Willpower alone doesn’t explain why some children forgo a marshmallow in hand for the prospect of getting two gooey treats later. Kids’ beliefs about the reliability of the people around them, such as the trustworthiness of an experimenter, can dramatically shape their willingness to wait for a sweeter payoff, a new study finds.
Expectations about whether it’s best to grab goodies before they disappear or trust that bigger returns will come later are as important to delaying gratification as self-control, say psychologist Celeste Kidd of the University of Rochester in New York and her colleagues. If so, preschoolers’ family backgrounds may partly explain why young children able to wait for more treats adjust particularly well as teenagers (SN: 5/27/89, p. 325).
Children from stable families may reasonably assume that it’s worth it to wait for more treats in a lab task, Kidd proposes. Those kids are also more likely to succeed socially and academically later in life.
Her team’s findings appear in a paper published online Oct. 9 in Cognition.
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“Our data suggest that it is premature to conclude that a child’s capacity for willpower is what determines his or her future success,” Kidd says. “Beliefs about the reliability of others’ behavior inform children’s decisions about whether to wait for a better reward.”
Kidd’s team modified a procedure, called the marshmallow task, that was developed by psychologist Walter Mischel, now of Columbia University, in 1972. An experimenter would lead preschoolers to a room where they could eat a marshmallow, cookie or pretzel placed on a table or wait 15 minutes to get two treats. Children lasted an average of about six minutes before munching a treat in hand. When Mischel followed up with the kids years later, he found that the longer kids had managed to wait, the better they did socially and academically as teens.
In the new experiment, Kidd’s group tested 28 youngsters, ages 3 to 5, on the marshmallow task. Before testing, the children completed an art project. Half dealt with an unreliable experimenter who failed to deliver on promises to bring back fancy art supplies and cool stickers. The rest had a reliable experimenter, who provided art supplies and stickers as promised.
Children who had been disappointed by an experimenter waited for an average of about three minutes before eating the marshmallow, while those who got what was promised lasted 12 minutes. After an unreliable encounter, only one of 14 kids waited the full 15 minutes for the second marshmallow, compared with nine of 14 kids assigned to a reliable experimenter.
Findings consistent with Kidd’s study go back 50 years, Mischel says. In 1961, for instance, Mischel reported a preference for immediate rewards among 8- to 9-year-old boys without a father in the home, relative to boys with a mother and a father.
“Kidd’s finding makes good sense, but it’s not surprising,” Mischel says.
Researchers have not previously shown that manipulating young children’s beliefs about adults’ trustworthiness can shorten or extend wait times on the marshmallow task, Kidd responds. That’s a clear sign that the task invokes worldviews, not just self-control, she says.
No word yet on whether the marshmallow task can explain why some trick-or-treaters save their candy for weeks and others come home with stuffed bellies and empty bags.