Delayed Gratification: Was The Marshmallow Test Wrong?

In the 1970s and 1980s, psychology researchers published a series of papers based on a multi-year social experiment and assessment that came to be known as the 'Marshmallow Test'. In a nutshell: pre-schoolers were asked whether they wanted one marshmallow (or piece of candy) now; or, if they were able to wait a certain period of time (say 10 minutes), they would get two pieces of candy. The kids' responses were tabulated and compared within and against their peers.

Ten years later the same children were evaluated again (not with candy but in terms of performance), and it was found that those children who had been able to delay gratification as pre-schoolers were now seen to be more academically and socially accomplished than their peers who had taken the candy immediately in the first test. Researchers used this data to try and understand what the underlying factors behind the kids' responses might be (family dynamics, poverty, culture), and whether the delayed gratification-equals-better-performance skill might be something that was teachable.

Fast-forward some three decades, and a new group of researchers decided to try and replicate the Marshmallow Test and publish their results. Which they did, and which threw up some surprises when compared to the original studies. While the original Marshmallow authors had correlated the child's behaviour directly with their potential for positive future outcomes, in the new study, once multiple other factors were controlled for, they found that it was the education of the mother or circumstances of the family that was a more reliable predictor of outcome irrespective of how long the child waited for his or her treat.

It's a complex and subtle difference, but it yields an important and significant difference of perspective, one which this blog in Psychology Today attempts to unpack and explain in accessible detail. As the [blog] author points out, key out-takes may simply be: we shouldn't rush to over-generalise!