The Stanford marshmallow experiment is one of the most enduring child psychology studies of the last 50 years.
The test is a simple one. A child aged between 3 and 6 had a marshmallow (later experiments also used a pretzel) placed in front of them and told that if they wait, they could have a second marshmallow when the tester returned. The original study found that those who waited for the extra marshmallow had more success as an adult than those that scoffed the marshmallow down, suggesting that being able to delay gratification is an important life skill.
But since its inception, people have argued whether waiting for a marshmallow as a five-year-old can really tell you how successful, thin and educated you’ll be as an adult, or if there might be other, more complicated factors going on behind the scenes.
A new study published in the journal Psychological Science has suggested one of those factors – showing that cultural upbringing could change the way children respond.
“We found that the ability to delay gratification – which predicts many important life outcomes – is not just about variations in genes or brain development but also about habits supported by culture,” said one of the researchers, University of Colorado Boulder psychology researcher Yuko Munakata.
“It calls into question: How much of our scientific conclusions are shaped by the cultural lens we, as researchers, bring to our work?”
This is a larger problem than just some kids eating marshmallows. Historically, science – across clinical and psychology research – has a habit of having too little cultural diversity, and the new research shows why this can be an issue.
The researchers found that the 80 children in Japan were much better at waiting to eat food when asked than the 58 children in the United States. However, this was reversed when asked to wait to open gifts.
“This interaction may reflect cultural differences: waiting to eat is emphasised more in Japan than in the United States, whereas waiting to open gifts is emphasised more in the United States than in Japan,” the team write in their new paper.
“These findings suggest that culturally specific habits support delaying gratification, providing a new way to understand why individuals delay gratification and why this behaviour predicts life success.”
This small study doesn’t look into the longer-term results of the original marshmallow experiment, like whether the kids will be more successful as adults. Along with cultural differences, other studies have shown qualities like affluence are also a defining factor.
All of this is only if the marshmallow test actually holds at all. Recent follow up studies with larger groups of children followed into adulthood have shown that those who chose marshmallowey goodness straight away are not generally more or less financially secure, educated or healthy than their food-delaying peers.
It seems that 50 years later the test is still telling us things – just about our own biases rather than predicting the future of five-year-olds.