Question: Do puzzles and memory exercises really help to stave off getting Alzheimer's disease?

Answer: Using the brain by doing various "cognitive activities" like puzzles, reading newspapers and books, watching television or playing cards and board games does help stave off Alzheimer's. Research does indeed show that more frequent activity to stimulate memory and learning is associated with a slower rate of cognitive decline compared to older folks who spend little time stimulating their brain.

Another interesting way to ward off dementia, which may be too late for some, is to speak more than one language on a regular basis. In the March 30 issue of the journal Trends in Cognitive Sciences, researchers found that being bilingual can offer protection from the symptoms of dementia.

We already know that bilingualism has a beneficial effect on cognitive development in children. The researchers theorize that the need to monitor two languages in order to select the correct one recruits brain regions that are critical for general attention and cognitive control. They propose that this enhances mental flexibility in a way that the brain makes certain connections for processing information.

They also suggest that bilingualism improves "cognitive reserve," which is the protective effect that stimulating mental activity like puzzles and memory games or regular exercise has on cognitive functioning in the normal aging brain. Cognitive reserve can postpone the onset of symptoms of dementia, and this is supported by studies showing that bilingual people experience the symptoms of dementia years later than single-language people.

Mitchell Hecht specializes in internal medicine. Send questions to him at: "Ask Dr. H," Box 767787, Atlanta, Ga. 30076. Due to the large volume of mail received, personal replies are not possible.