Cognitive Activities Necessary to Protect Against Alzheimer’s Disease — Social and Physical Activities Not Enough
Research at The Byrd Alzheimer’s Institute Shows Cognitive Activity as You Age is the Best Way to Protect Against Memory Loss
08.30.07
TAMPA - So you want to protect your brain against Alzheimer’s disease, but are not sure what daily activities are best — social activities? Physical exercise? Mental activities? New research now shows for the first time that, of all lifelong activities, only a high level of mental or cognitive activity protects against the devastating memory loss of Alzheimer’s disease. High levels of social and/or physical activity are not enough to reduce risk of AD.
Although social or physical activity have both been reported to protect against AD in earlier human studies, it is impossible to separate these activities from cognitive activities in humans. Moreover, it is impractical to do scientifically-controlled human studies and to do such studies over many decades. However, highly controlled studies separating social, physical, and cognitive activities during aging can be done in Alzheimer’s mice that develop the memory impairment and brain pathology of the disease.
That’s exactly what the Byrd Institute researchers did. They raised Alzheimer’s mice from young adulthood through older age in one of four housing environments — high social activity, high physical activity, high cognitive activity, or a single-housing control environment. When the researchers tested the Alzheimer’s mice in a battery of memory tasks in older age, only the Alzheimer’s mice given a lifelong high level of cognitive activity were protected against memory impairment. In fact, these “high cognitive activity” mice performed as well as normal mice that do not develop Alzheimer’s disease. In sharp contrast, the Alzheimer’s mice raised in one of the other three environments performed poorly in multiple memory tasks.
Not only was memory protected in Alzheimer’s mice by a high level of cognitive activity, but brain levels of the abnormal protein beta-amyloid were substantially reduced only by a high level of cognitive activity. This protein, thought to be key for Alzheimer’s development, remained at soaring levels in the brains of Alzheimer’s mice raised in social or physical activity environments. Moreover, the researchers found that only the Alzheimer’s mice raised with high cognitive activity had an increase in connections between brain cells. Alzheimer’s mice raised in one of the other three housing environments had much fewer connections between their brain cells.
Earlier studies in humans reported that social and physical activities are important in protecting against the very mild loss of memory that most people get during aging. However, Dr. Gary Arendash, the lead researcher on the study, cautions that this mild age-related memory impairment is not the same as the devastating memory loss of Alzheimer’s disease. The new study, published in the Neurobiology of Learning and Memory Journal, done in Alzheimer’s mice, is directly relevant to Alzheimer’s memory loss in concluding that cognitive activity is much more important than social or physical activity for protecting against or delaying Alzheimer’s disease. “Our results call into question the earlier human studies suggesting social or physical activity provides protection against Alzheimer’s,” said Dr. Arendash.
“Alzheimer’s begins in the brain several decades before any symptoms show up,” said Dr. Arendash. “That means adults in their forties and fifties need to make lifestyle choices now to decrease their risk of getting Alzheimer’s disease later.” These choices include not only maintaining a high level of cognitive activity, but also having a diet high in fruits and vegetables but low in saturated fats, as well as keeping your blood pressure and cholesterol levels in check. “By the time you’re in your sixties, many people already have developed appreciable Alzheimer’s pathology in their brains,” said Dr. Arendash. Indeed, genetic cases of the disease can begin in the late 20’s. All the more reason to emphasize cognitive activity throughout life, Dr. Arendash emphasized.
So for all the crossword and Sudoku lover’s out there, all the hours spent trying to solve those addicting puzzles could be critical for protecting against or delaying Alzeimer’s disease. Don’t just stop at those challenging word puzzles though. They are a start, but staying cognitively active in the workplace, limiting time spent watching TV, and continually challenging your brain throughout life are all helpful ways to reduce the chances of developing Alzheimer’s disease. Dr. Arendash also suggests activities such as reading, playing cards or having intellectually stimulating conversations.
Recently, several computer game manufacturers have marketed brain exercise programs to stimulate cognitive function. These brain games, such as Nintendo’s new “Brain Age 2” may be a good way to keep your mind sharp during aging, although their ability to provide benefits over and above the benefits provided by leading a cognitively active life-style remain to be proven.
“Our findings once again emphasize the concept that lifestyle choices you make in middle age can directly impact your chances of getting Alzheimer’s disease,” said Dr. Arendash. Although there are currently no effective therapeutics available to slow Alzheimer’s development, Dr. Arendash and his colleagues are encouraged by the steady increase in therapeutic development. Based on promising work in Alzheimer’s mice, for example, the Byrd Alzheimer’s Institute has begun clinical trials to determine if caffeine can reduce blood levels of beta-amyloid in aged individuals. Several vaccines are also under development at the Byrd Institute, as well as a variety of naturally-occurring compounds that could provide a safe and effective treatment for the disease.
Alzheimer’s is a neurodegenerative disease that results in the loss of brain cells and their connections. It affects more than 4 million Americans and costs the U.S. economy $100 billion a year. Ten percent of people age 65 and older and half of those age 85 and older are victims of the disease — largely because people are living longer than ever before.
The Byrd Alzheimer’s Institute is continually devoted to the fight against Alzheimer’s disease. It will be opening its doors to a brand new, state-of-the-art research facility on Saturday, September 15, 2007 on the University of South Florida’s campus. The 7-story building, with over 100,000 square feet will be the largest free-standing research facility dedicated to Alzheimer’s research in the world.
Community members are invited to see what this revolutionary Institute has to offer. A hands-on interactive tour will give the public a firsthand look at the behind the scenes work of the dedicated scientists at the Byrd Institute. Refreshments and prizes are included in the public’s first opportunity to see the new building. To RSVP or for more information contact Kelleigh Klein at 813.319.4126 or kklein@byrdinstitute.org
The mission of the Byrd Alzheimer’s Institute is to prevent and cure Alzheimer’s disease. Created in 2002 by the Florida Legislature, the Institute is dedicated to supporting and coordinating the tremendous research, expertise, and creative vision of scientific professionals all over Florida.
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