Successful aging: THE SECOND 50
The 16th century Spanish explorer, Ponce de Leon, marched off in search of the fountain of youth, only to discover death. Intruding into hostile Indian territory in Florida, de Leon was killed by an arrow at age 47.
But today millions of Americans are experiencing the longer life that eluded de Leon. In fact, the percentage of Americans age 65 and older has more than tripled in the last 100 years, and now represents 13 percent of the population.
Not only are more people living into the second 50 years of life, 70,000 centenarians have entered their third 50 years. And by 2050, the U.S. Census Bureau estimates the number of centenarians at 834,000 - although the bureau’s “high-end” calculation predicts that figure could climb as high as 4.2 million.
The urgency, now, has begun to shift from that of medically prolonging life to ensuring that a prolonged life is worth living.
Psychological researchers are attacking the problem along several fronts, and some of the most practically applicable work has come from the field of memory and cognition.
“It is cognitive capacity, more than any physical disability,” says Margery Silver, EdD, a neuropsychologist at Harvard, “that most often determines whether people can attain extreme old age while remaining active.”
Thus, studies in this area range from better understanding mental functioning, to the importance of social support in keeping memories sharp, to the basic review of everyday activities, such as the way we use ATM machines or solve crossword puzzles.
Psychologists are proving almost daily that humans in their later years have far more physical and mental strength than imagined. They are showing that memory loss can be reversed by personal strategies such as daily memory checks and regular mental exercises. And they’re designing methods to help people change their behavior to take advantage of increased longevity.
HOW IS SUCCESSFUL AGING DEFINED?
Although “successful aging” was not an explicit theme in the biomedical literature until the early 1960s, there have long been efforts to understand how to promote longevity and positive states of health in later life. The writings of ancient philosophers reveal disagreements in views of positive emotional outcomes in later life. Aging has been described as a largely intractable process versus one involving possibilities for adaptation to new roles. Modern psychiatrists and psychologists considered later life either as a product of early developmental tasks or as a period of continued growth and conflicts that had to be negotiated.
In the 1970s and 1980s, formal models of successful aging emerged. In their influential 1987 article, Rowe and Kahn noted that research on aging was historically dominated by efforts to discriminate between pathological and “normal” aging, with little effort being devoted to understanding the upper end of the continuum (i.e., successful aging). Successful aging was characterized as involving three components: a) freedom from disease and disability, b) high cognitive and physical functioning, and c) social and productive engagement. The MacArthur Network on Successful Aging operationalized these criteria, and followed over a period of seven years a sample of 1000 older adults who met the criteria. Another prominant model of successful aging proposed around the same time period was that of Baltes, who described successful aging in terms of lifespan developmental trajectories, with a focus on behavioral and psychological adaptation to losses.
“There are innumerable important questions about health and aging that psychologists are poised to answer,” says researcher, Denise Park, PhD, of the University of Michigan.
Decline not inevitable
In fact, a new paradigm, centering on the idea that memory and cognitive power don’t necessarily decline with age as traditionally thought, is taking hold within the psychology community.
That concept gained momentum with study results released last fall by a team of Princeton University psychologists. They found that adults continue to grow new brain cells throughout life. Those late-generated cells, they found, may allow older people to bolster their learning and memory capabilities, or even to stave off declines. Such capabilities were never envisioned under the old theory that cells stopped forming - and actually started dying - by age 40.
The byproduct of that report - by Elizabeth Gould, PhD, Alison J. Reeves, Michael S.A. Graziano, PhD, and Charles G. Gross, PhD, in the Oct. 15 issue of Science (Vol. 286, No. l, p. 548-552) - has been hope among researchers.
Why? John Cavanaugh, PhD, a researcher on aging issues at the University of North Carolina at Wilmington, believes the answer lies buried in memory, and filed under “Beliefs.”
“With memory, it does appear that people’s belief systems are important,” says Cavanaugh. “There are hints that the kinds of things people tell themselves [about their ability to remember] matter.”
Older people, for instance, might believe their memory and intellectual power is insufficient, and therefore may avoid learning how to use a computer, or may shy away from a training course in strategies for learning and retaining new information.
“The stereotype is that memory is supposed to decline,” adds Cavanaugh, “but that’s still an open question.”
Peter Martin, PhD, a professor of human development at Iowa State puts it even more bluntly: “No matter what your age, the memory is still trainable. You can teach an old dog new tricks.”
Pursuing that theory, researchers are studying the value of having older adults develop memory strategies, perform a daily self-monitoring of their memory and carry out regular mental exercises - for example using associations with one or more of the senses, to encode information into memory.
“But people have to make a conscious decision to do this,” says researcher Robin West, PhD, at the University of Florida. “It’s not going to occur automatically.”
In the meantime, other researchers are approaching the memory puzzle by looking beyond the strategic to the very tactical issues faced in everyday life. A group of Georgia Tech researchers, for example, used the daily crossword puzzle as a model for studying differences between young and old in “novel problem-solving” and in memory recall.
Timothy Salthouse, PhD, and David Hambrick, PhD, of Georgia Tech, whose report appeared in the Journal of Experimental Psychology (Vol. 128, No. 21, p. 131-164), were surprised to find no evidence that crossword puzzle-solving reduced, in older adults, the known age-related decline in problem solving ability - nor did it increase the known age-related gains in stored memory.