Natural Rationality | decision-making in the economy of nature


On self-control -- an update

I discussed a recent experiment on self-control and its possible neural basis (dorsal fronto-median cortex (dFMC)) last week; The story is also covered in the new edition of Science NOW; interestingly, the same issue also presents another study about self-control, but this time in chimps: they use self-distraction in order to resist temptation. A clear case, I think, of genuine metacognition in our closest cousins.

Psychologists Theodore Evans and Michael Beran put each of four chimps in front of a container connected to a candy dispenser. The chimps could reach over and pick up the container to eat the accumulated candies at any time, but doing so stopped the dispenser from delivering any more. That allowed the chimps to delay the reward as long as they wanted--so that they could get more of it.

In another experiment, the chimps were presented with the same scenario but also given some toys. Just like fidgety children, the chimps were able to hold out longer in this situation by distracting themselves with toys, the team reports online today in Biology Letters. To test whether playing with the toys was indeed a distraction technique, the researchers set up yet another condition in which the chimps could see the candy container filling up but couldn't reach it. Most of the chimps spent significantly more time playing with the toys when they could access the container than when they could not, indicating that their play was a deliberate strategy to control the impulse to eat the candies.

Read the paper in Biology Letters:

  • Evans, T. A., & Beran, M. J. (in press). Chimpanzees use self-distraction to cope with impulsivity. Biology Letters.