(HealthDay News) -- Reading, crossword puzzles and other mentally stimulating activities have pros and cons when it comes to Alzheimer's disease, new research suggests.

In line with prior research, the study finds that such mental activity may slow declines in thinking and memory during normal old age.

But folks who loved these pursuits actually displayed a hastening of their mental decline once symptoms of dementia began to set in, the researchers say.

"We think there's a trade-off," said senior study author Robert Wilson of Rush University Medical Center in Chicago. Keeping mentally active means that there is "a little more time during which the person is cognitively competent and independent and a little less time in a disabled and dependent state" once dementia does set in, said Wilson, who is senior neuropsychologist at Rush's Alzheimer's Disease Center.

The findings were published online Sept. 1 in Neurology.

Previous work has suggested that engaging in cognitively challenging activities may help ward off the appearance of dementia in older people. To test this, Wilson and his co-workers tracked almost 1,200 older individuals over nearly 12 years. Read more...

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