Psychopathy is marked by impulsivity, an absence of guilt over hurting others, and often superficial charm.

Heroes and psychopaths may have something in common, according to new research that links psychopathic personality traits to selfless behavior.

The finding may seem incongruous, given that lack of empathy for others is a key trait of psychopathy, which is also marked by impulsivity, superficial charm and lack of remorse. But some personality traits of psychopaths may be, in some situations, positive, said study researcher Scott Lilienfeld, a psychologist at Emory University in Atlanta.

"Personality traits can be good or bad depending on the person and depending on the situation and also how they're channeled," Lilienfeld told LiveScience. Take fearless dominance, which describes a boldness frequently seen in psychopaths, he said.

"Being very fearless has its downsides to be sure, there's no question about that," Lilienfeld said. "But being fearless may have its upsides as well, like being heroic." [What Really Scares People? Top 10 Phobias]

Two sides to the same coin?

Anecdotally, many psychopaths sometimes show altruistic sides, and sometimes, heroic people act badly in other areas of their lives. In 2005, for example, an Australian businessman who saved as many as 20 people from the Indian Ocean tsunami in Thailand was arrested on assault and burglary charges upon returning home. Even serial killer Ted Bundy, who murdered at least 30 people and who is generally considered to be a psychopath, once volunteered for a suicide-prevention hotline, said Sarah Francis Smith, a doctoral candidate at Emory University and co-researcher on the new study.

"Not to say that Ted Bundy is a hero," Smith said. "But he definitely engaged in some pro-social behavior."

These contradictory behaviors spurred the researchers to examine the links between psychopathic personality traits and heroism, which they defined as altruistic behavior involving some risk, whether physical or social.

In two studies of undergraduate students, involving a total of 243 volunteers, and one study of 457 adults recruited online, the researchers asked people to fill out questionnaires regarding their heroic acts, even ones as minor as breaking up a public fight or helping a stranger push a car out of a ditch. The volunteers also took a personality questionnaire to determine their level of psychopathic personality traits — none of the volunteers were actually psychopaths, but because personality is a spectrum, some people were closer than others.

The personality of a hero

The results revealed that a couple of psychopathic traits are, indeed, linked to heroic behavior. In one undergraduate sample and in the sample of adults, a psychopathic trait called fearless dominance — essentially boldness — was linked with greater heroism and altruism toward strangers. In the other undergraduate sample, people who had higher levels of impulsive antisociality (marked by aggressiveness and antisocial behavior) were also more likely to report heroism. [7 Personality Traits You Should Change]

Fearless and antisocial people might be more likely than the average person to lie, of course. To control for that possibility, Smith, Lilienfeld and their colleagues inserted a few stealth questions into the surveys. Some were designed to out self-aggrandizers: People who answered "yes" to questions about whether they'd ever taken the controls of an airplane during a crash-landing scenario or saved people from multiple volcanic eruptions were assumed to be lying and tossed out of the study.

Some of the other questions were subtler and designed to catch people who answered questions in ways that made themselves look good. The researchers statistically controlled for high scores on these questions.

Finally, the researchers did one more test: a look at heroism, psychopathy and U.S. presidents. Using psychopath ratings from biographers and experts in presidential history, the researchers compared likely psychopathic personality traits of the 42 presidents up to and including George W. Bush with their war records. Although this study was small and limited, it did show that the more psychopathic the personality, the more likely the president was to have a record of heroic behavior in war before taking office.

"At least some of the traits of psychopaths may be adaptive at least in the short run," Lilienfeld said. In the future, he and Smith hope to study law enforcement officers, since such officers are more likely to show heroic behavior than the general population.

And whereas it may seem obvious in retrospect that the bold, impulsive or fearless might be more likely to run into a burning building or pull an accident victim from wreckage, the study could help answer the question of whether heroes are born or made. Some people are likely just in the right place at the right time and rise to the occasion, no matter their personality traits, Lilienfeld said. Others might be made for the job.

"In some cases heroism may find them," Lilienfeld said. "In other cases, they may find heroism because of who they are."

The researchers reported their results online May 29 in the Journal of Research in Personality.

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