In recent years scientists have become intensely interested in what could be called a super memory club \u201d\u201d the fewer than one in 200 of us who, like Ms. Scott and Ms. Cummins, have lived past 90 without a trace of dementia. It is a group that, for the first time, is large enough to provide a glimpse into the lucid brain at the furthest reach of human life, and to help researchers tease apart what, exactly, is essential in preserving mental sharpness to the end.<\/p>\n
\u201cThese are the most successful agers on earth, and they\u2019re only just beginning to teach us what\u2019s important, in their genes, in their routines, in their lives,\u201d\u009d said Dr. Claudia Kawas, a neurologist at the University of California, Irvine. \u201cWe think, for example, that it\u2019s very important to use your brain, to keep challenging your mind, but all mental activities may not be equal. We\u2019re seeing some evidence that a social component may be crucial.\u201d\u009d<\/p>\n
Laguna Woods, a sprawling retirement community of 20,000 south of Los Angeles, is at the center of the world\u2019s largest decades-long study of health and mental acuity in the elderly. Begun by University of Southern California researchers in 1981 and called the 90+ Study, it has included more than 14,000 people aged 65 and older, and more than 1,000 aged 90 or older.<\/p>\n
Such studies can take years to bear fruit, and the results of this study are starting to alter the way scientists understand the aging brain.<\/p>\n