Older may mean happier
CLAREMONT, Calif., Jan 31, 2007 – A U.S. neuropsychologist says her research indicates senior citizens are more often happier than their children and grandchildren.
Associate Professor Stacey Wood at Scripps College in Claremont, Calif., said her study suggests older adults process negative information differently than do their younger counterparts.
In a recent experiment with collaborator Michael Kisley at the University of Colorado, both older and younger adults were shown a series of negative images (such as dead animals) or positive images (such as bowls of ice cream) and the degree to which brain activity increased was recorded. The results showed older adults are more likely to be less responsive to negative or unpleasant information.
Wood says, “In general, humans have a tendency to pay more attention to ‘bad’ than to ‘good,’ a phenomenon called the negativity bias.” Wood said. “This tendency decreases as we age.”
The study was funded by the National Institute on Aging.
Active mind may delay Alzheimer’s
New US research on mice shows that keeping an active mind may delay the development of Alzheimer’s.
The study was conducted by scientists at the University of California, Irvine (UCI).
The results are published in today’s online issue of the Journal of Neuroscience.
The study co-authors were Frank LaFerla, UCI Professor of Neurobiology and Behavior, James McGaugh, UCI Research Professor of Neurobiology and Behavior, Kim Green and Lauren Billings, both postdoctoral researchers at UCI. And it was sponsored by the US Alzheimer’s Association and the National Institutes of Health.
The researchers used hundreds of transgenic mice aged between 2 and 18 months that had been genetically bred to develop brains with plaques and tangles that are typical signs of Alzheimer’s disease.
The mice were split into two groups. In one group, the “learning group”, the mice learned to swim in a tank of water until they found a platform under the surface where they could stand. This “training” session took place four times every day for a week at age 2 and 6 months and then every 3 months until they were 18 months old. They also tested the mice’s learning and memory skills at each stage. This involved assessing how quickly they remembered the location of the submerged platform in the swimming tank.
In the other “non-learning group”, the mice just had one swimming session. Their learning and memory skills were also assessed and their brains tested for presence of plaques and tangles.
The results showed that up to the age of 12 months, the mice in the learning group had 60 per cent fewer beta amyloid plaques and tangles of hyperphosphorylated-tau in their brains, and had better learning and memory skills than the mice in the non-learning group.
However, by the time they reached 15 months of age, the brains of the mice in the learning group had degenerated to the same degree as the mice in the non-learning group, and their memory and learning ability was also the same.
Dr Green said “We were surprised this mild learning had such big effects at reducing Alzheimer’s disease pathology,” but goes on to say that the effects were not enough to stop the later and more severe decline.
The scientists are now investigating to see if more frequent and intense learning exercises have bigger and more lasting effects on slowing the decline of a brain with Alzheimer’s disease.
Professor LaFerla said “These remarkable findings suggest stimulating the mind with activities such as reading books or completing crossword puzzles may help delay and/or prevent Alzheimer’s disease in senior citizens.”
Over 4.5 million Americans have Alzheimer’s disease, which is a progressive and degenerative disorder where beta amyloid protein plaques and tangles of hyperphosphorylated-tau build up in the brain and interfere with the passing of messages between brain cells. As the population is aging, the number of people with Alzheimer’s in the US is estimated to reach 20 million by the year 2050.
5 per cent of Americans over the age of 65 have Alzheimer’s with 50 per cent of 80 year olds affected by the disease. As a cause of death Alzheimer’s ranks third behind cancer and heart disease in the US.