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Hi All; It's the media hound again. I think it's interesting that this has been released to the news media, prior to the medical journal publication. (Neurology) And I think Mischa Frankel has just made it onto my hero list. Janet ---------------------------------------------------------------------- Studies suggest older minds stronger than expected ---------------------------------------------------------------------- Copyright ) 1996 Nando.net Copyright ) 1996 N.Y. Times News Service (Feb 25, 1996 10:27 p.m. EST) The conventional image of the aging brain is that people lose neurons the way balding men lose hair. Brain cells are supposed to start falling away around the age of 20, with everything downhill from there. Some people go bald, or senile, early. Some lucky and unusual ones keep their hair, or their wits, about them into their 90s and beyond. Science has precious little good news about hair loss, but new findings on the death of brain cells suggest that minoxidil for the mind is unnecessary. Data from men and women who continue to flourish into their 80s and 90s show that in a healthy brain, any loss of brain cells is relatively modest and largely confined to specific areas, leaving others robust. In fact, about 1 of every 10 people continue to increase in mental abilities like vocabulary through those decades. New imaging techniques, like the PET scan and magnetic resonance imaging, or MRI, have shown that the brain does gradually shrink in life's later decades, just not as much as had been thought. Furthermore, the shrinkage of a healthy brain does not seem to result in any great loss of mental ability. "We used to think that you lost brain cells every day of your life everywhere in the brain," said Dr. Marilyn Albert, a psychologist at Massachusetts General Hospital in Boston. "That's just not so -- you do have some loss with healthy aging, but not so dramatic, and in very selective brain areas." The new imaging techniques have also enabled neuroscientists to discover a flaw in many earlier studies of the aging brain: they included findings from people in the early stages of Alzheimer's disease. Now, both by scanning the brain and by more carefully screening to measure cognitive function, most people with Alzheimer's are excluded from such studies. Researchers measure brain shrinkage by keeping track of the fjord-like spaces that crease the wrinkled surface layer of the cerebral cortex, the topmost layer that is critical for thought. These tiny crevasses are called ventricles and sulci, and the amount of space in them gradually increases with age, reflecting a loss in the overall mass of the brain. From age 20 to 70, the average brain loses about 10 percent of its mass, said Dr. Stanley Rapoport, chief of the neuroscience laboratory at the National Institute on Aging in Bethesda, Md. But that loss "seems related only to subtle differences in cognitive abilities," Rapoport said. "We think the brain's integrity is maintained because the massive redundancy of interconnection among neurons means that even if you lose some, the brain can often compensate." Compensation is precisely what studies of the "successful" elderly show. When neuroscientists weed out people with cognitive decline that is a sure sign of illness, the shrinkage is still there, but performance on mental tests is good. And what analyses of healthy old brains show is that old people may use different parts of the brain from young people to accomplish the same task. In some ways a healthy old brain is like a pitcher whose fastball has faded but who can still strike a batter out with other pitches. Some of the data come from autopsies of 25 men and women from 71 to 95 years old who had volunteered to be part of a control group in a 16-year study of Alzheimer's disease. Dr. John Morris, a neurologist at Washington University in St. Louis who did the study, said the brains of the mentally alert group showed some of the tangles that, more than shrinkage, seem to be the main problem in Alzheimer's disease. But these tangles were in the hippocampus, a structure involved in memory, rather than the centrally important cerebral cortex. Morris said his data, which will be published next month in the journal Neurology, suggest "there may be a pool of people who not only have no important cognitive declines, but no brain changes of consequence for mental function, even into their 80s and 90s." Changes in the hippocampus may only slow the rate of retrieval from memory, he said, but not diminish its accuracy. Similar findings have been made by Dr. Brad Hyman of Massachusetts General Hospital. "We've found no appreciable neuronal loss in people from their 60s to 90s who had retained their mental clarity until they died," said Hyman, who studied two specific regions of the cortex. "The dire picture we've had of huge cell losses is wrong for a healthy person whose brain remains structurally intact into old age." Apart from a reduction in the number of brain cells, another aspect of aging in the healthy brain seems to be a drop in the connections between them. Dr. Albert at Massachusetts General said her studies of brain tissue had uncovered specific structures deep in the brain that did