who read an equally bogus but positive article on the subject. "If people are exposed enough to a stereotype, they begin to believe it," he says.
In another recent study, published in the journal Neurology, researchers at Rush University Medical Center in Chicago expected to see an overall decline in cognitive functioning as the 803 women they tracked for two years passed through menopause. Instead, they discovered that, on average, subjects' scores on a variety of periodic memory tests actually improved. "If women do have memory problems as they age, there's no indication they're related to hormonal changes," says study author Peter Meyer, PhD, a biostatistician at the Center.
Whether estrogen plays a role in maintaining a healthy brain is still up for debate. The FDA recently added a warning to hormone therapy (HT), indicating that it might increase the risk of dementia. But studies offer very mixed reviews. Some scientists are still investigating a "critical-period" theory, with the idea being that taking HT during a certain part of the perimenopausal transition might ward off dementia and Alzheimer's, whereas taking it later might worsen memory loss.
Life circumstances appear to be a bigger threat to midlife memory function than estrogen decline, says Barry Gordon, MD, PhD, professor of neurology and cognitive science at Johns Hopkins University and author of Intelligent Memory (Viking, 2003). Worries ranging from empty nest syndrome to caring for aging parents can divert valuable mental resources away from focusing on the task at hand, so that a memory doesn't have a chance to become ingrained.
Research on depression is reaching similar conclusions. Study after study, from Australia to the U.K., show that depression and other mood disorders are biologically unrelated to menopause. A series of surveys of 438 midlife women in Melbourne, for example, consistently demonstrate that negative mood scores relate neither to menopause nor to hormonal changes, but instead often correlate with pessimistic attitudes about aging, negative feelings for one's spouse or partner, lack of exercise, and high stress levels. Researchers analyzing data from the Seattle Midlife Women's Health Study concur with that conclusion, noting that, "For most women, the menopausal transition was not a time when there was a new episode of depression."
Brain Changes as We Age
Of course, no one denies that the brain, like the rest of the body, does change with age. Most researchers accept the notion that as people get older, they experience a general decline in the speed with which they perform various cognitive tasks. However, procedural memory (which involves things we do without thinking, like knowing how to read or making quick associations) generally tends to resist aging and diseases of the brain, according to Gordon. Working memory -- which centers on processing, storing, and recalling information -- and episodic memory, which entails recalling a recent past experience, seem to erode more quickly. For example: You look up a phone number but are interrupted before you make the call. Remembering the number after the interruption would be a successful use of working memory. Episodic memory is being able to remember what you had for breakfast or what route you took home yesterday.
A number of neuroimaging studies back up these assertions. Scans of older adults show gradual tissue loss, or declines in tissue densities, in the frontal, temporal, and parietal regions of the brain, which are all involved in working and episodic memory. Other imaging studies have shown decreased (or alterations in) activity in the left frontal cortex, which is involved in working memory processing. Researchers at the University of Edinburgh have found that age-related abnormalities in the white matter -- the substance that transfers information between different regions of the brain -- are also linked with such health problems as hypertension. This suggests that such abnormalities might be preventable, at least to the extent that high blood pressure and other circulatory problems can be controlled. Although the significance of these defects is unclear, having many of them has been associated with cognitive decline.
Still, the Scottish study and others, like the Seattle Longitudinal Study of Adult Intelligence, show that aging deficits tend to be small and gradual. In the Seattle study, declines in a range of cognitive abilities were generally not seen before age 60, and by the time subjects reached 74 only small changes were observed. Even at age 81, less than half of the adults showed significant declines over the previous seven years.
Healthy Body, Healthy Mind
The study findings of the last few years underscore the importance of recognizing that many changes can be controlled or reversed. Simple modifications in lifestyle -- namely, exercise (both physical and mental) and stress reduction -- can go a long way toward keeping your mind fluid and fit. Physical ailments can have profound effects on cognitive functioning. The Scottish researchers note, for example, that hypertension might account for part of the effect of white matter abnormalities on cognition. And they observed that twins in their study with conditions such as higher blood pressure and poorer glucose tolerance in midlife had more white-matter abnormalities in old age. Other research has shown that men in their 40s with even mildly elevated blood pressure were more likely to have significant signs of brain aging in their 70s.
Staying physically fit can have tremendous rewards. MRIs have shown that adults who exercised more had significantly slower rates of brain-tissue loss, and animal experiments have found that nerve growth factors in the brain increase with exercise. Arthur Kramer, PhD, a professor of psychology and neuroscience at the University of Illinois in Urbana-Champaign, found that walking between 45 minutes and an hour just three days a week for six months was enough to induce positive changes. Other lifestyle changes, such as eating a healthy diet, may also keep glucose levels, cholesterol, and hypertension in check -- and in turn protect the brain.
Mental exercise also has its rewards. In the largest study of its kind, research funded by organizations including the National Institutes of Health revealed that several types of cognitive training (involving memory, reasoning, or speed of processing) were able to significantly improve memory, concentration, and problem-solving skills. In their study of more than 2,800 adults age 65 and older, those who had gone through weekly two-hour training sessions for five weeks performed significantly better on a variety of cognitive functioning tests, and those benefits persisted for two years after the training ended.
Another recent study at Washington University, involving brain scans, indicates that older adults often do not use regions of the brain best suited for memory processing. But with test aids and training they are able to use these areas more effectively, and regain the ability to create new memories. "Older adults appear to have plenty of underutilized cognitive resources that can be harnessed and used for more efficient memory processing," says Randy Buckner, PhD, professor of psychology at Washington University and senior author of the report.
Hilary Macht Felgran has also written for The New York Times and The Columbia Journalism Review.
Originally published in MORE magazine, May 2004.