VOA标准英语2012--Mental Stimulation Might Cut Dementia Risk

（单词翻译）

Mental Stimulation¹ Might Cut Dementia Risk

People who engage in mentally-stimulating² activities over a lifetime have lower levels of a protein in the brain associated with Alzheimer's disease, a new study finds.
That supports other research which suggests reading, writing and playing games may lower the risk of dementia.
Researchers worked with a group of 65 older-adult volunteers with no symptoms of Alzheimer's Disease.
They answered questions about how often they engaged in stimulating mental activities throughout their lifetimes. They also got PET brain scans³ which can identify beta-amyloid deposits⁴. Those deposits are found in the brains of people who have Alzheimer's.
University of California-Berkeley scientist Susan Landau found a link between the quantity of a protein in the brain linked to Alzheimer's and the lifetime level of brain stimulation, such as reading and playing games.
"People who were the most cognitively⁶ active throughout their life, they had the least amyloid in their brains," she says. "So, based on this association between greater cognitive⁵ activity and less amyloid, we think that these people will go on to have a reduced risk of Alzheiemer's Disease."
Keep in mind that the people in this study, many of them in their 70s and 80s, did not show any symptoms of Alzheimer's. Scientists are still trying to understand the connection between beta-amyloid deposits in the brain and dementia.
Aging and a family history of Alzheimer's are both considered risk factors, but we can't control those. And even if your brain hasn't been particularly active up until now, Landau says it's not too late to start ratcheting up your mental activities.
"I think that cognitive stimulation is probably beneficial at any age. But, what our findings from this study show, is that the more cognitively active you can be over the course of your lifespan, the better"
Landau says she and her colleagues plan to follow the volunteers in this study as they age, to see whether there is a link between lifetime mental activity and Alzheimer's symptoms as some of them develop dementia in the years ahead. That may help the researchers better understand the relationship between stimulating mental activities, beta-amyloid deposits and dementia.