Tuesday, June 5, 2012

Marshmallow Test

Marshmallow test is a very famous psychological experiment on toddlers. In this experiment, an instructor gives a marshmallow to a toddler and tells the child that he/she can either eat the marshmallow right away or can wait for the instructor to return (the instructor returns after about 15 minutes), and if upon return the instructor finds that the child has not eaten the marshmallow, the child is rewarded with another one.

This experiment does not look like a game as there is just one player i.e. the toddler. It is of course reasonable to assume that the possibility of betrayal by the instructor does not occur to the toddler; neither is that the idea behind the experiment. However, a careful consideration of human psychology and the manner in which we conceive and value time reveals an interesting feature of this experiment that can possibly legitimize it as a game.
Now fifteen minutes is a lifetime for a toddler, especially when there is a marshmallow staring at you. The child has to exercise restraint in order to be rewarded. Although the condition is presented to the child as an if-then clause, a careful examination of the decisions the child faces during the experiment reveal some interesting facets. To eat or not to eat is not the only decision the child takes. At every moment, the child is simultaneously assessing her/his ability to bear pain for the remaining of the time, and the possibility of not being able to cope up with the pressure at a later point. Moreover, the instructor never tells the child when he/she will return, adding to the uncertainty about how much time is remaining. Therefore the child is essentially playing a game with herself/himself at every moment where to eat or not to eat, and whether to trust the assessment of her/his own ability to bear the pain for the remaining time, which in this case is uncertain, form the two dimensions of the game. Notice that eating midway and eating a minute before the instructor arrives have two different payoffs. (Notwithstanding the fact that marshmallow might taste a bit sweeter after a longer wait!)

In short, uncertainty about one’s own assessments can replace the uncertainty associated with another player, making single player games possible.
You can watch this cute video with little souls battling with the temptation: 



FYI: Follow up studies after sixteen years indicated that the toddlers who chose to eat the marshmallow scored less on SAT than the ones who exercised restraint.


  1. I really like your thought process in each post of yours. This is no exception.

  2. This is third degree torture. I would eat the marshmallow and the plate too :P