show more neuronal loss, even with healthy aging. These include areas important for memory like the basal forebrain. But, Dr. Albert said, "It's important for mental abilities that most of the neurons in the cortex are retained -- they store information once you've learned it." Some of the most intriguing evidence for the resourcefulness of the aging brain comes from PET scans of the brain at rest and while engaged in mental tasks. In one study using PET scans that compared people in their 20s with those 60 to 75, Dr. Cheryl L. Grady, a neuroscientist at the National Institute on Aging, found that the younger people were indeed quicker and more accurate in recognizing faces, and used more diverse areas of their brains during the task, than did the older people. But in similar studies at the institute comparing people from 20 to 40 with those 55 and older, the older group was able to recognize the faces with about the same accuracy, though they needed more time to do so than the younger group, Rapoport said. Images of the brains of the older group showed less activity in visual areas of the brain, but more activity in the prefrontal cortex, suggesting increased mental effort. Rapoport said that in older people there seemed to be some loss of circuits involved in visual memory. "So the brain has to recruit other circuits to get the task done," he said. But recruit it does. The prefrontal cortex, which is the brain's executive area for intellectual activity, appears especially crucial in compensating for areas that no longer function so well in mental tasks. All is not rosy. The number of people who do end up with Alzheimer's disease and fall into senility is still quite large. "There are three very different groups among the elderly," said Dr. Guy McKhann, director of the Zanville and Krieger Mind Brain Institute at the Johns Hopkins Medical School. "One does remarkably well, aging very successfully into their 80s and 90s. The second group slides a bit, having some problems with memory and recall, but the problems are typically more aggravating than they are real." McKhann said that the third group, which largely consists of people with Alzheimer's disease, suffers inexorable losses in mental function leading to senility. That group accounts for about 15 percent of those in their 70s and 30 percent to 40 percent of those in their 80s. But for those without disease, the brain can withstand aging remarkably well. "Some people stay very good at intellectual tasks all their lives, " said Dr. Judith Saxton, a neuropsychologist at the University of Pittsburgh Medical Center, who is analyzing data from a two-year follow-up of more than 700 men and women from 65 to 92. "Their overall knowledge and vocabulary continues to grow as they age, even though their speed of retrieval slows a bit." Saxton added. "I'd guess up to 10 percent of people above 70 fall in this range." The question that interests many people who are headed toward 70, as well as some new and unconventional researchers, is how and why one ends up in this 10 percent. Is a person's neurological fate predetermined? Or is there something that can be done to stay healthy and mentally alert? Dr. James I. McKinney With a Ph.D. from Yale University, Dr. James I. McKinney, 89, has lived a life of the mind, teaching philosophy at universities and writing books. His home is in Baltimore, where he is a visiting professor at Morgan State University, teaching a course in Christianity. He just finished writing a biography of Mordecai Wyatt Johnson, who was president of Howard University. McKinney said he thought the infirmities of old age were often exaggerated by people who see an elderly person and assume that he or she is feeble, if not senile. "I was on a plane a few days ago and a man wanted to help me get my luggage off the rack," McKinney said. "He assumed that I would not be able to." Despite its popular image, he said, old age, for him, is hardly a dreary time. "I think part of my good fortune is that I have stayed around young people," McKinney said. "When I stay around young people, I don't realize how old I am." Mischa Frankel Mischa Frankel celebrated his 84th birthday on Feb. 1 in the Virgin Islands, attending a seminar at the Omega Institute, dancing to African drumming and leading a group in an old folk song with the refrain, "Love is something that if you give it away, you end up having more." That might well be his credo; for the last half century Frankel has dedicated himself to working with the elderly, leading them in folk dances and folk songs of his native Russia and other countries. For 25 years, beginning in 1951, Frankel worked his magic at the Henry Street Settlement House on Manhattan's Lower East Side; the social work agency's eminent director, Helen Hall, wrote of his work there, "He could make a zombie sing and dance." For the last 26 years Frankel has worked with Alzheimer's patients in wheelchairs at Menorah House in Brooklyn, walking the half hour there and back from his home in Sheepshead Bay. Frankel credits his vitality to having been a fitness buff most of his life, an avid jogger, walker and dancer. ---------------------------------------------------------------------- Janet Paterson - 48 - 7 - [log in to unmask] - Bermuda