You might have heard of the experiment in which children can have one marshmallow now, or wait a few minutes and have two. It’s been used as a test of self-control, and it’s been believed that you either have it or you don’t. But now researchers at the University of Colorado Boulder have discovered that social factors can influence children’s self-control.

Sabine Doebel is a postdoctoral researcher in the Department of Psychology and Neuroscience at CU Boulder. In her experiment, some children were told they were part of a group that waited for the second marshmallow. Others were told their group didn’t wait and just went for the one marshmallow. The outcomes were different.