A recent study published by the Proceedings of the National Academy of Sciences suggests teenage brains are maturing faster than usual as a side effect of the COVID-19 pandemic.
Researchers evaluated the cerebral cortex of teens pre- and post-pandemic, finding differences in the a four-millimeter outer layer of the brain responsible for memory, reasoning and problem-solving. They found accelerated thinning equating to about four years of extra aging in girls, compared to just over one year in teen boys.
“These findings are kind of startling if you just look at the headline," said clinical psychologist Kyle Boerke, director of behavioral sciences at OSF HealthCare in Bloomington.
Boerke noted the study's limitations, including a small sample size.
"But I think it's a great conversation point that we're starting to look at what the true impact of the pandemic was," he said. "From my perspective, more important than figuring out what has occurred is that we start to think about what we need to do in the future."
According to Boerke, the COVID-19 virus is likely not the root cause of advanced maturation; it was the lack of social activity.
“The thinning areas that were noticed the most had a lot to do with the processing of emotions, empathy and even language centers,” he said. “I think that speaks a lot to what part of the pandemic was responsible for some of the results of the study.”
The pandemic did not push people into complete social isolation. In fact, teens' relative fluency with social media and online communication provided sources of interaction when face-to-face conversations were not an option.
“I think the problem is [that] as the pandemic waned and the ability for more in-person social interactions came to fruition, they’d already gotten set in their ways of using technology and social media for their social interactions and the in-person interactions didn't come back,” Boerke said.
In addition to physical maturation during puberty, teenagers experience rapid changes related to social-emotional growth affecting their brains.
"They're getting to individuation," Boerke said, "where they're primary source of social interaction had been their parents, and it's shifting over to their peers."
Brain development during adolescence is "already a very complicated place," said Boerke, even without a world-shifting pandemic.
"Now you add in the pandemic and the reduction in what was normal for them and it adds extra stressors to the adolescent brain that's such a fragile place to begin with," he said.
The brain processes two-dimensional social interactions differently than three-dimensional ones.
“I think that’s where we’re seeing some of this come from,” Boerke said, "not to mention stress. We know that cortical thinning comes a lot from stress. All of us, whether we're adolescents or adults—we were all under a lot of stress during the peak of the pandemic."
The stark gender gap demonstrated in the study could be attributed to differences in social interactions between males and females, the latter typically more dependent on one-on-one socialization.
What does it mean?
Boerke cautions people from jumping to the conclusion that teens are experiencing negative outcomes due to cortical thinning. These are not "problems" so much as they are observations, he said. The cerebral cortex contains billions of neurons. The study does not assess how many neurons were impacted, measuring cortical thickness without noting the density of neurons.
"It's something that's of note and I'm glad to have the conversation, but you can't generalize it to say we have a big skills deficit or impairment because of this," said Boerke.
Preventing such deficits relies on ensuring teens get face-to-face, in-person contact. Knowing this, Boerke said guidelines for preserving social interaction should be a priority if another pandemic were to occur.
"It begs a conversation about social media as well," Boerke said. "Social media was a tool to continue to have social interactions. The problem was, it became what we relied upon. That's where it can start to be damaging."
The role of social media, Boerke said, should be to facilitate in-person interaction.
"Unfortunately it's moved to where social media is the social interaction," he said.
Not just teens?
While teenagers were the focus of the study, they are not the only age group to be affected by the limited in-person interaction, irrespective of brain thinning.
“That year of kindergarten for some people truly is the first foray into structured social interactions with peers,” Boerke said. “We do have kiddos that didn’t get to have that very formative year of social interaction. I think we’re going to have some skills catch-up to be doing with some of these younger ages that were in those truly critical stages of life during the pandemic.”
