If scientists were to put together an experiment that was all but guaranteed to trigger full-on, red-cheeked embarrassment, filming teenagers singing Let It Go from Frozen and replaying their performance could do the job.
And so to researchers at the University of Amsterdam who invited dozens of young volunteers to the lab before breaking the news about what was needed. In front of a camera, and without the benefit of a shot or two, they were asked to sing the Arendelle song or another choice clip, before they and others watched the version from inside a brain scanner.
Through such premeditated mortification, and measurements from temperature sensors taped to participants’ cheeks, scientists hoped to uncover the signature of blushing in the brain, the neural activity underlying what Darwin called “the most human of all expressions.”
Psychologists speak of two broad theories when it comes to blushing. The one favored by Darwin suggests that ruddy cheeks arise when we think about how we should look to onlookers. The others suspect that something simpler is going on: a more spontaneous response to feeling exposed.
“Is it just being in the social situation where you are exposed and center of attention, and you feel the exposure and attention of others,” said Dr. Milica Nikolic, a psychologist and first author of the study. “Or is it more complex and that we start thinking about how we look and appear to other people?”
After advertising for young people to participate in research that involved a “social task” and watching videos in a brain scanner, the scientists heard from more than 60 young people between the ages of 16 and 20. All but two were men, which led to a decision to focus purely on young women.
On the first visit to the lab, each volunteer was asked to perform karaoke while being filmed. The songs were limited to Let it go, Adele’s hello, Mariah Carey’s All I Want For Christmas Is You and All the things she said by tATu – tracks that are considered difficult to do well and thus were contenders for causing maximum embarrassment. Again awkward smiles, arm scratching and some rightly nervous chirping.
A week later, the volunteers were back in the lab. This time they watched their performance, along with that of others, while lying in a brain scanner. They were told that others were watching their actions at the same time, a ploy designed to add to their embarrassment.
People, as expected, blushed more readily while watching themselves than others. But analysis of the brain scans revealed that the sudden flush of the cheeks may not be caused as Darwin thought. Blushing was accompanied by greater activity in the cerebellum, which the researchers link to emotional arousal, and signs in the visual cortex that people are paying close attention to their performance. Nothing in the scans suggested that people thought about how others might judge them, the researchers found.
“Blush can simply come from exposure,” Nikolic said. “In that very short moment you might not think about what I look like and so on. I think it’s more automatic than the theory says.”
Details are published in Proceedings of the Royal Society B.
