Although only six U.S. states and the District of Colombia ban handheld cell phone use while driving, a study in the December print edition of Applied Cognitive Psychology provides evidence that talking on a cell phone can be highly distracting — enough to prevent you from noticing unicycling clowns.

Western Washington University psychology professor Ira Hyman and his students conducted two studies to evaluate the distracting effects of cell phone use in Red Square, a central location on WWU’s campus. They watched four groups of people: individuals walking alone while talking on a cell phone, individuals walking and listening to a portable music player, people walking in pairs, and people walking alone and not using electronics of any kind.

The researchers observed 317 people in the first study and found that cell phone users were the most distracted walkers. Hyman described them as “slow and zigzagging.” He and his students noticed that people using their cell phones were less likely to acknowledge others. They wondered if this was because the cell phone users were less aware of their surroundings.

To test the idea, they enlisted a unicycling clown.

Student Dustin Randall (who happened to own both a unicycle and a clown costume) rode around Red Square dressed in bright purple and yellow clothes, with a red nose and big red shoes. The researchers interviewed 151 people who walked through the square, asking first if they had seen anything unusual. Those answering yes were asked for details, while those answering no were asked point-blank if they’d seen a unicycling clown.

Seventy-five percent of the people who were walking and talking on their cell phones did not see him — until he was pointed out to them.

“The interesting thing is that they turned back around and they were surprised they missed the unicycling clown,” Hyman commented. He added that the implications are serious, and that the study demonstrates that people shouldn’t be talking on their cell phones while driving.

Seventy-one percent of the people walking in pairs said they saw the clown, 51 percent of people walking by themselves saw him, and 60 percent of those walking alone while listening to a music player saw him.

But, drum roll please, only 25 percent of cell phone users reported seeing a unicycling clown.

It kind of makes you wonder what else you miss while you’re talking on your cell phone.

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