Is your emotional style getting you down? Research finds the neural basis of your responses to life-and how you can change them.
If you believe most pop psychology, you probably assume that most of us react to life events in just about the same way—there is a grieving process, a sequence of events when we fall in love, a standard response to being jilted.
But these one-size-fits-all assumptions are not true. In decades of research into the neurobiology of emotion, I’ve seen thousands of people who share similar backgrounds respond in dramatically different ways to the same experience. Why does one person recover quickly from divorce while another remains mired in self-recrimination or despair? Why does one sibling bounce back from a job loss while another feels worthless for years? And why can one father shrug off the botched call of a Little League umpire who called his daughter out while another leaps out of his seat and screams at the ump until his face turns purple? The answer that has emerged from my research is that these differences reflect what I call Emotional Style—a constellation of reactions and coping responses that differ in kind, intensity, and duration. Just as each person has a unique fingerprint and a unique face, each of us has a unique emotional profile.
That may seem as obvious as stating that everyone has a unique personality. But personality is not grounded in identifiable neurological mechanisms; it has not been traced to specific patterns of neural activity in the brain. This is where the theory of Emotional Style breaks new ground: through neuroimaging and other methodologies, I have traced Emotional Style—and, specifically, the six components that make it up—to patterns of activity throughout the brain.
In making those discoveries, I have found that, in contrast to the longstanding scientific orthodoxy, Emotional Style arises partly from activity in regions involved in cognition, reason, and logic—functions that textbooks tell us are as unrelated to emotions as apples are to squid. That has come as a shock to defenders of the view that cognition—which many psychologists and neuroscientists consider the most exalted human capacity—and emotion (viewed as a lesser, almost animalistic trait) run on separate, mutually independent brain circuitry: the former in the “highly evolved” frontal cortex and the latter in the limbic system, which in humans is not much different from that of other animals. In showing that cognition and emotion are not so separate after all, these discoveries have rehabilitated emotion. From a behavior that was, as recently as the 1970s, studied for the most part only in rats and other lab animals, human emotion has now assumed as important a place in neuroscience as thinking.
Locating the bases of emotion at least partly in the brain’s seat of reason has several practical implications. None is more intriguing than this: it is possible to transform your Emotional Style through systematic mental practice.
It is hard to exaggerate what a break this is from the conventional wisdom in psychology and neuroscience. From the earliest days of brain mapping—determining which regions are responsible for which functions—neuroscientists traced feelings and thoughts to structures that were barely within hailing distance of each other. The limbic system deep in the brain, including the amygdala and hippocampus, seemed to be the brain’s holy terror of a 2-year-old, the site of anger, fear, and anxiety, as well as positive emotions. The frontal cortex, just behind the forehead, was the exalted thinker, where forethought and judgment, reason and volition, attention and cognition came from. As recently as the 1980s, neuroscientists focused almost exclusively on cognition and the other functions of the frontal cortex; emotions were deemed of so little interest that neuroscience left them to psychology.
The first crack in this wall came in the 1980s. The neurobiology of emotion was still a backwater, but a few scientists were beginning to pay more attention to feelings, particularly in the context of depression. Inspired by one of them, I launched experiments using electrodes to measure brain activity in people whose emotional state we manipulated in the lab. By showing them upsetting, fearful, or uplifting videos and photos, for instance, and monitoring their response, we discovered that how well and how quickly a person is able to bounce back from adversity has nothing to do with activity in what scientists identify as the brain’s emotion centers. Instead, the ability to vanquish feelings of grief, anger, or other negative emotions reflects activity in the prefrontal cortex. In this research, we found that Resilience—one of the six elements of Emotional Style—is marked by greater left versus right activation in the prefrontal cortex: a lack of Resilience comes from higher right prefrontal activation. The amount of activation in the left prefrontal region of a Resilient person can be 30 times that in someone who is not Resilient.
Almost immediately, we faced a new question: what does the prefrontal cortex do when it comes to emotion? After all, the prefrontal cortex was, and is, known to be the site of the highest of higher-order cognitive activity, the seat of judgment, planning, and other executive functions. How could it possibly play a role in a key element of our emotional lives?
One clue came from the large bundles of neurons running between certain regions of the prefrontal cortex and the amygdala. The amygdala is involved in, among other things, negative emotion and distress, snapping to attention and activity when we feel anxious, afraid, or threatened. Perhaps the left prefrontal cortex inhibits the amygdala and, through this mechanism, helps to facilitate rapid recovery from adversity.
