February 17, 2011
Mentally stimulating activities like doing crossword puzzles, reading and visiting museums may slow the decline of thinking skills with advancing age and delay the onset of Alzheimer’s disease and other forms of dementia, according to a new report. But the benefits may not be permanent. Once Alzheimer’s is diagnosed, the course of the disease may be more rapid in those who were more mentally active. The findings appeared in Neurology, the medical journal of the American Academy of Neurology.
“Our results suggest that the benefit of delaying the initial signs of cognitive decline may come at the cost of more rapid dementia progression later on,” said study author Robert S. Wilson of Rush University Medical Center in Chicago.
Researchers are not sure why doing crossword puzzles and other challenging tasks may delay the symptoms of Alzheimer’s. One theory is that mentally stimulating activities enhance the brain’s circuitry, enriching communication between brain cells involved in thinking and memory. Despite the accumulation of the plaques and tangles that can damage the brain and lead to Alzheimer’s, enough healthy brain connections might remain to keep the brain working normally.
But once memory loss has become severe and a diagnosis of Alzheimer’s is made, those who engaged in active mental activities and learning may tend to have accumulated more damage to brain cells (without showing symptoms) than those who were less mentally challenged. Therefore, those who stayed mentally active also tended to deteriorate more rapidly than their less mentally challenged peers, once increased brain reserve was overwhelmed by the disease.
Dr. Wilson noted that mental activities compress the time period that a person spends with dementia, delaying its start and then speeding up its progress. “This reduces the overall amount of time that a person may suffer from dementia,” he said.
For the study, researchers evaluated the mental activities of 1,157 people ages 65 and over, gauging their participation in activities like listening to the radio, playing games and doing crossword puzzles, watching television, reading and going to a museum. None had Alzheimer’s or other forms of dementia at the start of the nearly 12-year study.
During the next six years, they were also given memory and thinking tests to look for signs of Alzheimer’s. The researchers found that the more activities someone engaged in, the slower their rate of mental decline. But for those with Alzheimer’s disease, the more they engaged in mentally challenging activities, the faster their rate of cognitive decline once they got Alzheimer’s.
The researchers note that engaging seniors in mentally stimulating activities may prove beneficial in delaying onset of Alzheimer’s. They cite earlier studies showing that challenging pursuits like taking acting classes or working in an elementary school may be particularly promising for helping to keep the mind sharp in old age. The current findings add a further voice to the call for keeping the mind sharp, suggesting that while mental stimulation cannot prevent Alzheimer’s altogether, it may at least compress the course of the disease.
Source: R.S. Wilson, PhD; L.L. Barnes, PhD; N.T. Aggarwal, MD, et al: “Cognitive Activity and the Cognitive Morbidity of Alzheimer Disease.” Neurology, Sept. 1, 2010.