Impact of the pandemic on adolescent brain development: a comparative study

A recent study from the University of Washington, published in the Proceedings of the National Academy of Sciences, reveals significant differences in brain development between adolescent girls and boys following coronavirus-related lockdowns. The research focused on cortical thinning, a normal part of brain maturation in which the brain sheds excess synapses and shrinks its outer layer.

This process, which usually begins in late childhood or early adolescence, is known to improve the efficiency of the brain as it matures. However, stress can accelerate this thinning, which is often associated with increased risk of mental health problems such as anxiety and depression.

Data collected in 2021, as pandemic restrictions eased, indicated that both sexes experienced rapid cortical thinning during lockdowns. However, the progression in girls was significantly faster, averaging 4.2 years above the expected rate, compared with 1.4 years in boys.

Patricia K. Kuhl, a co-author of the study and director of the Institute for Learning and Brain Sciences at the University of Washington, noted that this accelerated development in girls may be linked to the heightened social isolation experienced during the pandemic. Adolescent girls, who often rely more on social interactions for emotional support, have been disproportionately affected by the lockdown measures.

The study began with a sample of 160 children and adolescents in 2018 and aimed to track typical brain changes during adolescence. However, the pandemic interrupted follow-up data collection planned for 2020. By 2021, when testing resumed, researchers were presented with a unique opportunity to observe the impacts of prolonged stress on brain development, making this study a natural experiment of its time.

While the findings are surprising, the researchers caution against interpreting accelerated cortical thinning as harmful. Ronald E. Dahl of the University of California, Berkeley, who was not involved in the study, emphasizes that thinning is a sign of brain maturation, not damage. The importance of these findings lies in their contribution to understanding how significant stressors like a pandemic can affect developmental trajectories.

The findings also highlight the importance of considering gender-specific impacts when assessing the consequences of global crises on youth development. As the world continues to navigate the aftermath of the pandemic, findings like these highlight the need for tailored strategies to support young people’s mental and emotional well-being.