Magic Marker Experiment

A class I am taking highlighted an experiment from the ’70s done by Lepper et. al. where they experimented with pre-school students. They observed the students and their propensity to choose to engage in an activity, drawing with magic markers, then divided them into three groups:

  • No Treatment
  • An unexpected award after engaging in the activity
  • Telling the students they would receive an award if they engaged in the activity

After the treatment, it was observed that the first two groups played with magic markers just as often as before the treatment. The group that was enticed with the reward engaged with magic marker significantly less after the treatment.

Lepper wanted to build evidence for the overjustification effect. From the paper:

In a self-perception analysis, this outcome is simply the result of a self-directed inference process. In the low-justification conditions, the subject infers from his behavior and the lack of apparent external pressure that he must have wished to act as he did; while in the high-justification conditions, the subject infers that his behavior was determined by the external pressures in the situation.

The Wikipedia entry on this highlights a number of counterpoints and perspectives to the narrative presented in the study. The effect is true. It has been reproduced repeatedly in several contexts. The mechanisms are still unclear to me.

It reminds me that we have to be careful with each other. If we try to change someone, we just might. Just not in the way to expect.