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.