Quarantines during the covid pandemic, such as closing schools, canceling sports activities and mandatory stay at home, caused teenagers' brains to age prematurely by as much as four years, scientists from the University of Washington have found.

A new study, published in the journal "Proceedings of the National Academy of Sciences", is further evidence that disruptions in daily routines can contribute to the development of behavioral problems, the rise of eating disorders and the development of anxiety and depression in adolescent girls and boys, reports NBC.

Scientists at the university's Institute for Brain Research and Science began the study using magnetic resonance imaging back in 2018 to determine how the brain structure of 160 Seattle-area teenagers developed over time. The study participants, almost equal numbers of boys and girls, were between the ages of 9 and 19 at the start of the study.

Research leader Patricia Kuhl, co-director of the Institute, said they were unable to follow up on brain scans until 2021 after the 2020 Covid lockdown began, so they shifted the focus of the study to find out how isolation affected on the brain structure of adolescents.

By measuring the thickness of the cerebral cortex – the outer layer of brain tissue that controls its higher-level functions such as judgment and decision-making – they found that teenage boys' brains aged prematurely – by 1,4 years, while brain scans of girls showed accelerated aging of as much as 4,2 years.

The cerebral cortex naturally thins as we age. And chronic stress can cause similar changes in the brain. But in the three-year period between the first scan and the follow-up, the cerebral cortex thinned out in the teenagers much more than the researchers expected.

"As we age, thinning of the cortex is associated with less time for rapid information processing, less flexible thinking, and all the other problems we associate with aging." "Overall, we saw this accelerated aging in all the teenagers who participated in the study," Kuhl said.

Brain aging is more pronounced in teenage girls

Brain aging was more pronounced in teenage girls. The scans showed that the thinning was widespread throughout the girls' brains, occurring in 30 regions in both hemispheres and in all lobes. In the male brain, the thinning was limited to just two regions, both in the occipital lobe, which affect distance and depth perception, face recognition and memory.

The greater impact on girls may be due to differences in the importance of social interaction for girls compared to boys, according to Kuhl. Boys gather for sports and physical activity, and adolescent girls tend to rely on personal relationships for emotional support and identity development.

"When girls and women are stressed, there's a natural response to come together and talk about it, when oxytocin and other feel-good neurotransmitters are released," said Dr. Ellen Rom, chief of adolescent medicine at Cleveland Clinic. who did not participate in the research.

Are there long-term risks to 'pandemic brains'?

The research does not indicate that quarantines caused changes in the brain. Namely, mental health disorders were on the rise among children even before the Covid pandemic. But the study suggests that thinning of the cortex may be linked to increased anxiety, depression and other behavioral disorders.

Another brain scan study conducted in 2022 at Stanford University showed similar changes in cortical brain thickness in teenagers during the restrictions in the covid pandemic. The Stanford researchers compared the stress and disruption caused by the pandemic to childhood traumas such as violence, neglect and family dysfunction.

Kuhl points out that the pandemic was a traumatic time for everyone, especially young people who experience intense changes in their emotional and behavioral development during that time of their lives. The isolation had an even more damaging effect on their emotional health.

"The pandemic was dramatic and unexpected, in some ways dramatic and devastating not only for physical but also for mental health," Kuhl concluded.