You probably know some people who fit this personality profile: witty, outgoing and fun. They like to dominate the conversation, and after a while, they can be hard to be around. They're called narcissists. Their personality trait got its name from the Greek myth about a man who fell in love with his own reflection.

Now a new study finds that many of our political and business leaders are narcissists. 

"The first instance of meeting a narcissist, they're likable, they're charming, they're fun, so people rate them initially as pretty attractive people," says psychologist Amy Brunell with the University of Ohio, who researches narcissism and the narcissistic.

Recently, Brunell did some studies on the trait. She gave several groups of volunteer subjects a personality test that rated each person's level of narcissism. Then Brunell had the groups go into a room to solve a problem together. The most narcissistic people consistently emerged as the leaders of the groups. Others in the room also judged them to be their leader.

"In the third study, the rating of leadership came from experts who were actually trained to observe interactions in this group discussion," Brunell says. "They were asked, 'Who was the leader?' and even these experts said that leadership was highest among the more narcissistic participants."

Everyone has some narcissistic traits, but Brunell says problems emerge when someone is excessively narcissistic. 

"They tend to have volatile, risky decision-making," she says. "They tend to not listen as much as others. They tend to 'know it all.'"

"What narcissists will do is they will try to use others for their own self-gain. So if you're in a situation ? let's say in a workplace ? with a narcissist, and you're doing a group project and the project goes great, then they take all the credit," she says. "If the project doesn't go so well, they blame you for it."

This becomes a problem in society and in business, where narcissists frequently end up in positions of power. Brunell says that's why it's important to have limits on power, because if there aren't, a narcissist is the type of person who might abuse it.

"If they think they're going to get caught, that will keep them in line," Brunell says. "But otherwise, they're going to, you know, they're gonna risk it."

Brunell's research appears in the journal Personality and Social Psychology