"What's unclear is, we don't actually know whether people at a basic level recognize sexualized females or sexualized males as objects," Philippe Bernard of Universite libre de Bruxelles in Belgium said in a statement.
Study co-authors Bernard, Sarah Gervais, Jill Allen, Sophie Campomizzi and Olivier Klein said one way psychologists 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're turned upside down, but pictures of objects don't present that problem, Bernard said.
Bernard and colleagues used a test in which 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 with some of the pictures right side up and some upside down.
After each picture, there was 1 second of black screen, and participants were then shown two images, with instructions to choose the one that matched the one they had just seen.
The study published in the journal Psychological Science found people recognized right-side-up men better than upside-down men, suggesting that they were seeing the sexualized men as people.
However, the women in underwear weren't any harder to recognize when they were upside down -- consistent with the idea that people see sexy women as objects, the study said.