M. Spencer Green/AP
Edith Stern, right, has lunch in the cafeteria at her retirement home in Chicago, July 30, 2013.
Scott Eisen/AP
Emily Rogalski is a neuroscientist at Northwestern University's cognitive neurology and Alzheimer's disease center in Chicago, July 29, 2013.
Rogalski is the study leader in the research of a rare group of "super agers," men and women who are in their 80s and 90s, but with brains and memories that seem far younger.
Northwestern University
A recruiting poster for Northwestern University's cognitive neurology and Alzheimer's disease center study of "super agers."
M. Spencer Green/AP
Don Tenbrunsel, 85, a soup kitchen volunteer, laughs with other volunteers as he works making lunches at St. Josaphat's Church in Chicago, Aug. 1, 2013.
Tenbrunsel is a "super ager," participating in the Northwestern University study of people in their 80s and 90s with astounding memories.
M. Spencer Green/AP
Don Tenbrunsel volunteers at a soup kitchen at St. Josaphat's Church in Chicago, Aug. 1, 2013 photo.
Scott Eisen/AP
Neuroscientist Emily Rogalski holds a human brain in the center's laboratory, July 29, 2013.
Rogalski is the study leader in the research of a rare group of "super agers."
Scott Eisen/AP
A researcher holds a human brain in a laboratory at Northwestern University's cognitive neurology and Alzheimer's disease center in Chicago, July 29, 2013.
M. Spencer Green/AP
"Super ager" Don Tenbrunsel, 85, works making lunches at St. Josaphat's Church in Chicago, Aug. 1, 2013.
M. Spencer Green/AP
"Super ager" Edith Stern, 92, works in the gift shop at her retirement home in Chicago, July 30, 2013.
M. Spencer Green/AP
Edith Stern sits in the studio apartment at her retirement home in Chicago, July 30, 2013.
M. Spencer Green/AP
Edith Stern walks through the cafeteria at her retirement home in Chicago, July 30, 2013.
M. Spencer Green/AP
Don Tenbrunsel, 85, hands out free lunches to the needy at St. Josaphat's Church in Chicago, Aug. 1, 2013.
M. Spencer Green/AP
Don Tenbrunsel, right, and Alex Wissman, soup kitchen volunteers, work at making lunches at St. Josaphat's Church in Chicago, Aug. 1, 2013.
M. Spencer Green/AP
Edith Stern, 92, talks to a new resident in the cafeteria at her retirement home in Chicago, Aug. 1, 2013.
Scott Eisen/AP
A refrigerator holding slices of human brains used for research is seen at Northwestern University's cognitive neurology and Alzheimer's disease center in Chicago, July 29, 2013.
Researchers at the university are looking at the rare group of "super agers."
M. Spencer Green/AP
Don Tenbrunsel, 85, a soup kitchen volunteer, hands out free lunches to the needy at St. Josaphat's Church in Chicago, Aug. 1, 2013.
M. Spencer Green/AP
Don Tenbrunsel a soup kitchen volunteer, laughs with other volunteers as he works making lunches at St. Josaphat's Church in Chicago, Aug. 1, 2013.