How to Have a Good Day: Harness the Power of Behavioral Science to Transform Your Working Life pdfdrive com

DECISION FATIGUE
Our days are full of small decisions. For example, if we hear someone say
something we don’t entirely agree with, we need to make a call: do we speak up
and disagree, or smile and nod? If we decide to disagree, what should we say
(and just how diplomatically should we say it)? Even these sorts of simple
moment-to-moment choices involve evaluating the pros and cons of different
options, computing how those options compare, and determining what we should
do next. So decision making requires a lot of mental energy from our brains.
And the more decisions we’re asked to make, the less cognitive capacity we
have available to assess alternatives and make good, nuanced choices—a
phenomenon known to scientists as 
decision fatigue
. It’s something you’ll be
familiar with if you’ve ever redecorated an apartment and found yourself worn

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down by the endless choices of paint color or faucet design; perhaps you ended
up saying, “I just don’t care.”
In the workplace, the effects of decision fatigue can be quite serious. In a
study by behavioral scientist Shai Danziger and colleagues at Tel Aviv
University, researchers looked at more than a thousand decisions made by
ostensibly objective judges sitting on an Israeli parole board.
1
Throughout the
day, the board would rule on whether to grant prisoners early parole or not, after
hearing them plead their case. Their day was organized into three blocks,
punctuated by two breaks. And the researchers found a very clear pattern in the
decisions the board made. If a prisoner’s case was heard at the beginning of one
of the blocks of time, when the judges were mentally fresh after taking a break,
the prisoner had a 65 percent chance of getting parole. But if a prisoner’s case
was heard toward the end of the session, before the judges were due to take a
break, the chance that the judges would be willing to revisit the sentence
dropped to almost zero, whatever the merits of the case. This pattern was
inescapable—a peak after each break, followed by a steady decline. Nothing
apparently mattered more to the outcome of a prisoner’s plea than the timing of
when it was presented to the board, and whether the judges had the energy to
engage with the case.
Studies have also shown that people make poorer purchasing decisions when
they’re tired, whether they’re shopping in a mall or buying a new car.
2
 They’re
also less likely to make the right ethical decisions or follow safety regulations. A
University of Pennsylvania study of hospital workers found that working long
hours without a break made staff less likely to follow basic hygiene rules that
they knew to be important.
3
What lies behind all these lapses is the fact that when our brain’s deliberate
system is overworked, it can’t do its job properly. That means we have less
insight, less self-control, less concentration, and less effective forward thinking.
Instead, when we’ve gone too long without a break, our automatic system takes
over. And that means we tend to reach for the easiest payoff—the quick solution,
the black-and-white answer, the short-term boost, the standard option, or the
status quo—rather than the choice that’s necessarily best.
These lapses are even more likely when we’re hungry, because part of our
deliberate system’s capacity gets diverted toward monitoring the increasingly
pressing need of our empty stomach and strategizing about how to deal with it
(“Are we going to stop soon? Should I excuse myself? Are there any cookies left

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within reach?”). Like the rest of the body, our brain also needs blood sugar to
function—but unlike other parts of the body, it can’t store much of it, so eating
regularly helps us stay cognitively sharp.
4
Given all that, it’s no wonder that even hardworking, committed people start
to flag when they’ve gone too long without a break. It’s simply not possible for
us to sustain our brain’s highest-quality attention and analysis indefinitely, even
if we would like to. That’s why so many meetings end in a slightly irritable fog:
people who haven’t taken enough breaks rarely have the mental energy needed
to finish strong.