When I was training to become a social psychologist, I learned that many emotions and facial expressions seem to be universal across cultures. Recently, however, researchers have begun to debate this idea, suggesting that facial expressions of emotion are not necessarily the same from one culture to the next. A new study adds an interesting development to this debate by showing cross-cultural variation in the facial expressions people associate with having an orgasm. Yep, you read that right.

In this study, published in the Proceedings of the National Academy of Sciences, researchers used facial animation software to display randomly generated combinations of facial movements to participants. Forty participants each from two different cultures (white European vs. Chinese) saw 3,600 animations and, for each one, they had to rate whether the expression displayed was pain, orgasm, or something else. They also rated the intensity of the expression, from very weak to very strong.

Researchers then looked for statistical relationships between facial expressions and emotions. They came up with representations of what pain and orgasm looked like in each culture for each participant, and then had a separate group of 104 participants (again, half Western and half East Asian) engage in a perceptual discrimination task. Basically, they wanted to validate what they found in the first part of the study—in other words, did this new group of participants agree that the facial expressions the first group associated with pleasure and pain did indeed show those emotions?

In the words of the study’s authors, here’s what they found: “Cross-cultural comparisons also show differences in the facial expression models of orgasm, including wide-open eyes among Westerners and smiling in East Asians. In contrast, facial expression models of pain are similar across cultures.”

In other words, the look of pain appeared to be universal, but the look of orgasm did not. To get a better sense of how O-faces varied, check out the video below: