According to a study conducted by the University of Washington (USA) and published on September 9 in the multidisciplinary journal Proceedings of the National Academy of Sciences, the brains of teenage girls who experienced the Covid-19 pandemic show signs of “premature aging.”
The study was carried out by measuring cortical thinning, a process that begins in late childhood or early adolescence. Scientists consider this process as the brain’s way of reorganizing itself during maturation, enhancing its operational efficiency. However, this process can accelerate under stress, and rapid cortical thinning is often associated with depression and anxiety.
Image showing cortical thinning in female adolescents compared to male adolescents. (Photo: Institute for Learning and Brain Sciences, University of Washington).
The research team began surveying a group of 160 children and adolescents with the aim of describing typical changes during the teenage years. The initial brain imaging scans to collect necessary data were conducted in 2018 when the subjects were aged 9-17. However, the Covid-19 pandemic in 2020 caused the second measurement to be postponed.
By 2021, after lockdowns and travel restrictions due to the pandemic began to lift, all study subjects had no longer been under prolonged stress from the pandemic, and about 130 participants returned for the second round of research. This allowed the study to compare data collected before and after the pandemic regarding the brain development of this group. Dr. Neva Corrigan, the lead researcher, suggested that this created a “natural experiment.“
The results indicated that both males and females in their teenage years experienced rapid cortical thinning during both the pre- and post-lockdown periods due to the pandemic. However, this effect was significantly more pronounced in females. The rate of cortical thinning in females increased more rapidly, with an average early aging rate of 4.2 years, compared to 1.4 years for males.
According to Dr. Patricia K. Kuhl, head of the Brain Science Institute at the University of Washington and one of the study’s authors, the results show that aging effects occur throughout the brain – in all lobes of both hemispheres. Dr. Kuhl believes that this change is due to social isolation caused by the Covid-19 pandemic, and that females were more affected because they rely more on social interaction, such as talking with peers to relieve stress.
The researchers noted that these results will contribute to studies on deteriorating health among youth during the pandemic and emphasize that rapid cortical thinning is not necessarily a sign of brain damage. Dr. Ronald E. Dahl, director of the Institute for Human Development at the University of California, Berkeley, and not involved in the study, stated that thinning cortex does not necessarily indicate a problem but may signify a sign of maturation.
Although some previous brain studies have found that pandemic-related stress accelerated cortical thinning, none have compared such changes between females and males in their teenage years.
However, researchers are still unable to determine whether these changes are permanent or if the brain development of adolescents will return to normal levels once social interactions are restored.
