A Full Bladder
Apparently, controlling your bladder makes you better at
controlling yourself, according to a study led by Mirjam Tuk, of the University
of Twente in the Netherlands. According to an article published last year in
Science Daily, “psychological scientists [know] that activation of bodily desires”
– sexual excitement, hunger, thirst – “can actually make people want other,
seemingly unrelated, rewards more.”
To learn more about this phenomenon, Tuk and her
colleagues set up a series of experiments to see if self-control over one
bodily desire would generalize to other areas. In the experiments, subjects consumed various
amounts of water, then were asked to make a series of decisions on rewards (for
example, whether to accept a small immediate reward vs. a larger, but delayed,
reward). Assessing the study’s results, the Science
Daily article wondered: “. . . perhaps stores that count on impulse buys should
keep a bathroom available to customers, since they might be more willing to go
for the television with a bigger screen when they have an empty bladder.”
Tuk’s conclusion, according to an article in Inc: “Because
feelings of inhibition all originate from the same area of the brain – self-control
in one area can affect self-control in others.”
Sleep works (and
coffee won’t help make better decisions)
Researchers at Harvard Medical School and McLean Hospital
have found that people who are sleep deprived perform less well on a
standardized test simulating real-life decisions. Study subjects were given a series of
decision-making challenges, then fed moderate doses of stimulants (coffee,
amphetamines) through the night. The stimulants improvee psychomotor vigilance
and alertness, but only sleep helped recovery the subjects’ decision-making
powers.
So when you face an important decision, and someone tells
you to sleep on it, take their advice – not just because they’ll have more time
to think it over, but because of the sleep itself. Here’s how the researchers
put it:
“These findings are consistent with prior research showing that sleep
deprivation leads to suboptimal decision-making on some types of tasks,
particularly those that rely heavily on emotion processing regions of the
brain, such as the ventromedial prefrontal cortex. Moreover, the deficits in
decision-making were not reversed by commonly used stimulant countermeasures,
despite restoration of psychomotor vigilance and alertness. These three
stimulants may restore some, but not all, aspects of cognitive functioning during
sleep deprivation.”
On a full stomach?
In independent research, a study led by Shai Danziger
from Ben Gurion University found that judges’ decisions were directly
correlated with food consumption – that is, the more sated the judge, the more
likely they were to grant parole. The
data, analyzed in an article last year in Discover Magazine, was quite striking
– it showed that, after breakfast, an average of 65% of inmates were granted
parole but that the number declined sharply through the morning, until the
first food break, when the number soared back to near 65%.
Danziger and colleagues analyzed 1,112 parole board
hearings made by eight Jewish-Israeli judges who averaged 22 years on the
bench. Their verdicts represented 40% of
all parole requests in a 10-month period and each judge heard between 14-35
cases (spending an average of 6 minutes on each decision). As one would expect, judges were less likely
to grant parole to prisoners considered as potential re-offenders, or those not
in a rehab program. But the influence of
their food consumption was totally unexpected, even by the judges themselves
(who Danziger interviewed).
Explained Danziger: “When we face repetitive
decision-making tasks, it drains our mental resources” and when we face “choice
overload” we opt for the easiest choice, which in this case is to deny
parole. Taking a food break appears to replenish
our resources. In explaining his
findings, Danziger noted that the results were consistent across all judges,
and were not due to discrimination or quotas.
Danziger’s bottom line: judges, even experienced ones, are
vulnerable to the same psychological biases as everyone else.
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*Tuk’s results, the
Science Daily article noted, appear to run counter to the concept of “ego
depletion” which asserts that we have a finite well of self-control (in other
words, the more we restrain ourselves, the harder it is to exert self-control in
other areas). The theory was developed
by Rou Baumeister, a psychologist at Florida State University who maintains
that decision-making ability can be thought of as a muscle. But when it comes to
your bladder, ego depletion might not apply, given that it’s an automatic,
unconscious process.
