The Marshmallow Test: What It Tells Me About Kids With ADHD

Imagine sitting a young child in a room with a plate of marshmallows—one marshmallow on one side of the plate and two on the other side. Beside the child is a bell. The child is asked whether he would prefer one marshmallow or two. And most children say, “Two!”

The adult then says:

Here’s how we play the game. I am going to leave the room. While I’m gone, if you can wait for me to come back, then you get two marshmallows. If you don’t want to wait, you can make me come back right away by ringing the bell, but then you get one marshmallow, not two.

Do you think the child will be able to wait as long as 15 minutes?

That’s the experiment that psychologist Walter Mischel of Columbia University conducted in the late 1960s with 4-year-olds at Stanford University’s Bing Nursery School. It’s called the Marshmallow Test. Mischel was trying to figure out if kids could wait a longer time for a bigger reward.

This Mind in the Making video shows the experiment in action.

The results of the Marshmallow Test weren’t too surprising. Some kids could wait a long time, while others couldn’t.

What was surprising was what Mischel found when he followed up with the children years later. He explains:

The longer the young children were able to wait at age four, the better the SAT scores, the better the ratings of their ability to control themselves and to pursue their academic and other goals successfully, and the better they were doing as people in their early thirties.

In other words, greater self-control as a child meant greater success as an adult.

Now, if you have a child with ADHD or a child who struggles with impulsivity or self-control, you might be thinking, “My child could never wait 15 minutes for two marshmallows! Does that mean my child is destined to fail?”

The answer is an emphatic no.

The Marshmallow Test can’t predict a child’s future. Many kids who have ADHD and are impulsive when young go on to become very successful adults.

But just as importantly, when Mischel looked more closely at the kids who waited a longer time, he discovered something interesting. The kids who were able to wait weren’t just sitting there. They were using specific strategies to help them wait.

Some pretended the marshmallows were fluffy clouds. Some walked around the room. Some even talked out loud to themselves or grabbed their own hands.

This suggested there were self-control skills that helped the kids who had waited. These skills fall under what’s called executive functions, a sort of CEO for the brain. Executive functioning skills help with planning, organization and time management.

The good news is that these skills can be learned. In other words, kids who have self-control and impulsivity issues can pick up strategies to manage their behavior.

But how do you promote these skills with your child?

Some people think that when we talk about self-control, we’re talking about strict discipline or sitting still for long periods of time. That’s not really correct.

Research shows that self-control is learned best through play and physical activity. Playing games promotes self-control, especially games where children have to listen to the rules, pay attention when the rules change and not act on autopilot. Two great examples are Simon Says and Red Light/Green Light.

There are other ways to foster self-control in kids, too. One way is to encourage kids to set personal goals based on their interests. Another is to have kids come up with their own strategies for managing down time—such as times when they have to wait. But they need lots of chances to practice those strategies and improve on them.

To me, this is a very hopeful takeaway from the Marshmallow Test. And it’s one that is especially important for kids with ADHD.

Get more tips from Ellen Galinsky. Learn how to help kids develop a “growth mindset” and take on challenges.

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