For a long time, the commonly held belief among psychologists was that willpower is like a muscle - it gets fatigued after use, but over time it can become stronger. Also, the general consensus is that we have one common pool of willpower - so after spending a day studying instead of watching reality tv reruns, you just might find yourself unable to resist the temptation of that delicious chocolate cake. Operating under this assumption, scores of research studies showed that people get depleted after engaging in a task that requires willpower.
A quick digression: one famous task used in psychological research that examines interference and self control is called the Stroop Task. This task requires you to read a list of words out loud. In the classic version, the words are a list of colors, such as 'yellow,' 'red,' and 'blue' and you have to read them as quickly as you can. Sounds easy right? Not so fast. The words are all colored. Give it a quick try below:
First read off these:
Not too bad huh?
Now try these:
Was that more difficult? Imaging having to do this for 50+ words. Think you'd start feeling depleted? People typically do since it requires control to override the desire to say the color the word is printed in. And when people are exhausted from engaging in other depleting tasks, they take much longer to say the correct word and make more mistakes.
|Can you power through?|
These effects weren't just for performing better on a stroop task, they also found that students who believed that willpower was a limited resource at the beginning of the semester were more likely to report eating unhealthy food and procrastinating studying during finals week.
And just to drive the point home, because I think these effects are so cool. Here is an example graph of one of their findings:
The above graph shows that only people who were depleted and believed that willpower/self control is a limited resource did worse on subsequent tasks that required self control (the black bar on the far right). People who believed that willpower wasn't a limited resource showed no signs of depletion (white bar on the right).
The bottom line? Believing in an unending supply of willpower might just help you power through your next difficult task or give you the strength to resist that chocolate cake at the end of a long day! (if that's what you want of course. Sometimes a slice of chocolate cake is just what you need).
Do you believe willpower is a limited resource? If so, do you think this article might change your beliefs?
Job, V., Dweck, C., & Walton, G. (2010). Ego Depletion--Is It All in Your Head?: Implicit Theories About Willpower Affect Self-Regulation Psychological Science, 21 (11), 1686-1693 DOI: 10.1177/0956797610384745