一项新的研究表明，长时间在他们的居住场所打发时间的年长居民，更容易发展为痴呆。Cynthia Graber报道。

Keeping the brain active and engaged appears to combat the cognitive decline associated with getting older. Now a study has found a new, but related, factor in maintaining a sharp mind—the space in which we live.

Researchers recruited almost 1,300 senior citizens, none of whom showed any signs of clinical dementia at the start of the study. The participants had their cognitive function tested annually for up to eight years. And they also described their living space. For example, maybe they mostly hung around their bedroom. Perhaps they spent time in the yard. Or frequently traveled.

By the end of the study, 180 people had Alzheimers. And those whose life-space narrowed in on their immediate home were almost twice as likely to develop the condition as those who ventured out. The homebound folks also had an increased risk of other cognitive impairments and a faster rate of cognitive decline. The research was published in the American Journal of Geriatric Psychiatry.[Bryan James et al., "Life Space and Risk of Alzheimer Disease, Mild Cognitive Impairment, and Cognitive Decline in Old Age"]

The study’s lead investigator, Bryan James of the Rush University Medical Center in Chicago, suggests that, “Perhaps life space is an indicator of how much we are actively engaging and challenging our cognitive abilities.”

—Cynthia Graber