Surviving the COVID-19 pandemic may have caused teenagers’ brains to mature beyond their years.
From online learning and social isolation to economic hardship and rising death tolls, the past few years have been tough for young people. For teenagers, the pandemic and its many side effects occurred during a crucial period of brain development.
Now, a small study comparing brain scans of young adults before and after 2020 shows that the brains of teenagers who survived the pandemic look about three years older than expected scientists say.
This study, published on December 1 in Biological Psychiatry: Global Open Science is the first to examine the impact of the pandemic on brain aging.
The findings show that “the pandemic wasn’t just bad for adolescent mental health,” says Ian Gottlieb, a clinical neuroscientist at Stanford University. “It seems to have changed their brains as well.”
The study cannot link these brain changes to poor mental health during the pandemic. But “we know there’s a relationship between adversity and the brain trying to adapt to what it’s been given,” says Beatrice Luna, a cognitive neuroscientist at the University of Pittsburgh who was not involved in the study. “I think this is a very important study that allows us to look at that.”
The roots of this research go back nearly a decade, when Gottlieb and his colleagues launched a project in the Gulf of California to study depression in teenagers. The researchers collected information about the mental health of the children who participated in the study and conducted MRI scans of their brains.
Blocking orders in the spring of 2020 forced the researchers to halt the project. When they restarted a year later, Gottlieb worried that the stress of the pandemic threatened to distort their results.
It found that children returning to the study after a year of life during the pandemic reported higher rates of anxiety and depression than their peers by 2020. So the team decided to compare brain scans taken before the pandemic began. with scans taken between October 2020 and March 2022.
The researchers looked at differences in 64 scans from each group, matched for sex and age of children, with an average age of about 16 years for each group.
The results were “spectacular,” says Gottlieb.
The adolescent brain naturally goes through a maturation process that results in thickening of the hippocampus, an area associated with memory and concentration, and the amygdala, which regulates emotional processing. At the same time, the cortex—the area that regulates emotional functioning—begins to thin.
Brain scans showed that this maturation process happened faster in teenagers who survived the pandemic. Gottlieb says their brains appeared to be three to four years older than the brains of teenagers scanned before the pandemic began.
It is not known exactly what part of the pandemic could shape the brains of teenagers. But “this study shows that the pandemic has had a significant impact on brain maturation,” says Joan Luby, a child psychiatrist at Washington University School of Medicine in St. Louis, who was not involved in the study.
Gottlieb suspects stress is to blame. Previous research has shown that abuse or neglect can lead to accelerated brain maturation in children. Given that the mental health of teenagers has deteriorated dramatically during the pandemic“it’s not a big leap” to think that stressful conditions could also have shaped brain development in his study cohort, Gottlieb says.
But the questions of what caused the changes and what consequences they may have remain open. Rudolf Uger, a neuroscientist at Dalhousie University in Halifax, Canada, notes that other factors, such as more screen time due to online learning, may be at play. And he cautions that future research may not confirm this study’s findings.
And it is not clear whether the accelerated aging of the brain affected the health of the teenagers, or whether problems will arise later in life. Although researchers can’t say for sure, “if your brain is aging prematurely, it’s generally not a good thing,” Luby says.
Either way, ensuring people have access to mental health services will be critical to helping children during the pandemic, Gottlieb says.
“These kids are hurting,” he says. “We need to take this seriously and make sure we offer them treatment.”
