In recent years, many of us have come to believe that doing crossword puzzles or playing cards might ward off a decline in memory or help us maintain brainpower as we age. Now, new research suggests there might be some truth to the use-it-or-lose-it hypothesis.

In a study conducted at the Rush Alzheimer's Disease Center, and Rush-Presbyterian-St. Luke's Medical Center, scientists have found that more frequent participation in cognitively stimulating activities is associated with a reduced risk of Alzheimer's disease (AD). In fact, on a scale measuring cognitive activity, a one-point increase corresponded to a 33 percent reduction in the risk of AD.

"We are asked constantly about this use-it-or-lose-it approach to maintaining memory," said Elisabeth Koss, Ph.D., Assistant Director of the National Institute on Aging's Alzheimer's Disease Centers Program. "This study provides important new evidence that there may be something to the notion of increased cognitive activity and reduced risk of Alzheimer's disease. Further research should help better sort out whether cognitive activities can be prescribed to reduce risk of AD and why that may be so."

The research, published in the February 13, 2002 issue of the Journal of the American Medical Association, features participants enrolled in the Religious Orders Study. The Religious Orders Study is an ongoing examination of aging among older Catholic nuns, priests, and brothers from several groups across the United States.

The study followed over 700 dementia-free participants age 65 and older for an average of 4.5 years from their initial assessments. At baseline and then yearly, some 21 cognitive tests were administered to assess various aspects of memory, language, attention, and spatial ability.

At the initial evaluations, participants were asked about time typically spent in seven common activities that significantly involve information processing. These include: viewing television, listening to the radio, reading newspapers or magazines, reading books, playing games such as cards, checkers, crosswords, or other puzzles, and going to museums.

The frequency of participating in each activity was rated on a five-point scale, with the highest point assigned to participating in an activity every day, and the lowest point to engaging in an activity once a year or less.

During the follow-up period, 111 people in the study developed Alzheimer’s disease. In comparing the levels of cognitive activity with diagnosis of AD, the researchers found that the frequency of activity was related to the risk of developing the disease. For each one point increase in the participants' scores on the scale of cognitive activities, the risk of developing AD decreased by 33 percent. On average, compared with someone with the lowest activity level, the risk of disease was reduced by 47 percent among those whose frequency of activity was highest.

What accounts for the association between stimulating activities and reduced risk of cognitive decline and Alzheimer’s is unclear. Some scientists theorize that cognitive activities are protective. Others speculate that repetition might improve the efficiency of certain cognitive skills, and make them less vulnerable to the brain damage.

"The associations among cognitive activity, Alzheimer's disease, and cognitive function are extremely complex. Additional study, including testing some of these activities as cognitive interventions, will help to tell us whether such enjoyable and easy-to-do activities could be employed in some way to reduce the risk of memory decline and loss," noted Robert S. Wilson, Ph.D. and leader of the study.

Because the participants in the study have agreed to brain donation, the investigators hope to be able to determine the mechanism underlying the association between cognitive activities and cognitive decline.