Take-home Messages

• The marshmallow test is an experimental design that measures a child’s ability to delay gratification. The child is given the option of waiting a bit to get their favorite treat, or if not waiting for it, receiving a less-desired treat. The minutes or seconds a child waits measure their ability to delay gratification.
• The original marshmallow test showed that preschoolers’ delay times were significantly affected by the experimental conditions, like the physical presence/absence of expected treats.
• The original test sample was not representative of preschooler population, thereby limiting the study’s predictive ability. (Preschool participants were all recruited from Stanford University’s Bing Nursery School, which was then largely patronized by children of Stanford faculty and alumni.)
• A 2018 study on a large, representative sample of preschoolers sought to replicate the statistically significant correlations between early-age delay times and later-age life outcomes, like SAT scores, which had been previously found using data from the original marshmallow test. The replication study found only weak statistically significant correlations, which disappeared after controlling for socio-economic factors.
• However, the 2018 study did find statistically significant differences between early-age delay times and later-age life outcomes between children from high-SES families and children from low-SES families, implying that socio-economic factors play a more significant role than early-age self-control in important life outcomes.

In a 1970 paper, Walter Mischel, a professor of psychology at Stanford University, and his graduate student, Ebbe Ebbesen, had found that preschoolers waiting 15 minutes to receive their preferred treat (a pretzel or a marshmallow) waited much less time when either treat was within sight than when neither treat was in view.

The Stanford Marshmallow Experiments

Mischel, Ebbesen and Zeiss (1972) designed three experiments to investigate, respectively, the effect of overt activities, cognitive activities, and the lack of either, in the preschoolers’ gratification delay times.

Experiment 1

Fifty-six children from the Bing Nursery School at Stanford University were recruited. To build rapport with the preschoolers, two experimenters spent a few days playing with them at the nursery.

Design

Children were randomly assigned to one of five groups (A – E).

The children were individually escorted to a room where the test would take place. Each child was taught to ring a bell to signal for the experimenter to return to the room if they ever stepped out.

Treat vs. No Treats Condition

Children in groups A, B, and C were shown two treats (a marshmallow and a pretzel) and asked to choose their favorite.

They were then told that the experimenter would soon have to leave for a while but that they’d get their preferred treat if they waited for the experimenter to come back without signaling for them to do so.

They were also explicitly allowed to signal for the experimenter to come back at any point in time but told that if they did, they’d only get the treat they hadn’t chosen as their favorite. Both treats were left in plain view in the room.

Children in groups D and E were given no such choice or instructions.

Children in groups A, B, or C who waited the full 15 minutes were allowed to eat their favored treat. Those in groups A, B, or C who didn’t wait 15 minutes were allowed to have only their non-favored treat.

Children in groups D and E weren’t given treats. All children got to play with toys with the experiments after waiting the full 15 minutes or after signaling.

Distraction vs. No Entertainment Condition

Children in groups A and D were given a slinky and were told they had permission to play with it.

Children in groups B and E were asked to “think of anything that’s fun to think of” and were told that some fun things to think of included singing songs and playing with toys.

Controls

Each child’s comprehension of the instructions was tested. Six children didn’t seem to comprehend and were excluded from the test. The remaining 50 children were included.

All 50 were told that whether or not they rang the bell, the experimenter would return, and when he did, they would play with toys.

Waiting time was scored from the moment the experimenter shut the door. The experimenter returned either as soon as the child signaled or after 15 minutes if the child did not signal.

Results

The results suggested that children were much more willing to wait longer when they were offered a reward for waiting (groups A, B, C) than when they weren’t (groups D, E)

The results also showed that children waited much longer when they were given tasks that distracted or entertained them during their waiting period (playing with a slinky for group A, thinking of fun things for group B) than when they weren’t distracted (group C).

Experiment 2

This test differed from the first only in the following ways:

1. Thirty-eight children were recruited, with six lost due to incomplete comprehension of instructions.
2. Thirty-two children were randomly assigned to three groups (A, B, C).
3. All children were given a choice of treats, and told they could wait without signalling to have their favourite treat, or simply signal to have the other treat but forfeit their favoured one.
4. In all cases, both treats were left in plain view.
5. Children in group A were asked to think of fun things, as before.
6. Those in group B were asked to think of sad things, and likewise given examples of such things.
7. Those in group C were asked to think of the treats.

Results

The results suggested that children who were given distracting tasks that were also fun (thinking of fun things for group A) waited much longer for their treats than children who were given tasks that either didn’t distract them from the treats (group C, asked to think of the treats) or didn’t entertain them (group B, asked to think of sad things).

Experiment 3

This test differed from the first only in the following ways :

1. Sixteen children were recruited, and none excluded.
2. Children were randomly assigned to three groups (A, B, C),
3. All children were given a choice of treats, and told they could wait without signalling to have their favourite treat, or simply signal to have the other treat but forfeit their favoured one.
4. In all cases, both treats were obscured from the children with a tin cake cover (which children were told would keep the treats fresh).
5. Children in group A were asked to think about the treats.
6. Those in group B were asked to think of fun things, as before.
7. Those in group C were given no task at all.

Results

The results suggested that when treats were obscured (by a cake tin, in this case), children who were given no distracting or fun task (group C) waited just as long for their treats as those who were given a distracting and fun task (group B, asked to think of fun things).

On the other hand, when the children were given a task that didn’t distract them from the treats (group A, asked to think of the treats), having the treats obscured did not increase their delay time as opposed to having them unobscured (as in the second test).

Final Conclusions

The studies convinced Mischel, Ebbesen, and Zeiss that children’s successful delay of gratification significantly depended on their cognitive avoidance or suppression of the expected treats during the waiting period, e.g., by not having the treats within sight or by thinking of fun things.

Walter Mitchell, professor of psychology at Stanford University, conducted this experiment on 50 children; out of these 50 children, only 7 children stopped themselves from eating marshmallows. Mitchell noted down the names of those 50 kids, and after many years he started to investigate what the position of all these 50 kids was, finally, he saw that all 7 kids were at the top post in their field (like Susan Wojcicki, the CEO of YouTube from 2014 to 2023) and the rest 43 were struggling in their lives. 

Author: Master Vikrant RohinMaster Vikrant Rohin is an international author, and more than four countries’ schools are using his books in the core curriculum of education. He is the author of twenty different subject books. History, Economics, Chemistry, Physics, English, Biology, Geography etc. Most of his students hold high-ranking positions in the public and private sectors. He has cracked the world’s toughest exam, the "Civil Services Examination (UPSC)," eight times. Always a topper in academics, he was also a top-class sportsman, a state boxer, and a basketball player.