Pornography exposure affects men’s attitudes towards women, but in different ways depending on the age when they are first exposed, a new study suggests.

“We found that the younger a man was when he first viewed pornography, the more likely he was to want power over women,” said lead researcher Alyssa Bischmann, a doctoral student at the University of Nebraska, Lincoln. “The older a man was when he first viewed pornography, the more likely he would want to engage in playboy behavior.”

The study of 330 male Midwestern university students aged 17 to 54 years found that the average age of first exposure to pornography was 13.37 years old, the American Psychological Association says.

The men in the study were asked about the age of their first exposure to pornography; whether this exposure was accidental, sought out, or forced; and what their answers were to 46 questions designed to measure two “masculine norms.” These two norms were playboy/sexually promiscuous behavior and seeking power over women.

Study co-author Chrissy Richardson, also from the University of Nebraska-Lincoln, said the research provides further evidence that pornography viewing has a real effect on men, especially on their views towards sex roles.

The researchers were surprised by their findings; they had expected that early exposure to pornography would be correlated with promiscuous behavior. This raises more questions to be examined, Richardson said.

About 43.5 percent of the men said their first exposure was accidental, 33.4 percent indicated it was intentional, and 17.2 percent indicated it was forced. The nature of the men’s first exposure to pornography appeared to have no significant association with the men’s attitudes.