Petraeus May Have Been Felled by His Own Brain Chemistry

“Power corrupts, but too much testosterone just makes you stupid.”

This astute comment followed a blog post by New Yorker writer Jon Lee Anderson on the still-unfolding sex-lies-and-email scandal involving former CIA director David Petraeus, his biographer Paula Broadwell, and a growing cast of supporting characters. The post set Petraeus’s fall against a backdrop of hero worship stoked by a desire to reimagine the Iraq War. OK, but let’s get back to that testosterone.

What psychologists and neuroscientists who study power are finding is that it corrupts in part because of the surging testosterone that comes along with it—and the concomitant decline in the stress hormone cortisol. A little of this swirling hormonal cocktail can do wonders, but a lot can make people, well, stupid. In studies, the magnitude of the hormonal shift in folks given a sense of power corresponds with cognitive and behavioral changes that make them bolder and more charismatic, but also more reckless and less moral.

Before digging into this research, it’s worth saying that none of us is a slave to our hormonal ebb and flow. We make our choices, and we should own the consequences. But here is yet another powerful man brought low by a lack of power over himself. And once again the question arises: what’s with these guys? What is it about traditional power that’s so corrosive to willpower?

In several recent studies, a trio of researchers—Dana Carney, Amy Cuddy, and Andy Yapp—have put power under the microscope. They started by giving some subjects a sense of power—either by randomly assigning them to be a boss with authority over fellow subjects, or merely by having them stand alone for a minute or two in expansive postures (think Superman) before they begin various lab tasks. Before and after the poses, the researchers took saliva samples to check their subjects’ hormone levels.

What did they find? A sense of power, whether induced by perceived hierarchy or simple physical posture, triggers a testosterone boost and a cortisol dip. It also leads to a corresponding increase in risk-taking and abstract thinking. Subjects told to make an impromptu speech for a “dream job” before two stone-faced observers were given much better evaluations and were more likely to be “hired” if they had earlier stood—unobserved—in an expansive “power pose.”

But yet-to-be-published research by Carney, Cuddy and Yapp shows that these same power manipulations also make subjects more likely to keep extra cash mistakenly given to them and more likely to cheat on lab tasks, and make them better liars—that is, they exhibit fewer of the stress-induced “tells” that can accompany deception.

The researchers’ hypothesis is that the sense of having power—based in reality or not—changes the brains’ risk-reward dynamic, possibly because the accompanying hormonal shifts goose the brain’s reward system while silencing the neural alarm bells that induce caution.

There’s more to this power paradox. In recent years, studies of what makes successful people tick have keyed in on willpower—called self-regulation in research circles—rather than on IQ or innate talents. It’s the people with loads of willpower who keep their focus on long-term goals, work harder, and avoid easy distractions, and thus overcome setbacks that would slow or stop the rest of us.

Angela Duckworth, a psychologist at the University of Pennsylvania, studies a type of self-regulation she calls “grit”—measured by a “Grit Scale” of 12 questions such as “I finish whatever I begin” and “Setbacks don’t discourage me.” In study after study tracking the success of high-school students, spelling-bee contestants, and military cadets, grit scores out-predict IQ and other standard diagnostic measures.

Let’s go back to the disgraced Petraeus. He was always the classic overachiever: graduated near the top of his class at West Point, completed Ranger School, earned a doctorate in International Relations from Princeton, and rose quickly through the ranks to become a four-star general in the Army before becoming CIA chief in 2011. Whatever else you think of the man, it’s fair to say that David Petraeus had grit galore.

But in the end, all the power we entrusted him with may have literally changed his brain, leading him to take more risks than he otherwise might have.

As Anderson put it in The New Yorker: “Petraeus was felled by that simplest and most time-honored of weaknesses: lust, for his own—let’s be honest here—hagiographer.”

So while grit—or willpower, or self-regulation, or whatever you want to call it—may beget success, the power that often accompanies that success can undermine this critical trait and invite ruin with remarkable swiftness. As the commenter put it best, it can make you stupid.