Older may mean wiser, but it also means declines in rational decision-making abilities, according to a new study from the Yale School of Medicine.
The researchers found that adults between the ages of 65 and 90 were more risk-averse than younger adults when it came to choosing between two possible gains, but more risk-seeking when choosing between losses. The elderly also showed less choice consistency than younger adults. The findings suggest these unique decision-making abilities should be considered in helping the elderly make choices in domains from health care policy to finance, study senior author and professor of comparative biology Ifat Levy said.
“What we show in this study is that age matters a lot in decision-making,” she said. “These age-related patterns should really be taken into account when policy makers are deciding on policies.”
To analyze how the decision-making function changes across the life span, the researchers recruited 135 healthy subjects between the ages of 12 and 90 and had them make 320 choices between monetary gains and losses. In the gain trials, subjects decided between a sure gain of $5 and a lottery of varying monetary gain, while in the loss trials, subjects chose between a loss of $5 or a corresponding risky lottery. To test for whether subjects were consistent in their choices, researchers also repeated each of the trials four times.
The results showed that in gain trials, the elderly were more risk-averse than their midlife counterparts, but in the loss trials, elders were more risk-seeking — willing to gamble for the possibility of losing less money than taking a loss for certain. Levy and colleagues also found that older adults were significantly less consistent than younger adults, as they provided different answers to identical questions.
Levy said that the difference in risk-taking between older and younger adults may stem from a transitioning outlook on life: The elderly are more willing to take a sure gain because they are satisfied with their lives, while they are happy to gamble to avoid losses because they are optimistic that the lottery will yield a favorable result.
Director of Cornell University’s Human Neuroscience Institute Valerie Reyna offered an alternative explanation for the dissimilar risk preferences between older and younger adults. Reyna conducted a study where she found that experts in risky decision-making, such as intelligence agents, show the same decision biases that Levy noticed in the elderly. Specifically, as compared to college students, the experts are more risk-averse when choosing between gains, but more risk-seeking when choosing between losses.
“Older adults, like experts in risky decision-making, have more experience in making decisions,” she said. “This experience actually seems to increase rather than decrease the bias.”
Levy’s study shows that the elderly rely on emotional rather than computational reactions to risks when making decisions, a bias that has implications for helping the elderly make better financial choices, said Yale School of Management professor of marketing Nathan Novemsky.
Levy said that this study was done in preparation for an fMRI study that will show which brain areas are involved in decision-making and how brain activation changes with age.
The study, which was supported by the National Institute of Aging, appeared in the Sept. 30 edition of the Proceedings of the National Academy of Sciences.