Older individuals who are subliminally exposed to positive stereotypes about aging showed improved physical functioning that can last for several weeks, a new study led by the Yale School of Public Health has found.

Researchers used a novel intervention method to examine for the first time whether exposure to positive age stereotypes could weaken negative age stereotypes and their effects over time, and lead to healthier outcomes.

The study, to be published online in an upcoming issue of the journal Psychological Science, consisted of 100 older individuals (average age 81 years) who live in the greater New Haven, Connecticut area. Some of the participants were subjected to positive age stereotypes on a computer screen that flashed words such as "spry" and "creative" at speeds that were too fast to allow for conscious awareness.

Individuals exposed to the positive messaging exhibited a range of psychological and physical improvements that were not found in control subjects. They benefited from improved physical function, such as physical balance, which continued for three weeks after the intervention ended. Also, during the same period, positive age stereotypes and positive self-perceptions of aging were strengthened, and negative age stereotypes and negative self-perceptions of aging were weakened.

"The challenge we had in this study was to enable the participants to overcome the negative age stereotypes which they acquire from society, as in everyday conversations and television comedies," said lead researcher Becca Levy, associate professor and director of the Social and Behavioral Science Division. "The study's successful outcome suggests the potential of directing subliminal processes toward the enhancement of physical function."

While it has been previously shown by Levy that negative age stereotypes can weaken an older individual's physical functioning, this is the first time that subliminal activation of positive age stereotypes was found to improve outcomes over time.

The study found that the intervention influenced physical function through a cascade of positive effects: It first strengthened the subjects' positive age stereotypes, which then strengthened their positive self-perceptions, which then improved their physical function.

The study's effect on physical function surpassed a previous study by others that involved a six-month-exercise intervention's effect with participants of similar ages.