The (Honest) Truth About Dishonesty

What decisions did participants make while laboring under more and less cognitive strain? Did the “Yum, cake!” impulse win the day, or did they select the healthy fruit salad (the well-reasoned choice)? As Baba and Sasha suspected, the answer depended in part on whether the participants were thinking about an easy-to-remember number or a hard one. Those breezing down the hall with a mere “35” on their minds chose the fruit much more frequently than those struggling with “7581280.” With their higher-level faculties preoccupied, the seven-digit group was less able to overturn their instinctive desires, and many of them ended up succumbing to the instantly gratifying chocolate cake.

The Tired Brain

Baba and Sasha’s experiment showed that when our deliberative reasoning ability is occupied, the impulsive system gains more control over our behavior. But the interplay between our ability to reason and our desires gets even more complicated when we think about what Roy Baumeister (a professor at Florida State University) coined “ego depletion.”

To understand ego depletion, imagine that you’re trying to lose a few extra pounds. One day at work, you are eyeing a cheese danish at the morning meeting, but you’re trying to be good, so you work very hard to resist the temptation and just sip your coffee instead. Later that day, you are craving fettuccine alfredo for lunch but you force yourself to order a garden salad with grilled chicken. An hour later, you want to knock off a little early since your boss is out, but you stop yourself and say, “No, I must finish this project.” In each of these instances your hedonic instincts prompt you toward pleasurable types of gratification, while your laudable self-control (or willpower) applies opposing force in an attempt to counteract these urges.

The basic idea behind ego depletion is that resisting temptation takes considerable effort and energy. Think of your willpower as a muscle. When we see fried chicken or a chocolate milkshake, our first reaction is an instinctive “Yum, want!” Then, as we try to overcome the desire, we expend a bit of energy. Each of the decisions we make to avoid temptation takes some degree of effort (like lifting a weight once), and we exhaust our willpower by using it over and over (like lifting a weight over and over). This means that after a long day of saying “no” to various and sundry temptations, our capacity for resisting them diminishes—until at some point we surrender and end up with a belly full of cheese danish, Oreos, french fries, or whatever it is that makes us salivate. This, of course, is a worrisome thought. After all, our days are increasingly full of decisions, along with a never-ending barrage of temptations. If our repeated attempts to control ourselves deplete our ability to do so, is it any wonder that we so often fail? Ego depletion also helps explain why our evenings are particularly filled with failed attempts at self-control—after a long day of working hard to be good, we get tired of it all. And as night falls, we are particularly likely to succumb to our desires (think of late-night snacking as the culmination of a day’s worth of resisting temptation).

WHEN JUDGES GET TIRED