This is the title of an article by Benedict Carey in last Tuesday's NYTimes science section (7/18/06) pointing to work reported in the current issue of the journal Social Cognition. Men and women in late middle age (48-62) underperformed on a standard memory test when told they were part of a study including people over age 70. Inclusion with an older group — an indirect reminder of the link between age and memory slippage — was enough to affect their scores, especially for those who were most concerned about getting older. Scores were higher when participants were told they were competing with a group in their 20's. The findings “show how negative images of aging on TV, in other media and in jokes reinforce negative stereotypes that can affect performance even before people reach retirement age."
This self-undermining is a stereotype effect, of the sort that has been documented it in many groups. Other studies have shown that women perform less well on math exams after reading that men tend to perform better on them. Similarly, white men perform less well when they are told that they are competing in math against Asian students.