- author, Hafsa Khalil
- role, BBC News
Have you ever wondered why your cheeks turn red when all eyes are on you?
A new study published Wednesday found that blushing is a spontaneous emotional response, not the result of cognitive self-reflection.
To study the causes of facial blushing, researchers at the University of Amsterdam tried to induce it by having a group of women aged 16 to 20 sing karaoke in front of a camera, then showing them a playback of their performance.
Milica Nikolic, a developmental psychologist at the university’s Institute of Child Development and Education and lead author of the study, had already studied blushing as a physiological measure of young children’s emotions in social situations.
“I was curious what triggers blushing: is it thinking about what others think of you, or is it an automatic, spontaneous response to social exposure?” she asked.
This question is premised on two main theories about the causes of blushing: the first holds that it is triggered by complex cognitive processing such as self-reflection and self-awareness, while the second asserts that blushing is a rapid, spontaneous emotional response.
To answer this question, Nikolic and his team put subjects into a functional magnetic resonance imaging (fMRI) scanner and induced facial blushing while measuring brain activity.
Participants were a group of 40 female teenagers recruited from Amsterdam and the surrounding area, an age when sensitivity to social evaluation and self-perception is heightened.
Although the study did not intend to focus exclusively on women, the volunteers ended up being women.
People with a range of social anxiety disorders were recruited based on their responses to a questionnaire, and volunteers were not told they would be singing karaoke when joining the study, to avoid limiting the type of people enrolled.
Participants were first videotaped singing out loud four songs, including Disney’s “Frozen” and Mariah Carey’s “All I Want for Christmas Is You,” that were intentionally chosen to be difficult in order to maximize embarrassment (i.e., the likelihood of blushing). Participants then watched a video of themselves singing along with a video of a professional singer who they were told was another participant with a similar singing ability to themselves.
While participants watched the video, their brain activity was recorded to detect changes in blood flow in the brain, and their left cheek temperature was continuously measured to assess facial redness.
Nikolic explained that the researchers had two ideas: either blushing is caused by thinking about what other people think of you, activating areas of the brain involved in mentalizing, or it is caused by more basic processes such as emotional arousal and attention to the social situation.
To their surprise, the researchers found that brain regions involved in mentalizing did not become activated. Instead, they found that brain regions involved in emotion became activated when participants blushed in response to their own performance.
The study states that this suggests that blushing is a spontaneous emotional response resulting from social exposure and does not require cognitive processing.
Nikolic explained that blushing “may have an important function,” letting people know that something important is happening that could affect their social status.
Because the study only included women, it’s an open question as to whether men would respond in the same way, Nikolic said. Studies of adults have shown that women report being more shy and blushing more easily, Nikolic said.