In a major experiment testing this idea, my colleagues and I fitted volunteers with electrodes to measure their brain activity and then showed them 51 pictures on a video monitor. One third of the pictures depicted upsetting images such as a baby with a tumor growing out of his eye; one third showed something happy, such as a radiant mother embracing her infant; one third showed a neutral scene such as a nondescript room. Sometimes during or after a picture, the volunteer would hear a short burst of noise that made him blink involuntarily. A large body of research had established that when people are in a negative emotional state, these blinks are a little stronger than when we are in a neutral emotional state, and much stronger than in a positive state.
What we found, in a nutshell, is that people with greater activation on the left side of the prefrontal cortex recovered much more quickly even from the strongest feelings of disgust, anger, and fear evoked by the images. From this, we inferred that the left prefrontal sends inhibitory signals to the amygdala, instructing it to quiet down. Activity in the left prefrontal cortex actually shortens the period of amygdala activation, allowing the brain to bounce back from an upsetting experience.
Thanks to MRI, we now also know that there is a second element at play: the more axons you have connecting one neuron to another between the prefrontal cortex and the amygdala, the more resilient you are. The less of this “white matter”—that is, the fewer the highways leading from the prefrontal cortex to the amygdala—the less resilient you are.
In other words, both prefrontal-cortex activity and the number of pathways sending calming signals to the amygdala determine just how easily a person will bounce back from adversity. Through these two mechanisms, our “thinking brain” is able to calm our “feeling” self, enabling the brain to plan and act effectively without being distracted by negative emotion—not a bad working definition of Resilience.
This is the kind of statement that makes people worry: Oh great, I must not have many connections between my prefrontal cortex and amygdala, so I’m doomed to melt into a neurotic puddle every time I experience adversity. And indeed, for decades, neuroscientists assumed that the adult brain is essentially fixed in form and function.
We now know that this picture is wrong. Instead, the brain has a property called neuroplasticity, the ability to change its structure and function in significant ways. The brains of virtuoso violinists, for example, show a measurable increase in the size and activity of areas that control the fingers, and the brains of London taxicab drivers, who learn to navigate the complicated network of streets in that city, show a significant growth in the hippocampus, an area associated with context and spatial memory. But the brain can also change in response to messages generated internally—in other words, to our thoughts and intentions. In my favorite example of how “mere” thought can change the brain in fundamental ways, scientists led by Alvaro Pascual—Leone of Harvard University had volunteers imagine practicing a simple five-finger keyboard piece over and over for a week. Result: the region of the brain’s motor cortex that controls the fingers of the right hand expanded. Thinking, and thinking alone, had increased the amount of space the motor cortex devoted to a specific function.
When it comes to your Emotional Style, we know that changes to the neural structure of brain are possible. We don’t know exactly how much plasticity the brain has, but we do know that some neurally inspired interventions—forms of mental training that target patterns of brain activity—can work. Mental activity, ranging from meditation to cognitive-behavior therapy, can help you develop a broader awareness of social signals, a deeper sensitivity to your own feelings and bodily sensations, a more consistently positive outlook, and a greater capacity for Resilience. Do you feel yourself to be too negative in outlook? Pay heightened attention to the ways in which you can be more generous and upbeat, through processes therapists call “well-being therapy.” Are you very Self-Aware, so much so that your internal chatter threatens to take over your day-to-day life? Practice observing your thoughts, feelings, and sensations nonjudgmentally moment by moment.
This practice, known as “mindfulness meditation,” is one of the most effective tools for changing our Emotional Style. In patients with depression—whom we call “Slow to Recover” on the Resilience scale—every disappointment and setback is shattering. These patients need to increase activity in the prefrontal cortex (especially on the left side), to strengthen the neuronal highways between it and the amygdala, or both. Mindfulness meditation cultivates greater Resilience and faster recovery from setbacks by weakening the chain of associations that keep us obsessing about and even wallowing in a setback. It strengthens connections between the prefrontal cortex and the amygdala, promoting an equanimity that will help keep you from spiraling down. As soon as your thoughts begin to leap from one catastrophe to the next in this chain of woe, you have the mental wherewithal to pause, observe how easily the mind does this, note that it is an interesting mental process, and resist getting drawn into the abyss.
If you instead wish to move toward the Slow-to-Recover end of the Resilience dimension—perhaps you find you are not taking in the pain of others or yourself carefully enough—then you need to weaken connections between the prefrontal cortex and the amygdala. One strategy is to focus intently on whatever negative emotion or pain you are feeling, or the pain of someone you know. This can help sustain the emotion, at least for a time, and increase activation of your circuitry that is involved in pain and distress.
The goal here is not to go from one extreme to the other: I’m not trying to change you from Slow to Speedy (or vice versa) on the Resilience scale, or from Cassandra into Pollyanna in your Outlook. Changing the patterns of activity and even connectivity that underlie the facets of Emotional Style is highly personal. It depends on what works for you.
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