Teenage brains have aged faster than normal during the pandemic, scientists have found.
An adolescent’s brain changes as the person enters adulthood, with some regions becoming larger and more developed.
But in children who have been subjected to extreme stress such as violence, abuse or neglect this process happens faster than normal.
Evidence from Stanford University scientists who performed brain scans on 163 children before and after the pandemic now shows that this process also occurred in adolescents during the Covid pandemic.
“We already know from global research that the pandemic has negatively impacted the mental health of young people, but we didn’t know what, if anything, it was physically doing to their brains,” said Professor Ian Gotlib, the study’s lead author.
During puberty and early adolescence, adolescent brains change with increased growth of the hippocampus and amygdala, two areas of the brain that control access to certain memories and also modulate emotions.
It is unclear whether the changes from the pandemic can be reversed
At the same time, the tissues of the cortex — an area involved in “executive functioning” — become thinner.
Prof Gotlib said that, until now, such accelerated changes in ‘brain age’ have only appeared in children who have experienced ‘chronic adversity’.
But it’s unclear what the long-term ramifications of these physiological changes in the brain are, and whether the changes from the pandemic can be reversed.
“If their brains stay permanently older than their chronological age, it’s not clear what the outcomes will be in the future,” said Prof. Gotlib.
“For a 70- or 80-year-old, you’d expect some cognitive and memory problems based on changes in the brain, but what does it mean for a 16-year-old if their brain is aging prematurely?”
Originally, explained Prof. Gotlib, his study was not designed to examine the impact of Covid-19 on brain structure.
Before the pandemic, his lab recruited a group of children and adolescents from across the San Francisco Bay Area to participate in a long-term study of depression during puberty.
But the pandemic cut that short and caused the study to be a year late when the scan resumed and that reset the whole study.
“Compared to adolescents evaluated before the pandemic, adolescents evaluated after the pandemic disruption not only had more severe internalizing mental health problems, but also had reduced cortical thickness, larger hippocampal and amygdala volume, and a ‘older brain age,’ said Prof. Gotlib.
The findings could have “important implications” for future studies
Professor Gotlib said the findings could have ‘major implications’ for other studies traversing the pandemic.
If young people who experienced the pandemic show accelerated development in their brains, scientists will need to account for that “abnormal” growth rate in any future research involving this generation.
“The pandemic is a global phenomenon: there is no one who hasn’t experienced it. There is no real control group,” he said.
Dr Jonas Miller, co-author of the study, said the findings could also have “serious consequences” for an entire generation of teenagers later in life.
Dr Miller, now an assistant professor of psychological sciences at the University of Connecticut, added: ‘Adolescence is already a time of rapid reorganization in the brain, and it’s already linked to increased rates of mental health problems, depression and risky behaviors.
“Now there’s this global event happening where everyone is experiencing some kind of adversity in the form of disruption to their daily routines – so it might be the case that the brains of kids who are 16 or 17 today are not comparable to those of their counterparts just a few years ago.”
The study is published in the journal Biological Psychiatry.