R. Douglas Fields, a very calm government scientist in his 50s, was emerging from a Barcelona metro stop with his daughter when a man tried to rob him.
The next thing Fields knew, he had the guy in a choke hold on the ground.
"Now I'm on the ground in a street fight, realizing that this signal never went to my cerebral cortex. There was no consciousness involved," Fields, a neurobiologist at the National Institute of Child Health and Human Development, said at a talk at New York University on April 20. "And then I realized that if there's something in your environment that can cause you to engage in violence, risk your life and limb, in an instant ... I wanted to understand how that worked."
He was so intrigued by this uncharacteristic display of rage that Fields decided to research what made him — and so many others found in news stories every day — snap. This inquiry turned into his latest book, "Why We Snap: Understanding the Rage Circuit in Your Brain."
In it, Fields has gathered what he calls the "nine triggers of rage." He has based most of the book on interviews and case studies of particular incidents of violence or heroism, but Fields also cites variousneurological and behavioralstudies throughout.
"If you learn to recognize these triggers," he writes, "you can understand why a person snapped in a specific situation." Here's what the triggers are — though bear in mind these are not justifications for inevitable violence, simply the things that frequently spark it.
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1. Life-or-death situation
This one makes sense biologically. If your life is in danger, you're probably going to react rashly, possibly in anger.
"Almost anyone, and most animals," Fields writes in the book, "will defend themselves in what is perceived as a life-or-death attack."
If you're about to die, fighting back may be your only option.
2. Insult
Men used to duel to the death over insults.
"Verbal insults are the human equivalent of head-butting — a means of challenge and establishing dominance," Fields writes in the book.
Animals fight; we sling mean words. Both can provoke an angry response.
3. Family
Like a mama bear protecting her cub, humans are also wired to guard our own family.
It's part of how our species has survived.
"Evolutionary success is determined by passing on an individual's genes to the next generation," Fields writes. "Protecting offspring, and even siblings and parents who closely share your genes, increases the odds that your genes will be passed on."
See the rest of the story at Business Insider