Yet more for my reading list...

Ellen Langer is a psychology professor at Harvard. I must read this woman's books!

"In 1979, Langer and her students invited two groups of eight men in their late 70s and early 80s to go on a retreat for a week and spend time reminiscing about life 20 years earlier. "When they first showed up at the office, their daughters usually brought them," remembers Langer, who was in her early 30s at the time. "They were walking down the hall to my office, and they looked like they were just about to keel over. I remember thinking, What am I getting myself into?"

The researchers took each group of eight for a week at a time to an old monastery in Peterborough, N.H., which they had filled with props to make it look as it might have two decades before. The men watched Sgt. Bilko and The Ed Sullivan Show on a black-and-white television and listened to Rosemary Clooney and Nat King Cole on the radio. All the men (who were used to being taken care of) were encouraged to be active—for example, to help serve meals and clean up.

The first group was instructed to behave as if it really were 1959. Ahead of time, they had written autobiographical statements that stopped in that year. During the week, they spoke in the present tense as they discussed the threat of communism, the Baltimore Colts' 31-16 defeat of the New York Giants in the NFL championship game, and recently published books.

Men in the control group, which went on a separate retreat, followed a similar program but were permitted to speak of the past as the past. They spent time reflecting on their younger days, while the first group in effect tried to take themselves back in time.

What happened? After just one week, both groups tested better on hearing and memory. The men gained an average of three pounds each, and their grips were stronger. "At the end of all this, I was playing touch football with some of them," says Langer.

But the changes were especially striking in the first group: Their joints became more flexible and their hands more nimble. Sixty-three percent of them improved on intelligence tests, compared with 44 percent of the control group. And people unaware of the purpose of the study rated every member of the first group younger in photos taken after the retreat than in photos taken before.

"When I first described the study, I was hesitant to spell out just how big the changes were," says Langer, who wrote about it in her 1989 book, Mindfulness (Addison-Wesley), but did not publish the study in a psychology journal. In a field experiment like this one, lacking the controls of the lab, many factors might have explained the results.

"The most important part of the study," she says, "was that people who are only supposed to get more debilitated over time showed great improvement—regardless of the reason."

More here.