Last couple posts (The Good Little Prince and The Good Little Prince 2) I’ve been writing about how willpower is like muscle power: it wears down with use.
Here’s a study that illustrates…
Imagine we’re college students sitting in a research room, staring at a plate of fresh-baked cookies. The leaders of this “food perception” study asked us not to eat for three hours prior. We’re hungry. Next to the cookies there’s a bowl of radishes.
They say they’ll leave us alone for five minutes. But we can’t eat the cookies. Only the radishes. After five minutes, they come back in, clear the tables, and give us a brief questionnaire.
Then they start a new study, right then and there, to test whether we college students differ from high school students in problem-solving ability. Of course, we want to perform well. We work on a puzzle for a while but can’t solve it. We try and try, then give up.
What we didn’t know is that we were part of three groups of participants in a study of self-control, not food perception.1
- The first group (our group) ate the radishes and then did the puzzle.
- The second group had no cookies or radishes and did the puzzle.
- The third group ate the cookies and did the puzzle.
Oh, and the puzzle was unsolvable. The researchers were measuring how long students would try before giving up.
So, how did we do? The study showed us radish-eaters fared the worst. On average, we quit after eight minutes, while the rest persisted between nineteen and twenty-one minutes.
Why? Could eating sweets lead to better productivity?
Not so fast, cookie-monsters. It wasn’t the sugar high. The group who ate nothing worked two minutes longer than the cookie-eaters.
So, what is going on here? Why did the cookie group work the puzzles for so much longer?
The truth is, the cookie group didn’t work more at all. In fact, they might have worked less. It turns out the radish group worked hardest in the experiment. But we can’t see how because we don’t define resisting temptation as “work.” The radish-eaters worked hard for five minutes prior, resisting the urge to eat the cookies. Which wore our their muscles of willpower for the puzzle task.
1Baumeister, R. F., Bratslavsky, E., Muraven, M., & Tice, D. M. (1998). Ego depletion: Is the active self a limited resource? Journal of Personality and Social Psychology, 74, 1252-1265.
