Remember that famous Marshmallow test conducted at California's Stanford University in the 1960s by Walter Mischel? The one that showed that those children who didn't wait to eat the marshmallow lacked impulse control? If you, like me, wondered if the subjects skewed the results, then you were on to something.
A more recent study by Richard Aslin, Celeste Kidd, and Holly Palmeri demonstrates that the ability to delay gratification is very much influenced by environment. Meaning what the children had learned to expect in their lives (reliability or unreliability) affected their ability to delay gratification.
"I hope people will be more careful to assume that a lack of restraint is a personality defect," Kidd said. "A lack of impulse control is not necessarily the reason kids make the choices they do."