Men are more likely to be online trolls and bullies—and it might be because, deep down, many of them are narcissists.

New research from Brunel University and Goldsmiths, University of London has linked narcissism to antisocial online behavior like attention-seeking and bullying. The research team found that men were more motivated than women to use Facebook in these ways, and that this could be explained by the fact that they were more narcissistic.

According to Brunel, this is the first study to confirm a link between the psychological trait and trolling.

"We were interested to study this area after we ourselves were trolled online in response to some of our previously published research," explains Goldsmiths co-author Dr. Nelli Ferenczi. "This made us wonder if men are more likely to troll then women, and why."

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Researchers sent 573 participants an online survey asking them to rate themselves on a 13-point narcissistic personality scale. They were also asked about their relationships with other people, as well as their use of Facebook, like if they used the social network to be mean to people or to brag about themselves.

While women were more likely to use Facebook for prosocial reasons like keeping in touch with people or to feel closer to others, the study found that men were more motivated to use Facebook antisocially. "Women do engage in trolling, though perhaps not as often as men," Ferenczi says.

Previous studies have shown that men consistently rate higher on narcissism measures than women. Building on this existing research, the researchers discovered that men reported greater levels of narcissism and were more likely than women to use Facebook for nefarious reasons, like bullying, trolling, or self-promotion. Women, on the other hand, were less likely to troll others and preferred to use Facebook to connect with others in a positive way.

So what might be making men act horribly online? "People with narcissistic tendencies may behave in hostile ways as a response to comments they perceive are negative," Ferenczi explains. "They may also behave in hostile ways because they are prone to aggression and manipulative behavior. Underlying a hostile action might be the intent to re-establish power and self-esteem. Finally, some research indicates that narcissism is linked with a drive for negative social influence and power which may also explain in part the attraction of hostile attention."