Can a Full Bladder Make You a Better Liar?

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Your little white lie might go over best if you say it right before you head to the bathroom. A new study finds that a full bladder makes people more natural liars. The study is published in Consciousness and Cognition

In order to examine what’s called the inhibitory-spillover effect, in which the act of performing one task helps us to accomplish another, Claremont Graduate University and California State University–Fullerton researchers had participants drink water, and then lie.

After all participants used the bathroom to ensure a level playing field, they were divided into two groups. One group was instructed to drink five cups of water, while the other group, the control, was told to drink just five sips. Both groups waited about 45 minutes, enough time for the full-bladder group to begin to feel antsy about needing to pee. Then, randomly selected participants sat down with an interviewer and lied about their opinions on certain topics, attempting to convince the interviewer of their sincerity. (They were told they would receive gift cards for fooling the interviewers.) Other participants were told to tell the truth about their opinions. The interactions were taped, and later another group of observers watched the videos to judge the participants' behavior. They assessed apparent levels of anxiety and confidence to determine whether it seemed like that person was lying or telling the truth. 

The participants who had full bladders were deemed better liars. They showed fewer behaviors that might indicate they were lying, and more that indicated they were telling the truth—and they told longer, more complex fabrications than the people who really were telling the truth. The same pattern did not apply to those who only drank a little water, and so didn't have any bladder pressure to distract them.

The results suggest that holding a full bladder boosted the liars’ ability to inhibit their instinctive truth-telling tendencies. Normally, in order to lie, you have to overcome a natural inclination to tell the truth, which requires a certain degree of conscious control over that instinct. It could be that because the participants' full bladders distracted them from the task at hand, they didn't focus as much on the act of lying, which in turn made them behave more naturally during their deception.

Though it may seem like a strange connection, previous research has also indicated that the self-control you exert to keep from wetting yourself can spill over into other domains of self-control, like waiting longer for a larger reward.   

But before you try out this method, ask yourself: Are these benefits worth a bladder infection?

[h/t: The Cut]