Back in September
a PSC In The News reference
"Taking Early Retirement May Retire Memory, Too" - New York Times. 10/11/2010.
Using data from the U.S., England and 11 other European countries Robert Willis and colleague Susann Rohwedder found a straight-line relationship between the percentage of people in a country who are working at age 60 to 64 and their performance on memory tests. The longer people in a country keep working, the better, as a group, they do on the tests when they are in their early 60s.