Why do we use words connoting physical pain to describe experiences of social rejection? Is feeling socially estranged truly comparable to feeling physical pain, or are these words to be regarded simply as figures of speech? Through a series of studies, my colleagues and I have shown that socially painful experiences, such as exclusion or rejection, are processed by some of the same neural regions that process physical pain.
Here I review the evidence that led us to the notion that physical and social pain processes overlap and the studies that directly test this overlap. I will explore some of the potentially surprising consequences of such an overlap as well as what this shared neural circuitry means for our experience and understanding of social pain.
As a mammalian species, humans are born relatively immature, unable to feed or fend for themselves. Because of this, infants, in order to survive, must stay close to a caregiver to get the necessary nourishment and protection. Later on, connection to a social group becomes critical to survival; its members benefit from shared responsibility for gathering food, thwarting predators, and caring for offspring.
Given that being socially disconnected is so detrimental to survival, it has been suggested that in the course of our evolutionary history the social attachment system—which ensures social closeness—piggybacked onto the physical-pain system, borrowing the pain signal to cue instances of social separation. Research with animal and human subjects alike has indicated that physical and social pain processes overlap. Specifically, two brain regions—the dorsal anterior cingulate cortex dACC and to a lesser extent the anterior insula— seem to contribute both to the distress of physical pain and to behaviors indicative of separation distress in nonhuman mammals.
The experience of pain can be divided into two components: the sensory component, which, in part, provides information about where the painful stimulus is felt, and the affective component, which registers the perceived unpleasantness of the stimulus— that is, how bothersome it is. Interestingly, some of these same pain-related neural regions also contribute to specific behaviors associated with being separated from a caregiver—namely, distress vocalizations.
Infants of many mammalian species emit distress vocalizations for example, crying, in human infants when separated from their caregivers. These serve the adaptive purpose of cueing the caregiver to retrieve the infant, thus preventing prolonged separation between the two.
The ACC both dorsal and ventral subdivisions plays a critical role in producing these distress vocalizations. Lesions to the ACC in squirrel monkeys eliminate distress vocalizations, whereas electrical stimulation of the ACC in rhesus monkeys leads to the spontaneous production of distress vocalizations.
Based on these findings highlighting neural regions involved in both physical pain in humans and separation distress behaviors in nonhuman mammals, we decided to investigate whether these regions would play a role in socially painful experiences in humans.
In one such study, each participant was told that he or she would be connected over the Internet to two other individuals and that together they would be playing a computer game of catch while in the fMRI scanner.
Through goggles, the participant saw cartoon representations of the two other players along with their names , as well as his or her own hand, and with the press of a button the participant could decide which player to throw the ball to. In the first round of the game, participants were included for the entire time, but in the second round they were socially excluded, when the two other virtual players stopped throwing the ball to them partway through the round. In response to this exclusion, the subjects showed significant activation in the dACC and anterior insula, two regions associated with the distress of physical pain.
Subsequent studies have supported these initial findings. Besides showing a relationship between in-the-moment reports of social distress and pain-related neural activity in response to social exclusion, 10 subjects who report feeling more rejected in their everyday social interactions show greater pain-related neural activity in response to an episode of social exclusion.
For example, viewing rejection-themed paintings, such as those by Edward Hopper, has been shown to activate the dACC and the anterior insula. Finally, rejection and exclusion are not the only elicitors of pain-related neural activity.
Other socially painful experiences, such as bereavement, appear to activate these neural regions as well. In response to viewing pictures of a recently deceased mother or sister compared with a picture of a female stranger , female subjects showed increased activity in the dACC and anterior insula.
To the extent that physical and social pain processes overlap, one might expect some interesting consequences—for example, that individuals who are more sensitive to physical pain would also be more sensitive to social pain, and vice versa. Since this hypothesis is not an intuitive one, few studies have directly investigated it. The best evidence for it comes from findings from patient populations, showing, for example, that adults with chronic pain are more likely than healthy control subjects to worry about rejection by a partner and that depressed patients with rejection sensitivity show greater pain sensitivity than do controls.
To examine this possibility more directly, we investigated whether sensitivity to physical pain in healthy subjects was related to sensitivity to social rejection.
In one study, we demonstrated that participants who showed greater sensitivity to heat-pain stimuli at baseline also reported feeling more rejected by a subsequent experience of social exclusion. A second consequence of a physical-social pain overlap is that factors that increase or decrease one kind of pain should affect the other kind of pain in a similar manner.
