Researchers have noted that extra years of schooling during youth can reduce the risk of Alzheimer's in old age. As a group, for example, those with a college degree are less likely to develop Alzheimer's than those with only an elementary school education. But scientists are not sure why education may help ward off Alzheimer's.
Now, a large European study that looked at data spanning 20 years suggests a reason for the apparent brain-boosting benefits of formal schooling. Researchers from the U.K. and Finland looked at the brains of 872 people who had been part of three large aging studies. All had completed questionnaires about their education before they died, and their medical and cognitive histories were well known.
Confirming results of earlier studies, the researchers found that the more education someone had, the less likely they were to show the memory loss and thinking problems of Alzheimer's and other forms of dementia. For each additional year of education, the study found, there was an 11 percent decrease in risk of developing dementia.
But microscopic examination of the brains of those who had died showed an interesting finding. Many of those studied had brains that were clogged with the hallmark plaques and tangles of Alzheimer's disease. But when the scientists compared the brains of those who showed similar degrees of damage, or pathology, they found that those who were highly educated had fewer symptoms of Alzheimer's when they died than those with fewer years of schooling.
"Previous research has shown that there is not a one-to-one relationship between being diagnosed with dementia during life and changes seen in the brain at death," said study co-author Dr. Hannah Keage of the University of Cambridge in England. "One person may show lots of pathology in their brain, while another shows very little, yet both may have had dementia. Our study shows education in early life appears to enable some people to cope with a lot of changes in their brain before showing dementia symptoms."
The results are observational, so you can't draw a direct connection between staying in school and avoiding Alzheimer's in old age. People with more education tend to be wealthier than those with little education, and they may tend to live healthier lifestyles, eating healthier foods and going to the gym more often, for example. Those factors may be more important than education per se in fighting off Alzheimer's onset.
But the findings help support the theory of brain reserve, which holds that richer connections between brain cells help compensate for the degradation caused by Alzheimer's disease. Education may be one way to help build up the brain's capacity early in life. Later, as some brain cells die from the buildup of plaques and tangles of Alzheimer's, enough healthy cells remain to keep the mind and memory intact.
The theory also helps explain why many experts recommend life-long learning and stimulation to help keep the brain young. Word games and crossword puzzles, for example, may act similarly to help build up brain reserve. Read a book or learn a new language or musical instrument, the theory goes, to further stimulate and maintain the brain.
At the least, such activities will enhance your quality of life. And they may do that for years to come.
Source: Carol Brayne, et al: "Education, the brain and dementia: neuroprotection or compensation," Brain, July 26, 2010.