In this Aug. 1, 2013 photo, 85-year-old Don Tenbrunsel, right, and Alex Wissman, soup kitchen volunteers, work at making lunches at St. Josaphat's Church in Chicago. Tenbrunsel is a "super ager," participating in a Northwestern University study of people in their 80s and 90s with astounding memories. So far the research has found scientific evidence that brains in this elite group resemble those of people decades younger. (AP Photo/M. Spencer Green)

They're called "super agers"—men and women who are in their 80s and 90s, but with brains and memories that seem far younger.

Researchers at Northwestern University are looking at this rare group in the hope that they may find ways to help protect others from . And they've had some tantalizing findings: Imaging tests have found unusually low amounts of age-related plaques along with more brain mass related to attention and memory in these elite seniors.

The super agers aren't just different on the inside; they have more energy than most people their age and share a positive, inquisitive outlook. Researchers are looking into whether those traits contribute to .

The study is still seeking volunteers, but fewer than 10 percent of would-be participants are eligible.

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