The emphasis on willpower and the ability to control your immediate desires comes from a theory called ego depletion, developed by Dr. Roy Baumeister in the late 1990s. It says that as human beings—endowed with independence and free will—we are frequently faced with a choice between obeying our basic, low-lying urges (eating a piece of cake, sleeping in, venting our anger), or suppressing them with higher-order, more responsible choices favoring long-term benefit (eating healthy, going to work or biting our tongue). This sophisticated process of weighing opposing motivations and managing our priorities is a unique skill to humans known as “executive function,” thought to reside largely in the prefrontal cortex. The ego depletion theory tells us that whenever we have to perform this feat, it drains us a little; it uses up some internal energy. When that energy starts to run low, the power of our executive function diminishes, we become less able to override our raw desires and our decisions suffer.
For instance, one study looked at the rulings made by parole boards in Israel. Their job was to decide whether prisoners should be released on probation, which is always a tough call; it requires weighing many factors and a mistake could affect many lives. The result was that despite the best efforts of intelligent judges to make responsible decisions, as the day wore on, they became less and less likely to grant parole, eventually denying it to almost everybody. The more they made difficult decisions, the less they were willing or able to make more, so the default answer of “keep ’em behind bars” became their automatic choice.
And the activity doesn’t need to be an explicit decision. In another study, participants were asked to hold their arms in ice water for as long as they could—a task that’s simply unpleasant, and requires commitment and perseverance. Those who were forced beforehand to make a long series of arbitrary choices ended up pulling their arms out much earlier than those who weren’t drained by any prior decision-making.
For many of us, this phenomenon may sound familiar. Who doesn’t occasionally make bad decisions when they’re running out of steam? Have you ever rewarded yourself after a long day at work by skipping the gym and having an ice cream sundae? Or when a garbage truck is blocking the road back to base after a grueling shift, growled an obscenity and peeled across two parking lots rather than waiting another 30 seconds?
Decision fatigue is real, and more important, it has real implications for those of us in EMS. Although we like to think if we’re good at our job we’ll do a good job, the evidence says otherwise. And like any disease, understanding the problem is the key to managing it.
Characteristics of Decision Fatigue
To date, the literature surrounding this topic has described a number of common features. Here are a few of the most important.
- The relevant quality is self-control, that motivating fuel by which you direct your thoughts and actions. Anytime you commit to a decision or make yourself do something you’d rather not, you tax your supply of self-control, and the next time you need to do so you’ll have less of it to draw upon.
- Almost any decision-making or other task requiring self-control will drain your reserves of mental energy; however, the more weighty (high-stakes) or the more difficult (complex) the decision, the more it will cost you.
- The step in decision-making that actually drains you is not deliberating on the options, analyzing the problem or reflecting on the consequences. You only take the hit when you actually commit to one course of action; it’s when you can no longer change your mind, and all other avenues become closed, that you give up a little of your mojo.
- Although this is not yet demonstrated in any research I’ve seen, it seems true that even when you’re low on self-control, you can typically still execute extremely important tasks and decisions with reasonable fidelity; you simply “dig deep” and force yourself to rally. It’s those challenges that aren’t meaningless, but aren’t clearly major, which suffer the most.
- Your pool of self-control can be restored by adequate rest. For instance, as little as a 10-minute break between tasks restored test subjects to full performance in one experiment.
- This may sound odd, but several studies have shown that the impact of decision fatigue can be markedly reduced or eliminated by simply eating. For example, in the Israeli parole board study, when judges broke for meals, their cases immediately after the break returned to approval rates equally high as those at the beginning of the day. Other studies have shown that any intake of glucose, even an unpleasant gruel, can have a similar effect. (Sadly, although hypoglycemia seems to impair self-control, hyperglycemia doesn’t give you any superpowers.)
As for the consequences? Well, when you’re fatigued in this way, you tend to: