A persuasive study out of Duke University (2010) suggests that not only is self-control important for the health, wealth, and public safety of the population, but that childhood self-control can predict physical health, substance dependence, personal finances, and criminal offending outcomes, following a gradient of self-control.
The psychologists followed a cohort of 1,000 children from birth to the age of 32: children who showed early signs of self-control (as opposed to those who became easily frustrated, lacked persistence in reaching goals or performing tasks, or had difficulty waiting their turn in line) were three times less likely to develop addictions or commit a crime by adulthood; they were also healthier and wealthier than their more impulsive peers. Likewise, smoking and getting pregnant during adolescence were highly correlated with low self-control in childhood.
This new research recalls and confirms the findings of the famous Stanford Marshmallow study, the 1972 project considered “one of the most successful behavior experiments ever” (Rebecca Camber, 2008).
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The purpose of the original Stanford study was to discover at what age children develop the ability to defer gratification, the ability to wait to obtain something that one wants. Children aged 4-6 were led into a room, empty of distractions, where they were offered a marshmallow (or the treat of their choice); they were told that if they waited for fifteen minutes without eating it, they would be rewarded with another of the same.
Psychologist Walter Mischel who directed the study observed how some would “cover their eyes with their hands or turn around so that they couldn’t see the tray; others start kicking the desk, or tugged on their pigtails, or stroked the marshmallow as if it were a tiny stuffed animal.’ Still others would simply eat the marshmallow as soon as the researchers left.
Of the 600 children who took part in the experiment, a minority ate the marshmallow immediately. Among those who attempted to delay, one third deferred gratification long enough to get the second marshmallow. Age was a major determinant of deferred gratification.
In the follow-up studies, Mischel discovered there existed an unexpected correlation between the results of the marshmallow test, and the success of the children many years later. Mischel’s 1988 study showed that “preschool children who delayed gratification longer in the self-imposed delay paradigm, were described more than 10 years later by their parents as adolescents who were significantly more competent.” A second follow-up study in 1990, showed that the children who were able to delay gratifications scored an average of 210 points higher on the SAT.
A 2011 study of the same participants indicates that the characteristic remains with the person for life; ; those who were able to wait the 15 minutes were significantly less likely to have problems with behavior, drug addiction or obesity by the time they were in high school, compared with kids who gobbled the snack in less than a minute.