Dr. Kentaro Fujita

So again, how long did they wait before they indulged in the one marshmallow?

And then they saw to what extent it was correlated with important life outcomes like academic achievement, career success, income, even things like incarceration, social relationships.

And what they found was shocking.

The longer children could wait before eating the single marshmallow, the more likely—

They were to do well in school, more likely to make more money, have more friends, have better physical and mental health, and also have lower incarceration and problematic social behavior reports.

And so this got people really excited about self-control because it was like it suggested it was a key skill for important life outcomes.

And this is what generated a lot of that excitement.

Did any of the kids actually get two marshmallows as a reward?

It depends on the data set.

So, research has now shown that the marshmallow test waiting times depend on a lot of things.

So, in the original experiments, there was something like 15 minutes.

Other experimenters have shortened that time to 10 minutes, and that's a little easier for children to do.

Another really important thing about the marshmallow test is that the child has to trust the experimenter.

If you don't trust the experimenter, why should you bother waiting?

It's perfectly rational just to go ahead and grab the one.

If you don't trust the experimenter, it's actually going to bring you two.

So there have been experiments in which the experimenter looks reliable or unreliable in front of the child, so they forget something or they remember to do something.

And when experimenters are unreliable, children do not wait.

They just go and grab the marshmallow.

And it's been argued that that's actually a sensible rational behavior.