Trust Us: Another Take on the Marshmallow Test


"Moot!" my son exclaimed happily. "More moot!" In order to make sure that he got his message through to me he proudly showed me his empty milk glass. I reassured him that I would return to the dining room with more milk after I checked in on dinner simmering on the stove. For a thirsty two-year-old, "right back" can feel like an eternity.

My son happily gulped down the milk upon my return. On one level, this was a benign and insignificant interaction. On another level, he was learning important lessons from a couple of genius experiments. The first one, “When I use the word ‘Moot’ will my mom bring me that delicious white stuff?” The second, more powerful, test, “Is my mom reliable? Can I trust her to follow through?”

I am not saying that if I had gotten distracted in the kitchen that he never would have trusted me again. Life (especially as a parent) is far too messy and it would be neither fair nor accurate to attach that much weight to any single interaction. There is enough parental guilt going around without adding to it unnecessarily.

But this interaction, one of many thousands in his early years, will teach him lessons that he will carry forward. The cumulative knowledge he gains will form powerful templates that will influence his behavior for years to come.

Are people trustworthy and reliable? Do they follow through on what they say they will do? Is the world safe and predictable?

Broken promises, marshmallows, and delay of gratification.

Let's turn now from milk to marshmallows. We've written extensively about the marshmallow test, a classic experiment that taught us about the important role that self-discipline plays in children's success. We've always emphasized that the marshmallow experiment is not a diagnostic tool although it can be a fun way to introduce the concept of self-discipline to your kids. This is because self-discipline is not an innate or fixed trait. Temperament plays a role, but overall it is an internal skill set that our kids can practice. As parents, we are our kids' most important coaches.

But that is not the only lesson we've learned from marshmallows. A team of researchers at the University of Rochester revisited the marshmallow test a few years ago, introducing a new element to the experiment's design. Just before the test, some of the children had an interaction with a reliable adult and others with an unreliable one. One group of kids was promised fun art supplies and stickers that never appeared while the other was given the supplies as promised.

This change to the experiment design had a major impact on children's willingness to wait for the second marshmallow. Only one of the kids who had experienced an unreliable adult decided to wait it out while over half of the kids who experienced a reliable interaction earned the two-marshmallow prize.

You have to hand it to the kids - this reflects a very rational decision-making process. Why would I wait for the second marshmallow if I don't trust that it will ever arrive?

A core ingredient of self-discipline.

Marshmallows first taught us about the importance of self-discipline. Now they are teaching us about one of the core ingredients kids need to build it: trust.

It begs us to ask the question: Do good things come to all children who wait?

We can't blame kids for their inability to delay gratification if the world hasn't taught them that this practice yields positive outcomes. Whatever the brain does a lot of is what the brain gets good at. No single interaction in the real world is going to shape a child's ability to delay gratification but ongoing lessons about trust and reliability certainly will.

Trust us.

Our kids don't build self-discipline and other executive function skills in a vacuum. They do so in families, schools, neighborhoods, and communities.

As I watched my son happily gulp down his milk I became acutely aware of and grateful for the external resources that support my capacity to built trust with this tiny person--the financial resources to give him all the milk he needs, the housing that gives him a sense of home and stability, and the jobs that enable me to both afford and be present for dinnertime.

We can't and shouldn't get our kids everything they want. The marshmallow prize is not the end game. Giving our kids consistent and predictable limits and consequences are as important as reliable rewards. But we should strive to ensure that all kids get everything they need, learn that us adults mean what we say, that we do out best to follow through on our commitments, that we apologize when we don't or can't, and that good things can come to those who wait.

Here are a couple ways that we can start building trust with our kids.


Erin Walsh, Mind Positive Parenting