Basic biology tells us that bravery emerges from a primal struggle between the brain’s decision-making hub, the prefrontal cortex, and the focal point of fear, the amygdala. When we find ourselves in an unexpected and dangerous situation, the amygdala sends a signal to the prefrontal cortex that interferes with our ability to reason clearly. In extreme cases, that “can be paralyzing,” says Daniela Schiller, a neuroscientist at the Mount Sinai School of Medicine in New York.
But the brave don’t succumb to fear. In some cases, they’re strengthened by the muscle memory that comes from intense training. Flight attendants, for example, practice until they’re able to empty a jumbo jet filled with passengers in 90 seconds.
So on July 6, when Asiana Airlines Flight 214 crashed short of the runway at San Francisco International Airport, Lee Yoon-Hye, 40, of Seoul, South Korea, knew what to do. After the plane struck the ground, its tail hit a seawall, ejecting three flight attendants. Lee and her remaining colleagues helped hundreds of passengers get out of the wreck and onto the runway. Nearly everyone survived, in part thanks to the crew’s unflappable demeanor.
When an emergency slide deployed in the plane, trapping panicked people, Lee handed a knife to a copilot, who punctured the slide and freed them. When Lee saw flames erupt, she tossed a fire extinguisher to a colleague, who tried to put the fire out. “We followed our training,” she told reporters. “I wasn’t really thinking … my body just started carrying out the steps needed.” After the ordeal, doctors discovered Lee had performed her job with a broken tailbone.
Lee’s ability to carry out her duties in the face of imminent danger lies in the area of the brain known as the basal ganglia. When you practice an act again and again, the responsibility for performing the action switches from the brain’s outer cortex, where it is experienced consciously, to the basal ganglia, which executes the action automatically and isn’t affected by fear.
Armies of every nation have understood this principle for thousands of years. Boot camps the world over deeply embed the fundamentals of combat into a recruit’s brain through relentless repetition. That way, when intense fear shuts down a soldier’s rational brain, he or she will still be able to function on autopilot.
Next: Why heroes risk their own lives to help others »