UI research shows older people recognize errors less often than
younger people
BY RICHARD C.
LEWIS
In a new study, University of Iowa researchers devised a simple,
computerized test to gauge how readily young adults and older adults realize
when they’ve made a mistake.
Older adults performed just as well as younger adults in tests
involving looking away from an object appearing on the screen.
But younger adults acknowledged more often than older adults when they failed to look away from the object. And, older adults were more likely to be adamant that they did not made a mistake.
But younger adults acknowledged more often than older adults when they failed to look away from the object. And, older adults were more likely to be adamant that they did not made a mistake.
“The good news is older adults perform the tasks we assigned them just as well as younger adults, albeit more slowly,” says Jan Wessel, assistant professor in the UI Department of Psychological and Brain Sciences and the study’s corresponding author. “But we find there is this impaired ability in older adults to recognize an error when they’ve made one.”
The research offers new insight how older people perceive their
decisions, and especially how they view their performance—whether judging their
own ability to drive or how regularly they believe they’ve
taken medications.
“Realizing fewer errors can have more severe consequences,” Wessel
says, “because you can’t remedy an error that you don’t realize
you’ve committed.”
Wessel’s team recruited 38 younger adults (average age of 22) and
39 older adults (average age of 68) to take a series of tests that involved
looking away from a circle appearing in a box on one side of a computer screen.
While the test was simple, younger adults couldn’t resist glancing at the circle before shifting their gaze about 20 percent of the time on average. That’s expected, Wessel says, as it’s human nature to focus on something new or unexpected, and the researchers wanted the participants to err.
While the test was simple, younger adults couldn’t resist glancing at the circle before shifting their gaze about 20 percent of the time on average. That’s expected, Wessel says, as it’s human nature to focus on something new or unexpected, and the researchers wanted the participants to err.
After each failed instance, the participants were asked whether
they had made an error. They then were asked “how sure” and used a sliding
scale from “unsure” to “very sure” to determine how confident they were about
whether they had made a mistake in the test.
The younger participants were correct in acknowledging when they
had erred 75 percent of the time. The older test-takers were correct 63 percent
of the time when asked whether they had erred. That means in more than
one-third of instances, the older participants didn’t realize they had made
a mistake.
Even more, the younger participants who made an error on the test
were far less certain than the older participants that they were correct. In
other words, the younger adults hedged more.
“It shows when the younger adults thought they were correct, but
in fact had made an error, they still had some inkling that they might have
erred,” says Wessel, who is affiliated with the Department of
Neurology and the Iowa
Neuroscience Institute. “The older adults often have no idea at all
that they were wrong.”
The researchers underscored these observations by measuring how
much participants’ pupils dilated as they took the tests. In humans and most
animals, pupils dilate when something unexpected occurs—triggered by surprise,
fright, and other core emotions. It also happens when people think they’ve
blundered, which is why researchers measured pupils in the experiments.
Researchers found younger adults’ pupils dilated when they thought
they erred. This effect was reduced when they committed errors they did not
recognize. In comparison, older adults showed a strong reduction of this pupil
dilation after errors that they recognized and showed no dilation at all when
they committed an error they did not recognize.
“That mirrors what we see in the behavioral observations,” Wessel
says, “that more often they don’t know when they’ve made an error.”
The paper, “A blunted phasic autonomic response to errors indexes
age-related deficits in error awareness,” was published online on June 28 in
the journal Neurobiology of Aging.
Contributing authors at the UI include Andrew Hollingworth,
professor in the Department of Psychological and Brain Sciences, and Kylie
Dolan, an undergraduate psychology major.
The Aging Mind and Brain Initiative at the UI and the Roy J. Carver
Foundation funded the research. Dolan received support from the UI’s Iowa
Center for Research by Undergraduates.