His Cheating Brain

We'll never know exactly what New York Gov. Eliot Spitzer was thinking when he allegedly arranged a dalliance with a high-priced prostitute, risking the collapse of both his career and his family. Even he may not fully understand his own actions. But all too many powerful men can at least identify with him, because they've been there. Spitzer is simply the latest married politician caught with his pants down, a group so large that "pretty soon there will be enough of them to do a scientific study," says Texas psychologist Brian Gladue. Why do men with so much to lose take the chance that they may in fact lose it? Psychologists say they fit a profile: the traits that help them succeed at high-powered jobs are often the same ones that cause them to fail in their personal lives. NEWSWEEK's Mary Carmichael asked several analysts to put the typical philandering politician on the couch.

Gimme More: Many fallen politicians fit a personality type known as a "sensation seeker," defined in the early 1970s. Sensation seekers crave novel and intense experiences more than other people do, and, as part of that, they tend to have many sexual partners. "They get a bigger kick out of things," says Marvin Zuckerman, a pioneering psychologist and author of the 2006 book "Sensation Seeking and Risky Behavior." There's chemical evidence: sensation seekers have lower levels of monoamine oxidase A, which regulates the brain's levels of dopamine, the "pleasure" neurotransmitter.

Of course, loving life isn't always a bad thing: sensation seekers are often high-energy, high-functioning people. The problem is that they never seem to get enough excitement. "Their experiences have to be either very new or very intense, or both, or else they get very restless," says Zuckerman. "When things get monotonous, they have to do something else to increase their arousal." That's the flipside of finding pleasure more pleasurable: for sensation seekers, boredom is also more boring.

Risk Rules! Sensation seekers don't just lust after things--they take them, often disregarding the risks that block their way. "When you're dealing with these high-level, in-your-face, go-for-everything guys, you're dealing with people who take a lot of risks. If that results in gains for them, they get on a roll, and pretty soon their risk management starts to fade a little," says Gladue, who is based at the University of North Texas Health Science Center. "At some point, they can't manage every aspect of their lives. They have to blow off some steam, so they say to themselves, 'this is something I'm going to do for thrills or chills or fun. It's kind of dangerous, and I'm not going to worry about it.' For politicians, that's often in their private life, where they don't have people managing them all the time. And that's where things get out of hand."

For these types, the risk itself is part of the reward. "Breaking rules is a thrill for them," says Frank Farley, a psychologist at Temple University. "Look at Spitzer: he's Mr. Rectitude, the terror of Wall Street, and he busts prostitution rings, and yet he allegedly goes into that very lions' den—the prostitution ring—and partakes. If that isn't risk-taking I don't know what other label to put on it."

He's Hormonal. Alpha males are high on testosterone, the hormone that underlies almost all the typical traits of the politico-sexual animal: high levels of testosterone make for a high sex drive, a love of risks, aggressiveness and competitiveness. "These people have a strong need to win at games, which is obviously important in power politics," says Zuckerman. Success sends their testosterone spiraling up, while a loss brings the levels down—a phenomenon that's been documented in the lab as well as in athletes and chess champions.