Constance Bannister Corp / Getty

When Darnell Mitchell recently watched Die Hard, the classic 1988 action film starring Bruce Willis, he couldn’t stop grimacing at his television screen, but not at the violent scenes you might expect. Mitchell had seen the movie before, several years ago, but this time felt different. The characters’ actions seemed, somehow, cringier.

“I was like, Why am I reacting this way? What’s happening?” Mitchell recounted to me recently. “And then I realized: Oh, I’m actually reacting to each time they touch their face.”

Mitchell, a stylist, lives in New York City, the epicenter of the coronavirus pandemic in the United States. Like many Americans sequestered in their home, Mitchell has spent the past month heeding the dos and don’ts for protecting himself from the virus, including the advice to avoid touching your face. “I was like, Bruce, get it together. What’s happening? Did you not watch the news?” Mitchell said. “Now almost every single TV show or movie makes me slightly uncomfortable when I watch it, because the entire time, I’m thinking about it.”

Sometime in the past few months, as social-distancing measures tightened across the country, many of us, like Mitchell, discovered new, pandemic-specific tics. Keyla Eusebio, a college-admissions officer in Rhode Island, told me that she first felt them in mid-March. Steven Kast, a computer-science student in Ohio, noticed them in early April. The sight of two people shaking hands. Someone touching their uncovered face. A group of people hanging out less than six feet apart. Mundane behaviors they would not have thought twice about previously now trigger sudden, visceral reactions—of discomfort or disgust, fear or indignation—whether they’re occurring on-screen or in real life. It almost seems as if the response to the pandemic has somehow, quietly and without warning, rewired our brains.

While these tendencies are new, the mechanism behind them is not. The cringes and shudders and yikes are products of one of our most primitive cognitive processes: learning, through experience, to associate one thing with another. As we moved through the motions of life during a pandemic, keeping our hands off our faces and humming “Happy Birthday” at the sink, our brains took these behaviors and gave them new meanings.

“Most things associated with COVID-19 are bad and even lethal, so it’s not surprising that negative emotions are becoming associated with the objects or behaviors that are associated with COVID-19,” Jana Schaich Borg, a neuroscientist at Duke University who studies social behavior and cognition, told me in an email.

We’ve been conditioned, in other words. “When a learned association is both strong and unconscious,” Schaich Borg said, “it can feel like an innate reflex.”

Building these connections doesn’t take long, and they can be especially sticky. A single bout of food poisoning, for example, might put you off that restaurant for good. To this day, Schaich Borg can’t bring herself to eat Cheez-Its, because she had them just before becoming horribly seasick on a ferry when she was little. The pandemic has presented an extreme version of this, a slow burn of stimuli that has produced a collective aversion to previously innocuous behaviors and settings. We are all on the ferry together, full of Cheez-Its and seasick.

Feeling some kind of way about once-commonplace and -ordinary interactions, whether that’s fear or disgust, might be beneficial, though. Fear, after all, is a survival mechanism that protects us from dangerous or deadly situations. Some scientists believe that disgust works in a similar way, an evolutionary impulse meant to ward us off from coming into close contact with harmful things, including invisible contaminants that could make us ill.

Some people told me that they felt angry when they saw people in their neighborhood ignoring social-distancing practices, potentially putting others at risk. The evolutionary benefits of moral outrage are still debated, Schaich Borg said, but there could be something to it during a pandemic: “Some have argued we expend energy to identify or punish free-riders and those who harm society because doing so signals we can be trusted, which in turn motivates people to cooperate with us.”

Our new reflexes, which might have seemed irrational a month ago, are quite acceptable now, even useful—not for watching Die Hard, but for navigating the outside world. “If our current understanding of how the virus is transmitted is accurate, we will be less likely to catch the virus if we are averse to touching our face and if we avoid groups of people,” Schaich Borg said.

Context matters, of course. Someday, when the country has moved beyond the worst of the pandemic and some sense of normalcy reemerges, these associations may not be useful anymore, and we will have to rediscover our old associations. “Then it should not only be normal but desirable to be with others and socialize,” says Stefan Hofmann, a psychologist at Boston University’s Center for Anxiety and Related Disorders. “And until that point is reached, we need to stay away from each other.”

It is difficult, for now, to predict when that reality will occur, and to imagine how, after enduring potentially months of strict social-distancing measures, we might unlearn these little tics, or which vestiges of these times will remain. Some people, especially those who might have already had obsessive-compulsive tendencies, might become germaphobes, says Steven Taylor, a psychologist at the University of British Columbia and the author of The Psychology of Pandemics. But “for most people, this will be a short-term germ aversion,” he adds. “And then in the weeks to months afterward, life will sort of return to whatever normal is waiting for us.” Just as we did during the pandemic, we will come to make new associations, with positive responses, that might very well override the old ones.

In the meantime, we must grapple with another pandemic-specific feeling: the exacerbated sense that the days before the coronavirus swept across the country—the “Before Time,” as many have taken to calling it—feel like a bygone era. “I have to remind myself that there actually was a point that it was safe to go to parties and it was safe to hold hands and hug people and see your loved ones,” said Eusebio, the college-admissions officer. “It’s shocking how I see hugging people as a thing that we’d frown upon right now, where only months ago that was a normal thing to be doing.”

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.