Source: http://www.newyorker.com/culture/cultura...

Old age is perplexing to imagine in part because the definition of it is notoriously unstable. As people age, they tend to move the goalposts that mark out major life stages: a 2009 survey of American attitudes toward old age found that young adults (those between eighteen and twenty-nine) said that old age begins at sixty; middle-aged respondents said seventy; and those above the age of sixty-five put the threshold at seventy-four. We tend to feel younger as we get older: almost half the respondents aged fifty or more reported feeling at least ten years younger than their actual age, while a third of respondents aged sixty-five or more said that they felt up to nineteen years younger.

The researchers also found “a sizable gap between the expectations that young and middle-aged adults have about old age and the actual experiences reported by older Americans themselves.” Young and middle-aged adults anticipate the “negative benchmarks” associated with aging (such as memory loss, illness, or an end to sexual activity) at much higher levels than the old report experiencing them. However, the elderly also report experiencing fewer of the benefits that younger adults expect old age to bring (such as more time for travel, hobbies, or volunteer work).