Scientists are racing to unravel the pandemic’s toll on kids’ brains

Gabriel was always an “angsty” child, his mother, Camille, remembers.

As a toddler, he was bright and curious — by 9 months he was intuitive enough to test out the strength of a cardboard box before climbing onto it. But he cried easily and was quick to anger. During fits, he’d swing his head back so violently that Camille considered buying him a helmet.

Camille didn’t understand his emotional outbursts, so when she heard about a study being done on stress and its biological and social roots in kids Gabriel’s age, she enrolled him. For the past 12 years or so, Gabriel, now 15, has visited the University of Washington for a battery of biological and psychological tests. Just before the pandemic, researchers scanned his brain using a magnetic resonance imaging machine. (The Seattle Times is only using Camille and Gabriel’s first names to protect their privacy.)

The researchers studying Gabriel and hundreds of other Puget Sound-area families knew that early life stress can have long-term consequences for mental health, which in turn can have profound effects on a child’s ability to learn in school. But what, exactly, happens to kids’ brains?

Answering that question became even more urgent when the pandemic hit, and so many children and teens were suddenly plagued by stress. Adolescents are generally more prone to anxiety and depression, but an unusually high number — more than half — were reporting these symptoms by about six months into the pandemic, the researchers found. Their latest findings on depression and anxiety, published this month, are a dire signal that the pandemic’s toll is steep, and they hold lessons for parents and teachers navigating an unpredictable path back to in-person learning.

Among the timely solutions the researchers have identified: a structured daily routine and limited passive screen time during the pandemic protects kids against depression and anxiety. Research is clear on the link between mental health and academics. Kids struggling with fears or having trouble regulating their emotions are more likely to experience challenges in school. The researchers’ work may prove invaluable to families — but also to teachers, who are rushing to understand how the pandemic might affect children’s learning and academic success.

At the start of the pandemic, the news was all bad, all the time. George Floyd was murdered by police, and social uprisings ensued. Schools were closed, and friends and teachers — typical buffers against the consequences of stress — all but disappeared.

Given what they knew from their other studies, the researchers were particularly concerned about children who had experienced early life stress and those suddenly thrown into extreme circumstances. Those whose parents lost jobs. Whose loved ones fell sick — or died. They might be the ones with the most trouble bouncing back, the researchers predicted.

The pandemic threatened to confound their ongoing research, but it also put them in a unique position to study how the public health crisis changed the course of children’s development and mental health.

“When we see changes in behavior or mental health, we know something is changing in the brain,” said Katie McLaughlin, of Harvard, who is leading the research with Liliana Lengua and Andrew Meltzoff of UW.

The links between stress and depression, anxiety and behavioral problems were stronger among teens than younger kids, the researchers found, suggesting that teenagers may be among the most vulnerable to the pandemic’s effects.

Scientists don’t yet know if the pandemic has altered children’s brains because it takes a long time to see how environmental factors alter the trajectory of a child’s brain development, said Bonnie Nagel, a psychiatry and behavioral neuroscience professor at Oregon Health & Science University. Nagel is not involved in Lengua and McLaughlin’s work, but is part of a national consortium of 21 research sites that has for years been following almost 12,000 adolescents. The study, called the ABCD study, is the largest of its kind to map brain development during adolescence.

But even without a complete picture, the urgency is clear.

“As kids begin to return to school, what do we see about patterns of recovery for kids who did develop symptoms during the pandemic? … Will these symptoms persist over time?” McLaughlin said. “We’re going to need to begin grappling with, what do we do [to help them]?”

‘Revolutionary time’

Adolescence is a difficult developmental period, a time when kids test boundaries and itch to separate themselves from their parents. Their brains are also remodeling, and with that comes a greater ability to solve problems, think abstractly and form their identity.

It’s the second of three major “revolutionary times” for brain development, said Meltzoff, a professor of psychology and co-director of UW’s Institute for Learning & Brain Sciences, better known as I-LABS. The first of those times is ages birth-3, when the brain is booting up, the last being aging, when it’s winding down.

All sorts of things are heightened as youth careen, clumsily, from childhood toward adulthood. They’re more sensitive to how friends perceive them. They desperately want to feel they belong. Socializing — playing sports, joining clubs — is an incredibly important part of their lives.

With the pandemic, Meltzoff said, “all of that is ripped away from adolescents at a very vulnerable time. … Any time when there’s this radical change in the brain and thinking about their own identity, these disruptions to routine can deeply affect kids.”

When the pandemic hit, Meltzoff called McLaughlin, a former co-worker at the UW. Meltzoff, McLaughlin and Lengua had been following hundreds of Seattle-area families for years. Stress and its relationship to mental health outcomes was a significant area of scientific inquiry. They were searching for biological clues that tied the two together.

Having hundreds of families to call on was a plum situation for those looking to track the pandemic’s effects.

They got to work.

