A new replication study of the famous “marshmallow test” designed to predict young children’s future life success based on their ability to delay gratification (or just the eating of marshmallows, as the case may be) had found its predictive power to be significantly lower than previously thought.
The study, conducted by Dr Tyler W. Watts from New York University and his colleagues found that while the original test, devised by psychologist Walter Mischel, does correlate with superior adolescent math and reading skill, the association was small and quickly disappeared after controlling for children’s early environment and familial relationships.
Furthermore, there was no indication that a higher or lower score on the test was in any way linked to later behaviour or the development of personality, which suggests that merely instructing children to forego enticing treats in favour of more gratifying things in the future may be ineffective.
According to Watts, educators would likely achieve better results by focusing on more important aspects of personality. “If intervention developers hope to generate the kinds of improvements associated with the original marshmallow study, it is likely to be more fruitful to target the broader cognitive and behavioural abilities related to gratification delay”.
One significant advantage of the new study over the original one is its larger sample size and greater representativeness – while Mischel’s study drew only on children from the Stanford University community, Watts enrolled a total of 918 children from the diverse National Institute of Child Health and Human Development Study of Early Child Care and Youth Development.
Even though the original study doesn’t exactly hold up to replication, Watts emphasised that it doesn’t mean we should ditch attempts to teach children self-control altogether. “Of course, these new findings should not be interpreted to suggest that gratification delay is completely unimportant, but rather that focusing only on teaching young children to delay gratification is unlikely to make much of a difference.”