Sexual objectification has been well-studied, but most of the research is about looking at the effects of this objectification.
"What's unclear is we don't actually know whether people at a basic level recognise sexualised females or sexualised males as objects," says study co-author Philippe Bernard of the Universite Libre de Bruxelles in Belgium.
Psychological research has worked out that our brains see people and objects in different ways. For example, while we are good at recognising a whole face, just part of a face is a bit baffling. On the other hand, recognising part of a chair is just as easy as recognising a whole chair, the journal Psychological Science reports.
One way that psychologists have found to test whether something is seen as an object is by turning it upside down. Pictures of people present a recognition problem when they are turned upside down, but pictures of objects do not have that problem, according to Bruxelles statement.
So Bernard and his colleagues used a test where they presented pictures of men and women in sexualized poses, wearing underwear. Each participant watched the pictures appear one by one on a computer screen.
Some of the pictures were right side up and some were upside down. After each picture, there was a second of black screen, then the participant was shown two images. They were supposed to choose the one that matched the one they had just seen.
People recognised right-side-up men better than upside-down men, suggesting that they were seeing the sexualised men as people. But the women in underwear were not any harder to recognise when they were upside down, which is consistent with the idea that people see sexy women as objects. There was no difference between male and female participants.
We see sexualised women every day on billboards, buildings, and the sides of buses and this study suggests that we think of these images as if they were objects, not people.
"What is motivating this study is to understand to what extent people are perceiving these as human or not," Bernard says. The next step, he says, is to study how seeing all these images influences how people treat real women.