Keeping Aging Minds Sharp
Laura L. Carstensen
HMS Beagle, Issue No. 90 (November 10, 2000).
Research findings suggesting that aging doesn't have to be linked to declining cognitive ability come as good news. As our population grows older, a strong, interdisciplinary research focus on understanding the aging mind should be a priority.
"I'm having a senior moment." We've all heard that one, and the countless other jokes about getting old. In our culture, it is generally accepted that older people will gradually begin to forget things or become less logical in their thinking. We take it for granted that aging minds grow a little fuzzy around the edges.
But exciting new research indicates that growing older might not necessarily have to mean growing mentally slower. New studies are providing breakthroughs in our understanding of how aging affects memory, language, and other cognitive functions. This information could provide tools for lessening or even averting some loss in brain functioning often associated with old age.
And that's good news, considering the enormous growth the United States is facing in its proportion of elderly people. Figures from the U.S. Census indicate that the number of people over age 65 will reach 70 million by the year 2030 -- more than double current numbers.
If science can help older citizens retain their mental abilities longer, then the whole nation would benefit. That's why it is so important for research on the aging mind to flourish. The government should make studying neural health, the role of life experiences in shaping the brain, and the structure of the aging mind key priorities in the coming years. And the National Institute on Aging should undertake major research initiatives in these areas to expand the scientific basis for understanding and promoting healthy mental aging.
Revolutionary advances in neuroscience, behavioral science, and the science of learning have opened the door for the development of new techniques and technologies that can preserve mental sharpness in older people. These might be as novel as transplanting genetically engineered cells to replace dysfunctional neurons, or as familiar as engaging in stimulating intellectual and physical activities.
As the many jokes about losing brain cells illustrate, it has long been thought that age-related decline in cognitive abilities is a result of diminishing neurons and synapses. But scientists have discovered that as people grow old, a drop in certain mental abilities may have more to do with changes in the health of the nervous system. For example, the mild loss of memory often associated with growing old may be linked to biochemical shifts in neurons rather than to actual loss of brain cells. Research aimed at identifying the mechanisms that maintain or impair neural health is critical for advancing our knowledge of aging.
In addition, exciting studies under way around the country are exploring the degree to which older people can benefit from certain kinds of mental practice. We are only beginning to understand the pliability of cognitive functioning in people who are already old, but the promise of finding ways to maintain abilities is very real. For example, studies indicate that our life experiences can bring about lasting changes in our brains that shape how we age. Aging people with college or post-graduate degrees, for instance, generally have better cognitive functioning, such as language and reasoning, than those with less education. And better-educated people who reach their 80s -- when much of the decline in brain functioning typically occurs -- experience far fewer cognitive problems than their less educated peers. Scientists believe that formal education and professional training lead to more dense and complex associations among neurons that maintain functions even when those associations weaken.
But to continue these advances, scientists must work together across disciplines. The days of Renaissance scientists are long gone. Government funding mechanisms should encourage cooperation across a broad spectrum of social and natural sciences. Advances in these sciences come about so rapidly that researchers must work in interdisciplinary teams to address important questions most effectively. Breakthroughs like neurogenesis -- the appearance of new neurons in later life -- show that under some conditions brain functioning not only can be preserved, but also that new growth can occur. Such findings demand greater understanding of the biological mechanisms involved, to be sure, but they also demand sophisticated understanding of their cognitive and behavioral consequences.
Clearly, this is a time of great promise for learning about how our brains mature. Even more important, this knowledge can -- and should -- be used to make life better for as many older people as possible. Humanitarian reasons aside, however, the demographic changes under way in this country mean that the functioning of older people will influence the entire society. The government should make the study of aging minds a top priority.
Laura L. Carstensen, Professor of Psychology at Stanford University and the Barbara D. Finberg Director of its Institute for Research on Women and Gender. She recently chaired the National Research Council Committee that wrote the report The Aging Mind: Opportunities in Cognitive Research.
1. The Aging Mind: Opportunities in Cognitive Research - the National Academies' Report from the Committee chaired by Prof. Laura Carstensen.
2. In Search of the Secrets of Aging - An Introductory Text from the National Institute on Aging covering theories of aging and research topics.
3. "A Decade of Discovery Yields a Shock About the Brain" - An Article about Adult Neurogenesis, The New York Times (January 4, 2000).
4. "Cognition and Aging" - Discusses How a Colony of old Macaques is Providing Clues about our Aging Brains, The Scientist (September 18, 2000).
5. "Neurogenesis in the Adult Human Hippocampus" and "Continuation of Neurogenesis in the Hippocampus of the Adult Macaque Monkey" - two recent research articles from Nature Medicine and PNAS, respectively.
6. "The Aging Process: Where Are the Drug Opportunities?" - Examines Molecular Targets for Anti-Aging Therapeutics, Current Opinion in Chemical Biology, 4:4:371-376 (2000).
7. "Aging in Peripheral Nerves: Regulation of Myelin Protein Genes by Steroid Hormones" - Considers Findings from Rats and their Potential Clinical Applications, Progress in Neurobiology, 60:3:291-308 (2000).
8. "Cognitive Aging: New Answers to Old Questions" - Highlights Discoveries from Functional Brain Imaging Studies. Current Biology, 9:R939-R941 (1999).
9. "Corticosteroids, the Aging Brain and Cognition" - Looks at the Hippocampus as a Model System for Understanding Neuronal Responses during Aging and Stress, Trends in Endocrinology and Metabolism, 10:3:92-96 (1999).
Related HMS Beagle Articles:
1. "Lessons from the Aging Brain' - a review of The 33rd Annual Winter Conference on Brain Research.
2. "Time of Our Lives" - an excerpt from Tom Kirkwood's book, Time of Our Lives: The Science of Human Aging.
3. "Our Aging Genes" - A Review of a Recent FASEB Summer Research Conference on Molecular Gerontology.