A neuroscientist who studies rage says we’re all capable of doing something terrible

Stress makes us more susceptible to rage
Stress makes us more susceptible to rage
We may earn a commission from links on this page.

James Holmes, the 24-year-old who in 2012 killed 12 people at a screening of Dark Knight Rises in Aurora, Colorado, was always a “super-nice kid,” according to a high school acquaintance. Ed Gein, also known as “The Butcher of Plainfield,” killed two women in the 1950s, adding them to a collection of corpses he’d collected from graveyards. He was described by a neighbor as “just the guy to call in to sit with the kiddies when me and the old lady want to go to the show.”

These and similar comments about other violent criminals suggesting the normality of mass murderers are now a standard, almost clichéd, feature of the reporting on atrocious crimes. And those confused neighbors and childhood friends aren’t simply naive, they’re accurate. There is no credible way of predicting whether someone is capable of committing murder: science has not revealed any tell-tale signs that a seemingly normal person is on the path to violent criminality. As neurologist Robert Burton recently wrote in Aeon, even after 30 years of attempting to study and track patterns, psychiatrists and psychologists are terrible at predicting violence. People who do terrible things seem to be just like everyone else until the day they cross into the realm of criminal violence and, all of a sudden, they’re not like us at all.

This raises the question: If we’re incapable of knowing what others are capable of, do we know what we could potentially do? Most of us, after all, have thought about committing murder. David Buss, professor of psychology at the University of Texas-Austin,  surveyed 5,000 people for his book, The Murderer Next Door: Why the Mind is Designed to Kill, and found that 91% of men and 84% of women had thought about killing someone, often with very specific hypothetical victims and methods in mind.

The terrifying reality is that we’re biologically predisposed to violence in certain situations. Douglas Fields, neuroscientist and author of the book Why We Snap, says our brains have evolved to monitor for danger and spark aggression in response to any perceived danger as a defense mechanism. “We all have the capacity for violence because in certain situations it’s necessary for our survival,” he says. “You don’t need to be taught defensive aggression, because it’s a life-saving behavior that’s unfortunately sometimes required.”

These responses have to be quick, so as to effectively deal with dangerous situations. The problem is, they can be overly sensitive. “Of course it goes wrong [sometimes], just like any burglar alarm will have a misfire,” says Fields. “Our brian never evolved to deal with the situations and threats encountered in that environment. The modern world presses on the defense mechanism circutary in ways that can lead to misfires.”

We see this all the time, when people explode with rage in traffic jams or respond to flippant insults with physical aggression. We might like to think that people freaking out in stop-and-go traffic have a problem, and that it could never happen to us. But Fields notes that stress can make anyone more sensitive to potential threats, and more jumpy.  Even seemingly good normal people—even you—could be pushed to do something terrible.

“It’s not an opinion, it’s a fact,” says Fields. “Look at the amount of crime committed in rage, not a conniving crime but a rage-induced aggressive responses. They are people who gave no reason to believe previously that they had aggressive tendencies.”

That’s not to say we’re entirely at the whim of these aggressive reflexes. Fields says that being aware of how our brain works can help us temper our responses to perceived threats. Ideally, we could all recognize that stress makes us overly sensitive, and so understand that the jolt of rage we feel when we’re late for an important meeting and someone cuts through traffic is a misfiring, rather than an appropriate response.

Middle- and high-school students should be taught about the biological triggers for aggression, argues Fields, considering that the prefrontal cortex— the part of the brain that inhibits and controls the threat detection mechanism—is not fully developed in teenagers. “You can use the biology to help a teenager understand specifically why they’re angry, and that it’s a misfire, so there’s no advantage in an aggressive response,” Fields says. “I think that’s helpful and better than telling them to control their anger. You’re asking them to do something that their brain is not equipped to do.”

Societal pressures, including cultural norms and legal guidelines, do influence our biological impulses to murder, and the rate of human violence varies considerably across time periods and cultures. But while we’re not controlled by the evolutionarily impulses in our brain, we’re not free from them either. It’s comforting to think that those everyone who commits violence is a criminal, and fundamentally different from you. Plenty of criminals used to think the same.