© ShutterstockWhat makes some people suppress their worst fears and do the right thing?
Though Fleming later engages in battle and proves his courage, he wonders why he fled in the first place. From writers to philosophers to heroes themselves, people for generations have pondered the question: what makes people act bravely? Thanks to recent research into fear regulation in the brain, neuroscientists are starting to answer such questions, revealing how people think about the interplay between individual and societal benefits. Understanding the intricacies of the fear response could someday lead researchers to new treatments for mental illnesses like PTSD, but for now, they have more questions than answers.
"You read about these stories about people confronted with a bear in the woods, and they end up fighting with it. I remember hearing in Canada this guy essentially punched a bear in the nose," says Leaf Van Boven, a professor of psychology and neuroscience at University of Colorado, Boulder. For researchers like Van Boven, studying fear and bravery could be considered two sides of a coin.
Fearful amygdala
At its most basic, bravery can be defined as action in the face of a threat. When confronted with hazards like dangerous predators or other attackers, humans and animals share the same evolutionary reactions—they might freeze in place, run away to avoid the threat, or act to neutralize it.
All of these reactions stem from the amygdala, a tiny brain structure that regulates fear response and emotional processing, says Daniela Schiller, an assistant professor of psychiatry and neuroscience at the Mount Sinai School of Medicine in New York. The amygdala is connected to many of the brain's major areas, including the prefrontal cortex, in which higher-order thinking takes place, and the ventral striatum, which is involved in the reward system and forming habit.
When a person is confronted with a threat, the prefrontal cortex and ventral striatum assess the situation to determine what benefits can be gained from any type of action. Sometimes it's best to flee; other times, it might be in an individual's best interest to confront the threat head-on. But these calculations can vary not only in each case, but also in each person, influenced by their biology, psychology, and wellbeing in the moment.
First, some people are hardwired to simply be less fearful than others, which would make them more inclined to take action. Memory also plays a large role—"It's important to compare [this situation] to your past experience, how familiar you are with the situation, and what your predictions are for different outcomes," Schiller says. If you've experienced a similar situation before, you have a frame of reference for how to act in it. Some Hurricane Katrina survivors, for example, were found to be psychologically better prepared for dealing with the next big hurricane in 2008, Gustav, while others were more prone to be traumatized.
A reaction also depends on a person's physical state. If you're feeling weak and with fewer resources, Schiller says, your brain will probably determine that it's safer to take the avoidant path instead of engaging in a fight that you are likely to lose.
But even under the best of circumstances, it's easy for the fear to take over, for cowardice to take precedence over bravery. And this can be unpredictable. "One of the things we know from a host of studies is that people underestimate how powerful fear will be for them," Van Boven says. "When people are placed in a frightening situation, they don't realize the intensity and potency of fear in that situation. They know the right thing to do, but they just can't do it."
Fear is especially difficult to induce and test in humans in a lab. Simply watching scary images likely doesn't trigger strong responses equal to those seen in a real-life fearful situation. In a 2010 study, participants who feared snakes were asked to bring a live snake close to their faces, while their brains were being monitored in an fMRI machine. When people moved the snake closer despite their fear, brain scans showed increased activity in part of the brain called subgenual anterior cingulate cortex compared with when they chose to not bring the snake closer. Their effort to have a courageous response counteracted their amygdala's signals and took control of their actions.
When it's worth to risk it all
In order to suppress a paralyzing fear and take a risk, a person needs to have a strong incentive. Take mice, for example. Mice have the same reactions as humans to fearful situations—they either freeze, avoid the threat, or confront it, says Cornelius Gross, a senior scientist at the European Molecular Biology Laboratory in Italy. Although mice are usually avoidant and wary, Gross says, they are also social creatures, so sometimes they gain more by confronting, for example, another male that might be threatening them. "It's an opportunity to learn things, to reap the benefits of social interaction and of attachment," Gross says. "This might be a way in which these higher voluntary future-looking circuits [of the brain] might reach down to block our basic instincts to allow us to take risks."
However, it's inaccurate to say that mice can be "brave," Gross says. "Bravery is a social construct that depends on a behavioral capacity that exists in all higher animals." He prefers that we call these actions risk-taking behaviors.
Here, our earlier definition of bravery starts to unravel. Just taking a risk when you're not afraid, or don't know the possible negative outcomes, doesn't fit into our cultural understanding of what bravery is. "Bravery isn't just the absence of a fear response—one has to overcome it in order to be brave," Van Boven says. And like Henry Fleming fighting for the Union, the gains that can be reaped from these actions go beyond the individual. "There's a moral element to it, a moral imperative that is more than just survival," Van Boven adds.
This ethical component of bravery that separates it from simple recklessness is even more difficult to address scientifically—from a neurological perspective, both appear the same, Schiller says.
Individuals' varying reactions to the same fearful situations could help researchers understand how some people develop extreme fear responses or become just unable to suppress normal fears. Genetics could play a role in variations in the brain's structure that lead to this, Schiller says, "But a lot of prior experience seems to have important influence. If you learn to be afraid of something, how do you actually modify that?" Most importantly, Schiller adds, how do you alter the brain's response to risk and reward—a circuit that, if improperly wired, can cause disorders like addiction, anxiety, phobias and PTSD? Figuring out the individual differences that caused the error in the first place might help researchers find better ways to correct it, either through relearning or with pharmacological agents.
Bravery, like many socially valued traits such as generosity and compassion, is deceptively simple. From a neuroscience perspective, the brain can suppress its fear response in order to achieve a greater benefit in the big picture. But how exactly this is done and why some people's brains can does it better than others remains unclear. "It's very elusive—if we want to be philosophical, [brave actions] may not be that brave," Schiller says. "There's no real science of bravery, it's the science of fear and avoidance. But I agree that sometimes it's just a branding issue. You can say you study courage instead of studying fear."
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