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Researchers who study Alzheimer's disease released a new study of seniors in Chicago this week. It confirms what we've been hearing for a while: keeping an active mind does help protect against the onset of dementia. But it turns out that the use it or lose it strategy only works for so long. As NPR's Allison Aubrey reports, once mental decline sets in, it's the folks who've been most cognitively engaged who decline the fastest.
ALLISON AUBREY: Researchers recruited a whole neighborhood of folks age 65 and older from one area of Chicago, about 1,100 in all. And when the study began 12 years ago, they were all free of dementia.
Robert Wilson, a professor of neurological sciences at Rush University, led the study. He says at the outset they asked each senior how often they participated in stimulating activities such as...
Dr. ROBERT WILSON (Rush University): Reading a newspaper, listening to the radio, going to a museum, playing board games like chess or checkers.
AUBREY: And lots of other activities. Then they gave each person a score. The more frequently people engaged in stimulating activities, the higher the score.
More than a decade later, they followed up with cognitive evaluations and diagnostic exams. What they found is that the people who had developed Alzheimer's and had also started out with high scores for their mentally stimulating lifestyles were the very individuals who were declining fastest.
Dr. YAAKOV STERN (Columbia University): Even someone who's brilliant and engages in a lot of activities, they might reduce their risk of developing Alzheimer's disease for a while, but the disease really does win in the end.
AUBREY: Yaakov Stern is professor of clinical neuropsychology at Columbia University.�He says these findings fit with what researchers have theorized for a while now - mentally engaged people build up what he calls a cognitive reserve that may help them compensate when the initial damage of Alzheimer's -including a buildup of plaques and tangles in the brain - start to develop. But he says it's not exactly clear how this works.
Dr. STERN: One simple idea is that perhaps they have more flexibility in how they approach tasks. So they can - if the pathology begins to affect one aspect of the networks in the brain, they might be able to use alternate networks to solve the problem or do the task.
AUBREY: So for those who are mentally engaged, it may take many more years for the symptoms of the disease to appear. But once they do, the course of the disease seems to speed up. Robert Wilson says there's a bit of a silver lining knowing that the disease will likely progress more quickly.
Dr. WILSON: So we think this is really good news. It suggests that cognitive activity extends your period of independence as long as it possibly can.
AUBREY: While at the same time, Wilson says, shortening the battle at the end of life and making patients less of a burden to caregivers and their loved ones.
Allison Aubrey, NPR News.