Researchers from the Rochester University have recently revisited the 1972 Marshmallow study for which children were offered a marshmallow under particular conditions. They were told that they could eat straight away or wait and then get another one. Most children could hardly resist, which was explained with naturally low self-control.

The team from the University of Rochester first gave the children old crayons and a sheet of paper to draw on. The children were told that they would get new crayons if they waited. Only some of the children who waited actually got the new crayons, the others were put off. During the second stage of the experiment, the children then went through the marshmallow test and the researchers found that those who had learned that they could rely on a promise waited much longer before eating the candy.