People Are Better Liars When They Have to Control Their Bladders

The urge to pee could mean better fibbing.

Comics Wikia/Lying Cat, Saga

It might be easier to pass off bullshit as truth if you’re full of pee, according to a small study from a group of cognitive psychologists at California State University in Fullerton. The claim: A full bladder requires physiological impulse control, which bleeds over into heightened cognitive control — a theory known as the inhibitory spillover effect.

The scientists had 22 students either lie or honestly state their opinions on gay rights, gun control, and other social issues during an interview. Were the students successfully mendacious, the researchers promised a sweet, sweet $10 gift card for duping the interviewers.

The twist, as the scientists laid out recently in Consciousness and Cognition, was that half the students were primed to be bursting at the seams. After taking the students’ actual opinions in a questionnaire, the researchers had the students use the restroom to clear out the ol’ peebag. In a devious bit of experimental design, the psychologists had the kids drink either 50 or 700 mL of water in what the students were led to believe was an unrelated water taste study. This was followed by a 45 minute waiting period, to make sure the water had wound its way to the appropriate coed organs.

Does this mean that people who are better at controlling their bladder are more convincing liars? Not quite: Mastery of bladder control wasn’t measured, only whether or not a student was full of water. If you did have to go, the interviewers rated you as more anxious — regardless of whether you were being honest or not. Observers found that those liars who needed to pee gave longer, more detailed answers, and seemed the most confident and convincing.

Before you go chug a 32-oz Slurpee prior to contesting that speeding ticket, two things: First, this was a fairly small investigative study. And when it comes to holding your urine and lying, you’ve got to toe the line, the psychologists say. “If it’s just enough to keep you on edge, you might be able to focus and be a better liar,” lead author Iris Blandón-Gitlin told New Scientist.

That a full bladder can influence life choices isn’t an entirely novel idea — five years ago, a Dutch psychologist proposed that people with fuller bladders make better decisions, at least in lab assessments.

In other pee science, the discovery that mammals all pee at the same rate, broadly speaking, just won an Ig Nobel Prize.