In a 2011 study, researchers followed a group of judges deciding whether or not to offer imprisoned individuals a chance at parole. Logically, one might expect things like an imprisoned person’s crime, existing sentence, and current behavior to be the primary considerations. But while those details were duly examined, one variable had a remarkably large impact: the time of day. Imprisoned people who met with the board in the morning were far more likely to receive parole than those whose cases were reviewed in the afternoon, even if their crimes and sentences were practically identical.
This finding might seem strange, but the researchers’ explanation was simple: in the afternoon, the judges were likely exhausted. Specifically, they were experiencing decision fatigue. This kind of cognitive exhaustion occurs after a period of extended decision making and it can make people more impulsive and less confident while making choices. The dangers of decision fatigue are clear in high-stakes scenarios like this study, but it can have a serious impact on our day-to-day lives as well. So what kinds of choices lead us to this state, and what can we do to fight fatigue?
Everything our bodies do— whether physical or mental— uses energy. But while it’s unclear exactly what resources are depleted during mental strain, studies have found many individuals seem to have a daily threshold for making decisions. And once that threshold is met, most people make the conscious choice to “take it easy” and save serious thinking about any new decisions for another day. How quickly you reach this threshold depends on several variables, including the frequency, complexity, and novelty of the decisions you have to make. For example, choosing what to eat for breakfast isn't very taxing. Not only is this decision limited by what's available, it's also a choice you expect to make once a day with fairly low stakes. And even when you’re not quite sure what to eat, the time between this minor decision and the next one should give you ample room to recover whatever cognitive energy you expend.
But let’s imagine something much trickier. For example, your car suddenly breaks down and you need to replace it right away. This is an unexpected, complicated decision with serious consequences. In this case, there are countless options to choose from, and you won't find them all in one place. To make the optimal choice, you’ll need to do hours of thoughtful research to consider the various pros and cons. And since this is a decision you don’t often make, you’ll also have to identify what considerations are most important. The time pressure can add additional stress both during the decision-making process and afterward, as you expend more energy wondering if you would have made a different decision with more time.
After just a single decision of this magnitude, most people would have already reached their decision-making threshold. But in professions where individuals need to make multiple high-stakes decisions every day, decision fatigue can be much more dangerous. Judges, like those in the 2011 study, often encounter difficult decisions back-to-back, with no time to recover. Many researchers are especially concerned about decision fatigue in medicine. Doctors often work long shifts full of life-or-death decisions, and some studies have found that medical workers are much more likely to make critical mistakes when working extended shifts.
Addressing these issues requires institutional changes, but there are much more direct ways most of us can avoid fatigue in our daily lives. One simple strategy is to make fewer daily decisions, tackling your to-do list over multiple days, or even removing some rote decisions from your day altogether. It’s also typically less draining to offer advice on a hard decision than it is to make that choice yourself. So it can be helpful to imagine your decisions as someone else’s before considering how the consequences impact you specifically. Finally, it's essential to remember that not every choice is equally important, and learning how to relax about the small stuff can help you save energy for the decisions that truly matter.