Neuroimaging was a longshot because funding had dried up — brain scanning is expensive — and like most scientific labs, theirs shuttered during lockdown. But surveying is cheap. By April 2020 they’d tracked down about 225 of the 300 kids from their longitudinal studies who were now 7-10 years old and 13-15, and sent them questionnaires about their mental health, coping strategies and exposure to stress.

Before the pandemic, about 30% of the youths had symptoms of anxiety or depression, and 17% had behavioral issues like aggression, said McLaughlin, professor of psychology at Harvard. But by April 2020, and again in fall 2020, they found, both of those numbers jumped to above 56%. The strongest predictor of whether mental health problems increased in an individual child was the degree to which they experienced pandemic-related stress, they found. And the more stressors a child experienced, the more likely they were to experience mental health problems.

This fits with research on natural disasters and terrorist attacks, which shows that wide-scale community stressors are tied to a rise in mental health concerns. What’s surprising, McLaughlin said, is the magnitude of the rise during the pandemic.

An extensive body of evidence from natural disasters also offers some good news. Most kids are resilient. They recover quickly, and don’t need serious mental health interventions.

But the researchers quickly realized youths’ experiences were enormously variable.

“We have some preliminary analyses showing … lower [family] income before COVID predicted higher rates of COVID-related stress and challenges. And that was related to both moms’ mental health and children’s mental health,” said Lengua, professor of psychology and director of UW’s Center for Child and Family Well-being.

This fits with a pernicious pandemic trend. For kids who were already struggling — they had family conflict or mental health concerns — “the pandemic clearly exacerbated those,” issues, Lengua said. “And so those children are more vulnerable [to] longer-term effects.”

Their findings, the researchers say, signal who may need the most help bouncing back when school starts.

Planning ahead

Gabriel remembers small details about the day scientists scanned his brain: the ceramic tiles and dim lighting in the near-empty MRI room. The panicked feeling that he’d forgotten to remove something metal from his pockets.

Nearly every year around his birthday, starting at age 3, Gabriel would don an electrode cap, complete surveys or sit for observation as researchers asked him to complete tasks or undergo a scan. After he underwent an MRI in seventh grade, he finally asked his mom: “Why do we do this?”

Lying still, tucked away inside the whirring megamachine, he suddenly wondered. His mom has her reasons. She was genuinely curious about the study’s premise. And Camille, who is Black, was also tired of the cliche or perception in research studies that Black people are low-income — as a middle-class woman, she thought her family’s participation might help change the narrative.

The pandemic gave Gabriel his own drive to keep participating; the consequences of stress were suddenly more visible. During angry outbursts as a kid, “everything went dark,” he says. But during the pandemic, his feelings of paranoia, uncertainty and grief became so unmanageable that he had a more serious meltdown. His family made the difficult decision to send him to live with relatives in Atlanta for a few weeks to take a break from it all.

When researchers asked if he’d participate in surveys about his experience, he was glad to help. “I really felt like I was doing nothing with my life and it was going to go nowhere, so knowing I was doing that at least felt like I was doing something” to be proud of, he said.

If the researchers can figure out why some children came away relatively unscathed, and others didn’t, they might find strategies the mental health community, but also families and educators, could use to support kids if disaster happens again.

They might also find ways to help kids recover now.

This month, the research team reported in the academic journal PLOS ONE what seems to help: Kids who get a full night’s sleep did better than those who didn’t. Limiting exposure to pandemic-related news, especially among 7- to 10-year-olds, was also helpful. Keeping kids from scrolling through their phones or mindlessly watching TV — so-called “passive” screen time — was also associated with better mental health outcomes. So was maintaining a daily routine, a difficult prospect for many families during a chaotic year marked by school closures.

Some of these tactics seem obvious, Meltzoff admits. But “there are a lot of things you can imagine doing or recommending, and really we have just a few that show very strong, significant, statistical effects.”

Other experts say they’re pleased to see a focus on solutions. “I like [the team’s] paper because it is focused on, how do we intervene, or how do we prevent?” said BJ Casey, a professor of psychology at Yale University and a principal investigator on the ABCD Study. “We need a paradigm shift in prevention and providing youth with the tools they need, even before they have symptoms.”

More data could help researchers and educators predict which kids might also struggle academically — and help scientists in their pursuit of the pandemic’s fingerprints on children’s biology.

Meanwhile, Nagel and most of the other ABCD consortium member labs have resumed their research in-person. After months of delays during the pandemic, they’re bringing 13- and 14-year-old participants in for MRI scans again. The ABCD project’s data is publicly available to other scientists, which could allow researchers like McLaughlin and her colleagues to soon answer the questions they might not be able to tackle alone.

They’re racing to find out.

“At the end of the day, there won’t be a paper published [titled] ‘The Pandemic’s Effect on the Developing Brain,’” said Nagel, a principal investigator on the ABCD study. There was no universal experience — every child’s story was unique.

But short of that, she said, the work could soon offer much-needed answers to how youth were affected by all the little things that fell apart in the pandemic’s wake.