Knowing narcissists.

Pop culture usually depicts celebrities as selfish, temperamental brats. A new study from two USC professors confirms the existence of such a "celebrity personality," together with important implications for managers in any local industry.

Specifically, the study by Drew Pinsky and S. Mark Young found that celebrities had high scores for narcissism on a standardized test. The famous even scored higher than aspiring business leaders, using MBA students as test group. According to the study, MBA students' drive for corporate leadership has linked them to narcissism in previous research.

"Narcissists generally crave attention, are overconfident of their abilities, lack empathy, and can evince erratic behavior," said Pinsky, also known as radio host Dr. Drew. "However, they are also well-liked, especially on first meeting, are extroverted and perform well in public."

Because of the TV and film industry, the Los Angeles labor pool functions as a holding tank for would-be celebrities. So it stands to reason that executives in many local companies have to deal with narcissists in above-average doses. When supervising these people in the workplace, executive coach Benjamin Dattner of Dattner Consulting m New York recommends that managers emphasize group rather than individual accomplishments, align employee rewards with organizational goals and surround the narcissist with capable co-workers who can bring rationality to decision-making.

Among celebrities, women showed stronger narcissist tendencies than men, scoring higher on the scale for exhibitionism, superiority and vanity. However, among M.B.A. students and the general population, males beat the ladies thanks to feelings of entitlement and self-sufficiency.

Narcissists tend to generate too much drama among staff, but managers shouldn't write them off completely. In his 2003 book "The Productive Narcissist," Michael Macoby argued that some of today's greatest business brains--Bill Gates, Martha Stewart, Jack Welch, Oprah Winfrey--are narcissists. Mixing their egotism with strategic skills makes them the personalities "best suited to lead during times of rapid social and economic change," according to the book.