On May 14, 1998, my life changed quite substantially: “Seinfeld” ended. At that time, I felt like I lost some of my closest friends. In fact, until I discovered that I could watch an unlimited amount of re-runs, I felt like I was missing a part of myself.Maybe you’ve felt this way about a TV show—perhaps the recent ending of “The Office” has spurred these feelings. More seriously, I am sure you’ve felt this sense of emptiness when a friend has moved or when someone has passed away or even after a breakup.

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Indeed, psychological science has known for quite some time that we define ourselves—that is, we come to know who we are as a person—through our closest relationships. When the relationships go, so goes a very part of our existence. After a divorce, for example, one of the biggest challenges people face is finding a way to revise their self-concept. I discuss this problem in a recent TEDx talk I gave here in Tucson—you might be interested in checking this out to learn about the best ways to go about “putting ourselves together” after these difficult experiences.One of the reasons these events can hurt so immensely is that in real relationships—unlike the ones with TV characters that exist only in our minds— losing a friend or lover means we lose an important source of support and understanding. Being understood and having a close other sense, know and feel our experience is the hallmark of empathy. The ability to empathize with another person is among the most critical of all our human capabilities.

New research from the University of Virginia suggests that not only is empathy hardwired in our brains, but also that our brains process information about ourselves and our friends in a very similar way. In this study, led by neuroscientist Jim Coan and his colleagues, 22 young adults, an opposite sex friend and study personnel (so-called strangers) were subjected to the threat of electric shock while the participants’ brain activity was measured using functional magnetic resonance imaging (fMRI).The experiment is a little confusing to follow, so the best way to think about it is to imagine you’re in the study. Think of yourself in a fMRI scanner. Now, you’re holding hands with either your friend or a stranger while they are under the threat of shock. These are called the “Threat to Other” conditions. Next, you are under threat of shock, while you’re either alone, holding the hand of your friend or holding the hand of the stranger. These are the “Threat to Self” conditions.

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Our brains respond quite dramatically when we are detecting a potential threat of physical pain, and these researchers have already demonstrated that neural activity under threat of shock varies quite dramatically when we are alone, with a stranger or with a lover. In this new study, the researchers discovered a very interesting phenomenon: The brain responds the same way when our friends are threatened. Results showed that the participants’ brains blurred the distinction between self and other with friends, but not with strangers. Brain mapping showed a very high correlation between the neural responses in the threat-to-self and the threat-to-friend conditions, but no such correlations between the threat-to-self and threat-to-stranger condition.

What is more, the paper goes on to show that the strength of the association between self- and friend-threat conditions depends on the degree to which participants’ rated themselves as close and interconnected to their friend. From this finding, the authors concluded that, “threat-responsive regions of the brain are capable of representing others in a manner that is very similar to the way they represent the self but tend to do so only to the extent that those others are perceived as familiar.” In other words, as far as your brain is concerned, when a close friend is in danger, it’s as if the danger were targeted at you.

When our friends are under the threat of shock, we experience that threat as real and meaningful. This is the neural basis of empathy. This is why we hurt when our friends hurt. This is also why we hurt when we lose our friends, family and lovers. Put simply, our brains and minds are organized in a manner that is deeply interconnected with the experiences of others. This may be the very essence of being human.

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Where does all of this leave us? What is the take-home message of all this work? I see two big lessons here. First, this research reminds us that the feeling of losing a part of ourselves—a part of how we represent the world—is indeed real. This does not mean that you cannot recover what is lost, but is does confirm that the loss is real. It takes time to recover, and the building of new relationships (or the rekindling of old ones) may be the way forward. When Jerry Maguire said, “You complete me,” he probably had no idea how true that was.Second, the idea of a social brain is very real. We depend on others to process complex information about the world, and our emotional states are intertwined with the emotional states of our friends, families and lovers.When you stop to think about it, this idea is pretty radical. Our brains are not designed to process information exclusively about “me” but instead wired to process information about “us” (whoever the “us” might be). For me, the upshot of this finding is that cultivating high quality relationships may be one of the most important things we can do to survive and thrive in this complex world.

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