A study that is often mentioned in ethical discussions about psychology, is ‘Personal Space Invasions in the Lavatory: Suggestive Evidence for Arousal’, conducted by Middlemist, Knowles and Matter in 1976. This team of researchers designed a creepy experiment to test how the speed and flow of men’s urination was affected by invasions of personal space.
The pilot study was conducted in the public lavatory of a US university. One observer was stationed near the mirrors, appearing to be grooming. In reality, he was keeping track of which urninals were chosen by the unsuspecting students, how close they were to other men present in the lavatory, how long it took them to start peeing after unzipping, and the time the time between the onset and completion of urination. The breathtaking conclusion: men do not like to stand close together while they pee.
Here comes the periscope
Interesting stuff, of course, but Middlemist and his colleagues suspected there was yet more to be discovered in the field of public urinating, so they came up with something better. They conducted an new experiment with two new elements. The first consisted of a confidant who’s sole purpose it was to make the subject feel uncomfortable. While the subject was forced to use the leftmost urinal (out of three), the confidant either picked the middle urinal or the one on the right. In the mean time, another observer hiding in the stall next to the subjects’ urinal was to measuring urine flow and duration, using a periscope. “An 11-inch (28-cm) space between the floor and the wall of the toilet stall provided a view, through the periscope, of the user’s lower torso and made possible direct visual sightings of the stream of urine,” the study describes the set up. Talking about invasion of privacy.
What has the world gained from this study? Well, we now know that with no one present in a lavatory, the unselfconscious urinator’s average onset is 4.8 seconds. When there’s someone present one urinal away, it takes him about 6.2 seconds to start urinating. And finally, when another toilet-goer decides to creep up next to him, it will take the poor guy about 8.4 seconds before he can relieve himself.
Read (open access) study
Middlemist, R., Knowles, E., & Matter, C. (1976). Personal space invasions in the lavatory: Suggestive evidence for arousal. Journal of Personality and Social Psychology, 33 (5), 541-546 DOI: 10.1037/0022-35126.96.36.1991