In 1961 researchers coaxed crickets into cage matches — all in the name of science. Although these chirp-filled battles were seldom fatal, they were intense: “rushing forward, sparring with the forelegs, butting with the head, and grappling, wrestling, or biting with the mandibles,” the authors describe in their study. “A male is often flipped back or thrown sideways.” But the most surprising detail of the research wasn’t that crickets are scrappy fighters. It was that, after a male cricket won a bout, it invariably went on to win again and again. Loser crickets, meanwhile, continued losing.
Scientists call this phenomenon the winner effect. Studies have shown that fish and birds, rodents and race car drivers, all follow a similar pattern. Winners keep on winning and losers keep losing, even after researchers control for talent, skill, and other factors known to influence a win. Preliminary studies suggest that winning increases testosterone levels, priming winners to take risks and compete, while losing increases levels of the stress hormone cortisol, causing losers to become risk-averse and avoid competition. And recently, a study in Science pinpointed one brain region that mediates the winner effect (the dorsal medial prefrontal cortex, or dmPFC).
“The euphoria, overconfidence and heightened appetite for risk that grip traders during a bull market may result from a phenomenon known in biology as the ‘winner effect’,” author John Coates writes in his book, The Hour Between Dog and Wolf. This effect, he adds, is apparent in the literature even “when animals were evenly matched for size (or resources) and motivation.”
While studies on humans have been slow to surface, researchers have been keeping tabs on how the winner effect impacts animal territorial battles since the 60’s. Blue footed booby chicks rise and fall through the pecking order to the tune of the winner effect. Fallow deer that win horn-butting competitions go on to successfully butt even more heads afterward. Both zebrafish and mice bite and scratch, respectively, as the winner effect predicts — unless a key brain circuit known as the habenula is silenced. The most recent study in Science found similar results after silencing a different brain circuit (dmPFC) in mice, suggesting multiple parts of the brain, plus hormones, work in concert to ensure that winners have the juice to keep on winning.
Whether this applies to humans is an open question, anecdotal evidence aside. Ian Robertson, a preeminent author on the winner effect, suspects that it does. “The winner effect is something that happens across species of humans and animals,” he said in 2012. “If you win a contest—it doesn’t matter what kind of contest, it could be a chess match—against someone who is not very good, the mere act of winning will make it more likely that you will win in a big, difficult context the next time. That’s the most remarkable finding in human neuroscience.”
Indeed, there is some evidence that humans who win are wired to keep winning, much like zebrafish and crickets. One 2014 study pitted students against each other in a rigged game of Tetris and found that losers experienced drops in testosterone and went on to lose again the following day. Winners rode atop a testosterone boost and kept on dominating Tetris. In his book, Coates claims that the winner effect has been documented in tennis, wrestling, chess, and even test-taking—we ride upward spirals of testosterone, he says, from one win to the next.
At the same time, more evidence is necessary to demonstrate that human winners aren’t simply continuing to win because they’re more skilled than the competition. But if it’s proven true that humans are subject to the “winner effect”, we can draw several interesting conclusions. It would mean that self-perception is incredibly important, and that people who consider themselves successful are more likely to live happy, hormone-filled lives. It would mean that people suffering from losing streaks may literally “need a win” to get out of their slump. It would mean that “hot-hands” and “streaks” are less of a pseudoscience than once thought. It would mean that parents of millennials, who taught us that we are all winners, were onto something.
But disturbingly, it also means that defeating opponents, even when they’re no match for us, feels good. It means that bullies may be driven by pleasurable, hormone-powered feedback loops to keep on shoving smaller kids into lockers. And it means that bullied kids may be driven into submission and long-term mental health challenges as their physiologies adjust to losing.
Robertson recognizes that the winner effect can lead to abuse of power, and advises successful people to keep that in mind. “True winners appreciate that, no matter how much of chimera it is, the ego is a dangerous dog,” he writes. “The men and women who take on the burden of power and use it well always keep the dog at a certain distance and on a tight leash of accountability to principles beyond themselves. Taming ‘I’ may be the greatest challenge for mankind’s success.”