Zoran Milich / Reuters

The more Donald Trump and Ted Cruz talk about denying Syrian refugees and undocumented immigrants entry into the United States, the more their poll numbers rise. On Monday, Trump went so far as to call for “a total and complete shutdown of Muslims entering the United States.” Meanwhile, protests have erupted on college campuses over discrimination as students feel isolated and unwelcome. The politics of exclusion have taken center stage in a national conversation—unfortunately, the pain of rejection may be all too real.

“Emotional pain can be as excruciating as physical pain,” wrote University of Toronto psychology professor Geoff MacDonald, in a chapter of the 2009 Cambridge Handbook of Personality Psychology titled “Social Pain and Hurt Feelings.” MacDonald is one of a growing number of researchers who believe the pain of hurt feelings may be as real and as serious as physical injury. That concept isn’t conventional wisdom or established scientific fact. Nevertheless, it is striking at a time when debate over free speech, political correctness, and who belongs in American society—and who doesn’t—has dominated the campaign trail and college campuses around the country.

Rejection plays a central role in that debate. Some conservatives have cheered Republican candidates for speaking their minds regardless of who takes offense. On college campuses, liberals and conservatives alike have protested the idea that universities should attach warning labels to subject matter that inflicts emotional pain. For many across the political spectrum, the underlying assumption is that hurt feelings are fairly trivial.

But what if Americans underestimate the toll of emotional trauma? Research suggests that emotional pain may be processed by the brain in some of the same ways that the brain reacts to the pain of a broken bone. In 2003, researchers at the University of California, Los Angeles published the results of an experiment designed to study social exclusion. Volunteers took part in an online game that mimicked the experience of tossing a ball. The same parts of the brain that are activated by physical pain lit up when participants felt excluded by other players.

“I don’t think anyone is going to confuse a stubbed toe with going through a breakup,” said Naomi Eisenberger, a UCLA psychology professor who helped conduct the experiment. “But emotional pain has been a kind of second-class citizen. I think we take physical pain a bit more seriously. Our work suggests that we should think seriously about the impact of emotional pain, too.”

Of course, not everyone reacts to exclusion the same way. Some people are more resilient. How people ultimately respond appears to hinge on a variety of factors, including their feelings toward the individual excluding them and perception of the situation. “There is a lot of variability in terms of how people respond to these strangers excluding them.  Some people are upset. Some could care less. It depends on their interpretation of events,” Eisenberger said.

Some people may even go numb. A 2006 study published in the Journal of Personality and Social Psychology found that participants were less sensitive to physical pain after being told they were likely to spend the rest of their lives alone. Researchers believe that numbness in the face of extreme emotional pain may occur because people go into a state of shock—just as they might after a severe physical injury.

“Social rejection can be really powerful,” said Ethan Kross, a University of Michigan professor who has studied the potential link between rejection and physical pain.

There is also evidence that psychological damage results when people feel excluded over long periods of time. “When people are ostracized day in and day out, their ability to regain a sense of belonging becomes depleted,” said Kip Williams, a Purdue University professor who studies the impact of being ignored and excluded. “Eventually, people become depressed, helpless, and alienated as a feeling of worthlessness sets in.”

Yet while rejection may hurt, there is likely a benefit to experiencing emotional pain. Physical pain tells us what to avoid in order to prevent serious injury. Hurt feelings deliver cues that may help us navigate social interaction. Research also suggests that people often seek out social connection in response to rejection. In other words, social ties may ultimately be strengthened after an episode of exclusion.

“Social exclusion hurts, but that’s not an automatic argument that nobody should ever hurt each other,” MacDonald said. “Pain transmits important information that helps us recognize what’s healthy and what’s not. When you get hurt, you reflect on that. Sometimes, that’s a sign that things need to change.”

Research helps to describe the extent of the pain, but it can’t determine how society should respond. Evidence of the impact of emotional pain can be marshaled in favor of calls to pay more attention to social injury and eliminate its triggers, or to support calls for individuals who feel the sting of rejection to find ways to cope and become more resilient. The pain, in either case, is very real.

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