Teenage girls who experienced coronavirus lockdowns experienced faster brain ageing than boys, data has found, suggesting that social restrictions have had a disproportionate effect on girls.
MRI scans found evidence of premature brain ageing in both men and women, with girls’ brains appearing on average 4.2 years older than expected after lockdown, and boys’ brains appearing 1.4 years older.
It is unclear whether these changes will have negative effects, but the findings have raised concerns that they could affect young people’s mental health and ability to learn.
“I was shocked by the data – the differences were so dramatic,” said Professor Patricia Kuhl, co-director of the Institute for Learning and Brain Sciences at the University of Washington in Seattle.
The researchers collected MRI scans of 160 people between the ages of 9 and 17 in 2018 and used them to build a model of how the brain’s cortex typically thins during school age. Some cortical thinning is natural and an important part of the brain’s maturation and specialization during adolescence.
The team re-examined the same cohort after lockdown in 2021 and 2022, collecting further MRI scans from people aged 12 to 16. Compared to pre-pandemic brain development, they found signs of accelerated cortical thinning in one area of the boys’ brains and 30 areas of the girls’ brains, across both hemispheres and all lobes.
Other researchers have linked premature brain aging to the pandemic, but the latest study Proceedings of the National Academy of Scienceswas the first to reveal clear differences between boys and girls.
Both men and women showed signs of accelerated ageing in areas of the brain associated with vision, which may affect face recognition, but the brain changes in women were more widespread, affecting areas that underpin social cognition, such as processing emotions, interpreting facial expressions and understanding language, which the researchers say are crucial for communication.
Kuhl believes this difference reflects girls’ greater reliance on social groups and interactions. “Girls chat endlessly and share their feelings,” she says. “Girls rely more on social groups and interactions. [than boys] Active social participation is important for children’s well-being and healthy neurological, physical and emotional development.”
Although more research is needed to determine whether brain aging affects cognitive abilities, Kuhl noted that early cortical thinning has been associated with early life adversity and increased risk of neuropsychiatric disorders. Cortical thinning is essential for brain specialization, but it could lead to a loss of cognitive flexibility and impact learning.
Kuhl said the findings are a “reminder of the vulnerability of teenagers” and suggested parents talk to their teens about their experiences during the pandemic. “Invite them for coffee or tea or a walk, and open up a conversation,” Kuhl said. “Do whatever it takes to get them to open up.”
“Although the pandemic is largely over, it’s important to recognize that the effects of pandemic stress are still felt in children and adolescents,” said Ian Gottleib, a psychology professor at Stanford University who has reported similar brain changes. “Making sure that young people have access to mental health support is perhaps more important than ever.”
“This adds to our understanding that the COVID-19 pandemic has accelerated changes in the brains of young people,” said Dr Lina van Drunen, a researcher at Leiden University in the Netherlands who reported the findings. Similar brain changes in adolescentsIt is now important to identify the specific factors behind premature ageing and understand its long-term consequences, she added.
