The Marshmallow Test and Delayed Gratification: Secret to Success?

Geoffrey Kyi

Can a simple test given to a four-year-old predict education, career, and life outcomes? 

Short answer: Likely not. 

Long answer? With correlation, there is more than meets the eye. 

The Marshmallow Test

In the late 60s, Walter Mischel and his colleagues conducted the now-famous studies on self-control (or delay of gratification). Picture this: a child is brought into a room. They sit, quietly anticipating surely something science-y to come. A single marshmallow is placed on their table. 

A researcher offers the greatest of all bargains: (1) eat the marshmallow now or (2) fight all urges and be rewarded with a second marshmallow later.

Some children jumped immediately at the treat. Others waited patiently (more likely anxiously). More than a few succumbed to temptation. Yet still others held out the entire time and received double the bounty. 


Decades later, researchers conducted follow-up studies and found that children who waited for the second marshmallow (the “high delayers”) had a lower body-mass index, higher SAT scores, and better social skills than their “instant gratifier” counterparts. 


That’s a wrap, then: If you have more self-control early on in life, you’re more likely to do better. 


What we miss on first pass is that only 94 of the original 562 subjects reported SAT scores decades later. Also important is that the subjects were all children of Stanford University faculty or graduate students, making them a homogenous, non-representative sample of the general population. 

What besides self-control might be at play? A replication study by Watts et al (2018) resulted in similar findings but found that the correlation between delayed gratification and achievement was only half that of the original studies. This was further reduced by 2/3 when controlling for home environment, family background, and early cognitive ability.

With this new data on hand, we might better reinterpret delay of gratification as a result of other environmental and biological factors rather than willpower itself being a unique influence on success.  


Geoffrey is NTK’s Psychology teacher with a decade of experience in mentoring students at different levels of studies. He obtained his bachelor’s degree in Psychology from Brown University and excels in honing students’ critical thinking skills and writing skills to help them engage both Psychology and English tests with confidence.