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Marshmallows, Willpower, and Reliability

"Eat the marshmallow" is a rational strategy in unreliable situations.

Go ahead! Eat that marshmallow!

Have you ever judged someone harshly for not having enough willpower? Try as I might to be compassionate, I’ve made those snap judgments, too. But I’ll think twice—or three times—before I do it again, now that I’ve read the latest research on how reliability and willpower are linked.

The latest study is a variation on psychologist Walter Mischel’s famous marshmallow studies, published in 1972, showing that young children differ greatly in their self-control ability In these studies, Mischel and associates put hundreds of preschoolers in a room, one at a time, with a marshmallow on the table. A researcher explained to each child that he/she could eat the marshmallow now or wait until the researcher returned to the room and get two marshmallows.

Mischel’s team then followed the children through high school. The “delayers”—the kids with good self-control as children—were less likely to have substance abuse problems, got along better with their peers, and had higher SAT scores. The “grabbers,” who gobbled their marshmallow within seconds or minutes of the researcher’s absence, often had behavioral problems and did poorly in school. Some people used these studies to argue that good self-control was an innate trait.

I always found these results alarming and disheartening. A child’s willpower at age four could predict his or her future success? Mischel may have felt the same way because he later developed a series of experiments designed to see whether stronger willpower could be taught. (Short answer: Yes, it could.)

In the recent version of the marshmallow experiments, cognitive scientists Celeste Kidd, Holly Palmeri, and Richard Aslin explored whether willpower could be affected by what is normally an invisible force—the reliability of the researcher doing the experiment. They assigned 28 children, aged three to five, to one of two conditions: the reliable condition and the unreliable condition.

All children were told they would be given the opportunity to decorate a cup with a paper insert. In all cases, each child sat at a table with a Mason jar of used crayons. In the unreliable condition, the researcher told the children that if they could wait, the researcher would bring in a tray of new art supplies. However, after a few minutes, the researcher returned empty-handed, saying, "I'm sorry, but I made a mistake. We don't have any other art supplies after all.” The researcher also offered to supply the child with stickers and reneged on that promise as well.

In the reliable condition, the researcher returned as promised, first with an attractive tray of art supplies, then with a set of large stickers.

Then the marshmallow challenge was explained: One marshmallow now or two if you can wait.

Children with the reliable experimenter were able to wait an average of 12 minutes, with nine holding out for the full 15 minutes. Children in the unreliable condition, by contrast, could only wait an average of three minutes, with only one child resisting for the entire 15 minutes. So children in the reliable condition held out four times longer than those in the unreliable condition—an “astonishing” difference, according to one researcher.

The study's authors described the "grabber" choice as a rational response, since those kids had learned the lesson that the researcher might not return with the promised goodies. As the tongue-in-cheek headline in Mother Jones proclaimed, “Delayed Gratification Not a Winning Strategy if Researchers are Big Meanies.” (Hey! Researchers! How about sending a tray of art supplies, stickers, and a note of apology to children in the unreliable condition?)

This experiment, though small, shows the amazing power of other people to shape our willpower, for better or for worse. By coincidence, I’ve been reading the book Situations Matter by Sam Sommers. Sommers argues that when we try to explain human behavior, we tend to overestimate the power of personality and underestimate the power of situations—the context we find ourselves in. The people you are with and how they treat you can have a profound impact on your self-control.

Think of children who live in chaotic, violent, or disorganized environments with parents who, for one reason or another (poverty, mental illness, alcoholism/addiction, lack of skill), cannot provide the basic stability and predictability that is reassuring to most children and that allows them to anticipate and plan for a good future. For these children, it is rational to “eat the marshmallow,” so to speak, rather than wait for a better reward that might never come.

My tentative conclusion: If you want to increase your willpower, consider bringing more trustworthy people into your life. A reliable, predictable environment might have more to do with your ability to cultivate and use willpower than you might initially think. Thankfully, as adults, we have at least some power to create that environment by choosing our friends and the situations in which we put ourselves.

Awareness of the invisible forces that may affect willpower may, at the very least, help us be more compassionate about the failures of willpower in others—and in ourselves.

(c) Meg Selig

Check out my book on willpower: Changepower! 37 Secrets to Habit Change Success (Routledge, 2009). For more on willpower, motivation, and health, follow me on Facebook or Twitter.


(Note: For other invisible forces affecting the willpower of children, take a look at this recent article by Nicholas Kristof.)

Welsh, J. New Marshmallow Study Challenges Conventional Thinking about Willpower:

For a short video on the new study and interesting comments by the authors, click here: The Marshmallow Study Revisited:

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