Thus, factors typically thought to reduce social pain such as feeling socially supported should also reduce physical pain, and factors typically thought to reduce physical pain such as pain medication should also reduce social pain. Since the original CyberBall experiment, a number of studies have replicated and extended its results. At one point, Eisenberger and her team posed a seemingly daft question: if physical and emotional pain are related, could a painkiller relieve heartache?
In the study that followed, some participants took two daily doses of Tylenol a common painkiller for three weeks while others took a placebo, and each group recorded their day-to-day emotions in a diary. By the end of the experiment, the Tylenol group reported less distress and showed less brain activity in the pain regions after being rejected than the placebo group. Still, the Tylenol study reveals something remarkable about rejection: that it can spill beyond our emotional lives and into our physical selves.
In fact, in recent years social rejection has emerged as key to a number of discoveries across psychology, neuroscience, economics, evolutionary biology, epidemiology and genetics, forcing scientists to rethink what makes us sick or healthy, why some people live long while others die early, and how social inequalities affect our brains and bodies. According to Eisenberger, the significance of social pain goes back to evolution. Throughout history, we depended on other people for survival: they nurtured us, helped to gather food and provide protection against predators and enemy tribes.
Social relationships literally kept us alive. Perhaps, then, just like physical pain, the pain of rejection evolved as a signal of threat to our lives. And simply watching videos of disapproving faces produced the same effect. But what about major blows to our need to belong? It turns out that something else happens too, when we get rejected — by spouses, bosses, peers, at work, at school, at home — and it can help us understand not only our struggle for acceptance but the often longing desperation that comes with it.
R oy Baumeister is a social scientist who has spent 30 years studying self-esteem, decision making, sexuality, free will and belonging. In a series of experiments conducted with colleagues since the late s, Baumeister found that following social rejection people become significantly more aggressive, prone to cheating and risk-taking, and unwilling to help others.
But despite their swift change in behaviour, the socially rejected subjects showed no evidence of actually feeling hurt.
This puzzled the researchers: it went against their predictions that rejection would trigger negative emotions, which, in turn, would trigger aberrant behaviour. In one study , he and his team divided undergraduates into groups of four to six, gave them some time to mingle, then separated them and asked each one to pick two other students as partners on the next task. Some participants were told that everyone had picked them, while others were told that no one had. In the end, when all the students rated their feelings, the rejected group showed no change in emotions: instead of feeling upset, they seemed to have become emotionally numb.
The same thing happened over and over, no matter how the researchers simulated rejection or measured emotion. They thought that perhaps the hurt feelings were there but the students felt too embarrassed to admit them. So in another experiment the participants had to rate how they felt about a fellow student who was in significant pain after a leg injury or a romantic breakup.
Once again, though, the socially rejected showed much less empathy, which led to the conclusion that their emotions had indeed shut down. Baumeister calls this phenomenon ego-shock — an allusion to the physical numbness that can follow injury. When you get rejected, Baumeister says, your psyche might similarly freeze up to protect you against the onslaught of emotional pain.
What is identity but the slow, lifelong accretion of gazes: us looking at ourselves being looked at by others? In one study , Baumeister asked participants to write about a major blow to their self-worth and describe their immediate reaction. Peer rejection was, by far, most frequently recounted, followed by academic and romantic rejection.
Moreover, compared with minor incidents, the aftermath of major threats provoked significantly different responses in the subjects. They were more likely to become disoriented and paralysed, as well as lose their ability to think straight and make decisions. They felt removed from their bodies, as if looking at things from a distance. The world appeared to them unfamiliar and strange. Eventually, people collect themselves, and remember who and where they are.
However fleeting, such moments of shock, of utter unguardedness, reveal something about rejection and belonging that normally remains hidden. We are more than social animals. They place us and ground us into the world. When they see us, they identify us. After all, what is identity but the slow, lifelong accretion of gazes: us looking at ourselves being looked at by others?
What we see is, largely, what they see, or what we think they see. And when they turn away, when we become unseen, in a way we cease to be. Nor does it have to be particularly overt. In insidious forms, it lurks woven into the very fabric of society. Poverty, after all, entails a host of risk factors — child maltreatment, drug abuse, crime, unemployment, bad nutrition, inadequate health care — that have been linked to various physical and mental illnesses.
Numerous languages characterize 'social pain', the feelings resulting from social estrangement, with words typically reserved for describing physical pain 'broken heart', 'broken bones' and perhaps for good reason. It has been suggested that, in mammalian species, the social-attachment system borrowed the computations of the pain system to prevent the potentially harmful consequences of social separation. Mounting evidence from the animal lesion and human neuroimaging literatures suggests that physical and social pain overlap in their underlying neural circuitry and computational processes.
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