In the early 1970s, psychologist Walter Mischel conducted what is now known as the marshmallow test; he found that children who, left alone in a room with a plate containing a marshmallow, were able to resist eating the candy in order to be rewarded with two in the future, later showed numerous positive life outcomes. Notably, these children and fewer behavioral problems and better grades than did those who were unable to delay gratification in the test.