Does anyone remember this Absa ad?

In case you’re not aware of it, it’s based on the Stanford Marshmallow experiment from 1970 – often described as “one of the best known studies in the history of psychology”.

So this post is going to do two things:

  1. Explain how Walter Mischel’s test actually worked; and
  2. Dispute it a bit.

First, Walter Mischel’s Stanford Marshmallow Experiment

The basic concept:

  • Take a sample of 32 nursery school children aged between 3½ and 5½, equally split between boys and girls;
  • Place them, one at a time, in a room that consists mostly of a table, a chair, and a plate with a marshmallow on it (or an Oreo biscuit – allow the child its sugar rush of choice);
  • Offer the child a deal
  • As in: “So here’s the deal. This marshmallow is for you. You can either have this marshmallow now; or if you wait for me to come back, I’ll give you another one and then you can have two. It’s up to you. You either eat one now; or if you wait to eat it, you can eat two when I come back. Okay?”
  • Then leave the room.
  • Keep tabs on the children as they grow up.
  • See how they do in life. And how they do in school. And when the technology becomes available, perform the test again to see if there are differences in brain function.


The Results

  • A small number of children ate the marshmallow immediately, but most tried to wait.
  • Waiting strategies included: covering eyes, stroking the marshmallow, and attempting to take small bites from the bottom and then hide it*.
    *Which worked well until they applied the same principle to the top. 
  • A third of the children managed to wait the full 15 minutes.
  • Later on in life, the children that managed to exercise self-control scored significantly higher on their SAT scores (on average, 210 points higher).
  • When those children were eventually tested for different brain functioning in 2011 (41 years later, I guess they weren’t children any more), they did indeed have different brain functioning: the prefrontal cortex was more active in those that were able to delay gratification; while the ventral striatum (an area associated with addictions) was much more active in the instant-gratifiers.
  • Interestingly, the instant gratifiers were shown to be just as capable of restraint when they were tested on dry and boring subject matter – it was only when the reward was “emotionally hot” that the distinction in brain function began to emerge.
  • Which does stand to reason, because why would you get addicted to something that offers you no reward?
  • For more on the subsequent studies of these children through their lives, here’s a TIME magazine article: The Secrets of Self Control: The Marshmallow Test 40 Years Later

So obviously, this experiment began to be held up as the paragon of self-control. All that’s needed is a little self-restraint, and success is yours, baby.

But here’s the problem though: self-control is a highly irrational choice when there’s only one packet of marshmallows, and someone else is furiously shoving them down while you wait for 15 minutes in the hope that you might get more.

And there’s actually a study that’s been done on exactly that by the University of Rochester…

What Happens When You’re Constantly Disappointed

Celeste Kidd was the lead author on a 2012 paper called “Rational Snacking: Young Children’s Decision-Making On The Marshmallow Task Is Moderated By Beliefs About Environmental Reliability“.

The premise, based on her work in homeless shelters, is that children’s waiting times are very much dependent on what environment they come from.

To test this, the marshmallow experiment was repeated on two separate groups of children (14 in each group), under two different conditions.

Group 1: The Reliable Group

Before the marshmallows were introduced, the children in this group were primed to believe that their environment was one where they could rely on the experimenter.

Each child started with an art project, where there was a container of used crayons in the room. The experimenter told the child that she would go and get newer and better ones to colour with, left the room, and then returned with a rotating tray full of art supplies.

Then the child was given a small sticker to use on the art project. And again, the experimenter told the child that she would go and get better stickers, and returned a short while later with several large die-cut stickers.

Finally, the child was subjected to the marshmallow test.

Group 2: The Unreliable Group

The same set-ups applied, only each time the experimenter left the room, she would return and apologise that there were no more art supplies, or stickers, and would encourage the child to use the used crayons and small sticker that were already in the room.

And then, as with Group 1, the marshmallow task was set.

As you might guess, 9 of the children in the reliable group were able to hold out, while only one child held out in the unreliable group.

Also, the average waiting times:

Reliable Group: 12 minutes and 2 seconds

Unreliable Group: 3 minutes and 2 seconds

And in the original experiment, mean waiting times were around the 6 minute mark.

In the world of psychology, I’m given to understand that this was a resounding statistical win.

So perhaps it is trust in one’s environment that’s the better indicator of success: precisely because it permits self-control to take place when it’s appropriate?

And that definitely applies to us as adults. I mean, if you are constantly promised promotions, but don’t get them; or promised bonuses, but they don’t arrive; then how much more likely are you to take a sick day?

As the second experiment demonstrates, it would be better if those promises were never made at all.

It’s all expectations, apparently.

And the self-controlled just have theirs managed better?

PS: I maintain this is why I have no self control when it comes to mince pies. One devastating Christmas morning, there were no mince pies because no one had bought any, and the closest we could get was hot cross buns (!!) from a 24 hour garage. So now I buy them when I see them for fear that I may never find them again. 

Rolling Alpha posts opinions on finance, economics, and the corporate life in general. Follow me on Twitter @RollingAlpha, and on Facebook at