It can be mighty difficult to distinguish between an expression of intense pleasure or a grimace of pain, conclude researchers at Albright College in Reading, Pennsylvania.
The researchers came to this conclusion after studying the facial expressions of those in pain and the ones experiencing heightened sexual pleasure.
"Although very distinct emotions, facial expressions of those who are experiencing pain appear surprisingly similar to those who are experiencing heightened sexual pleasure," says Dr. Susan Hughes, assistant of psychology at Albright, and lead author of the study, titled 'Sex Differences in the Assessment of Pain Versus Sexual Pleasure Facial Expressions'.†
The researchers studied the sex differences between distinguishing facial photos of males and females, expressing either pain or sexual pleasure, by showing 91 participants photos from the Internet.†
The subjects were asked to identify the emotion expressed in the image.†
"Overall, participants were more able to correctly identify an expression of pain. Perhaps it's because it's more important that we recognize threatening events we should avoid. Or just the fact that we have more exposure to different individuals expressing pain on a more frequent, daily basis," says Hughes.†
The researcher further revealed that women were most accurate in identifying other women expressing pain.†
"This was the only condition were female raters performed better than men. It has been shown that females demonstrate a higher level of empathy and realizing other females' pain may be a result of that," says Hughes.†
"Men, however, were much better at identifying female sexual pleasure than were other women. Since there are not as many obvious cues of sexual pleasure and orgasm for women as there are for men, men made need to rely more on facial expression to determine if she's having a good time - and so that he may be invited back again," she adds.
She claims that her study is among the first to empirically examine the similarities between the appearance of facial expressions of sexual pleasure and extreme pain by looking at sex differences in the participants' perception and the sex of the image.†
"It appears that we're better at identifying pain than pleasure, especially when it's a woman in pain," says Hughes.
The study has been published in the Journal of Social, Evolutionary and Cultural Psychology.†