When talking about the psychology of success, one experiment that comes up pretty frequently is the marshmallow task. Children around 4 years old were placed in front of an edible treat of some sort, and told that if they could wait fifteen minutes without eating the treat in front of them, they would get a second treat. The children were observed and timed for how long they could go without eating the present treat, and about a third of them made it the whole fifteen minutes to the reward. The experiment was conceived to study self-control, but there have been several follow-up studies that seemed to indicate correlations between how long the children could hold out on the marshmallow task and their subsequent competence, SAT scores, and brain activity in regions related to control and addiction. In short, people often refer to the marshmallow task study to support claims that willpower at a young age predicts success later in life.
But the assumption there is that waiting is the optimal, if most difficult, strategy. Because sure, waiting for an additional reward could show self-control and the ability to look ahead, when the children think they can trust their environment. A new follow-up study explores this concept further:
While volunteering years ago at a homeless shelter for families in Santa Ana, Calif., [study author Celeste Kidd] realized that all the kids around her would eat their marshmallows straight away, living as they did in an environment where anything they had could be taken away at any time. “Delaying gratification is only the rational choice if the child believes a second marshmallow is likely to be delivered,” Kidd says.
Although previous marshmallow-type studies have acknowledged that external factors might influence kids’ ability to wait for the bigger reward, none had directly tested for those factors’ effects. So Kidd and her colleagues ran a study in which they manipulated the reliability of their young participants’ environment. A researcher gave children with an average age of four years some poor-quality art materials and told them if they could wait, she would return with better supplies. In a “reliable” condition, she did exactly that, but in an “unreliable” condition, she returned to explain she did not have any better materials after all. A marshmallow test followed. Those in the reliable condition lasted an average of 12 minutes, whereas those in the unreliable condition lasted only three.
So in fact, the marshmallow task isn’t necessarily a measure of willpower, but also a measure of environmental stability, which ties into socioeconomical status, parenting type, and many other things, and it may be these variables that are contributing to success later in life. Hopefully this message about the inherent classism of the earlier interpretations filters through to psychology popularizers as well as the scientific community.