Earlier this year, when the start-up where Danielle works decided to reopen its Philadelphia office, the project manager was so anxious at the prospect that she sought the help of a therapist for the first time.

“I started to get really nervous and unsure,” said Danielle, 39, who lives in the city and asked that her last name not be used over worries that it could impact her career. “I’ve been remote this whole year. …. I just have this fear — what if we reopen and we become the next India?” referring to the devastating outbreak there.

Even though an end to the pandemic seems to be in sight as vaccinations increase and restrictions ease, many workers are anxious about returning to the office — and in-person interactions — after more than a year away. And that anxiety might be short-circuiting the brain’s ability to cope.

“We’ve seen one another as threats for a year,” said Michelle Pearce, a clinical psychologist and director of the Integrative Health and Wellness Certificate Program at the University of Maryland. “That doesn’t disappear overnight, even after you get a shot in the arm. We need to retrain our brains.”

A survey released last month of 500 U.S. human resource managers found that they think employees are struggling with returning to work, with 37% of managers saying that most of their workers felt stressed about reopening and 31% saying employees were anxious about it, according to Koa Health, a digital mental health-care provider.

Many workers, of course, have had little choice but to hold the front lines of hospitals, grocery stores, and other essential industries, stress or no stress. But for remote-laboring professionals, all this angst may well be in their heads. That is, literally, the result of potential pandemic-induced changes to brains, neuroscientists said.

Normally, the amygdala, the region that processes emotions, signals when a potential threat is present. Usually, the signal is tied to a negative emotion such as fear or anger, explained Crystal Reeck, an assistant professor at Temple University’s Fox School of Business who specializes in the psychology and neurology of decision making. That triggers a fight-or-flight response. “Think about it as an alarm system,” she said. “It helps draw your attention to a threat in the environment.”

Meanwhile, the prefrontal cortex, which is involved in decision making and social behavior, assesses the threat — for example, delivering a speech in public — and turns down the alarm bell, Reeck said, by reminding you that you are prepared.

» READ MORE: Easing workplace anxiety post-pandemic

Research has shown that anxious people tend to have a more active amygdala and less well-developed prefrontal cortex, hindering the regulation of the threat signal, Reeck said. “During anxiety, that loop is disrupted,” she said.

What does this have to do with workplace worries? Over the last year-plus, Reeck said, the amygdala may well have gotten rewired to learn new threats, such as someone coughing, or standing closer than six feet, or not wearing a mask. “That’s helped keep us safe when we were supposed to quarantine and maintain a social distance,” she said.

But now, as offices reopen and the Centers for Disease Control and Prevention says those who are fully vaccinated no longer need to wear masks, it may take some time to reset, Reeck said.

Consider the aftermath of the 1918 flu pandemic. According to Miami-area psychiatrist Arthur Bregman, who has researched the topic, many who lived through the earlier outbreak feared leaving their homes. They had what Bregman dubbed the Cave Syndrome, where people hunker down and are reluctant to leave home.

“Most people had chronic PTSD,” he said. Bregman anticipates the same kind of reaction this time around, as well. Already, he has anxious patients asking him to write notes excusing them from returning to the office, he said. “It’s not so easy to be isolated like we were and then go back to work. It’s not like an off or on switch.”

The American Psychological Association’s 2021 “Stress in America” online poll of 2,076 U.S. adults found that prolonged stress persists at elevated levels for many Americans, with 47% feeling anxiety in the previous two weeks.

When Danielle’s company decided to reopen one day a week in April, with plans to go four days a week by summer, the introvert deep down said her anxiety — that racing heart, those sweaty palms — rose each time she walked through the office doors, as if it were the first day of school. A lot of it was fear of the unknown.

For help, she turned to hypnotherapist Alexandra Janelli, who has a Philadelphia branch of Theta Spring Hypnosis. Over three sessions, totaling about $800, Janelli suggested, while Danielle was in a hypnotic state, ways to handle specific fears, such as coworkers who forget to pull up their masks. Janelli reminded her that she was fully vaccinated and that she could step back from the person. “Through hypnosis,” she said, “I help them build confidence and find their own solutions.”

Said Danielle: “I felt a huge difference. Everything Alexandra was saying was speaking to me.” When she starts to feel anxious, she said, she focuses on what she can control. “The anxiety goes down. It’s such a relief and help.”

Like many employers, Philadelphia law firm Hangley Aronchick Segal Pudlin & Schiller is studying reopening options. The firm is looking to balance the needs of the company and the concerns of individual employees, said real estate attorney David M. Scolnic, a shareholder and board member.

Based on a survey last year of its 100 employees, Hangley found that the top issue was getting to work, including the use of public transportation and the elevators to reach its offices on the 27th and 28th floors of One Logan Square. In conversations with employees, Scolnic said, “that concern is still there.”

The firm is also wrestling with whether to require vaccinations, how many days to ask employees to return to the office, when to reopen and so on. “It’s complicated,” Scolnic said. “You want to make sure employees are comfortable. Right now, we’re trying to listen very hard to what their concerns are.”

As employees emerge, they may experience low energy, low motivation, irritability, and difficulty concentrating, said Pearce, at the University of Maryland. “A lot of us are grieving,” she said. “We’ve all lost something, collectively and individually.”

According to David Rock, the CEO and cofounder of the global consultancy NeuroLeadership Institute, companies should take these mental health concerns seriously, creating not only physical protection but also psychological safety. Without the latter, he said, employees might get mired in anxiety and depression, hindering creativity or out-of-the-box thinking.

A company’s strongest lever, Rock added, is giving workers a sense of control, and that starts with choices about returning to offices. “Fundamentally, a lot of people are very anxious about going back into a world where 40% to 50% of people are not vaccinated,” he said. “What offsets that type of anxiety is a greater sense of control over work, of being treated fairly.”

When speech therapist Abby Stern went from fully remote to spending half her time at the preschool in Media where she works, she was extremely worried. Before the pandemic, Stern suffered from panic attacks caused by a fear of getting sick. The pandemic only exacerbated her anxiety, and the prospect of in-person encounters was one more stressor, causing her stomach to hurt and heart to race.

“I have kids sitting in my lap,” said Stern, who returned full time in February. “In the beginning, I was very nervous. My nightmare scenario was that the first day I get back, all the kids are going to be coughing, and two weeks later, half the staff will be sick.”

But Stern is working through it. Her supervisor, for instance, was OK with her initially wearing two masks all the time and eating lunch in her car. She also struggled a little with how much distance to maintain while making small talk with colleagues, but that, too, eased over time, especially after she got vaccinated.

Still, Stern said, “it always baffles me when people are not anxious. How can you not be worried about this?”

The Future of Work is produced with support from the William Penn Foundation and the Lenfest Institute for Journalism. Editorial content is created independently of the project’s donors.