A new study has found that during the period of social isolation and lockdown caused by the COVID-19 pandemic, girls’ brain aging accelerated beyond expectations and at a faster rate than boys.
The research report stated that due to the highly contagious nature of COVID-19, governments worldwide implemented restrictive measures including stay-at-home orders, maintaining social distance, and school closures. These restrictive measures had a significant negative impact on the mental health of adolescents, with females experiencing a greater impact compared to males.
Led by researchers at the University of Washington, the study was published in the Proceedings of the National Academy of Sciences on Monday, September 9. The research team utilized magnetic resonance imaging (MRI) technology to analyze the structural changes in the brains of 160 participants aged 9 to 17.
Senior author of the study, Patricia Kuhl, Joint Director of the Institute for Learning and Brain Sciences (I-LABS) at the University of Washington, stated in an article that the COVID-19 pandemic is not just a “health crisis” but has brought about profound changes in our lives, especially for adolescents.
The initial aim of the study was to examine the typical changes in brain structure during adolescence. As the brain matures, the cortex, the outer layer of the brain, naturally begins to thin, even in teenagers.
However, researchers noted that under “prolonged stress and adversity,” this thinning process accelerates, increasing the risk of disorders including anxiety and depression, particularly among females.
The first scan was conducted in 2018, with a planned second scan in 2020. However, the COVID-19 pandemic lockdown prevented the second scan from taking place, forcing researchers to wait an additional year.
In 2021, they finally obtained the results of the second MRI scan. At this point, the team observed a striking change in the participants.
The results of the 2021 scan revealed that after experiencing a prolonged period of social isolation following the pandemic, the brain cortex of post-pandemic participants thinned at an accelerated rate. Moreover, females showed a more severe aging pattern compared to males, with an average acceleration of 4.2 years for females and 1.4 years for males.
In other words, a girl who entered the study at the age of 11, after the pandemic lockdown and returning at 14, exhibited a brain that appeared similar to that of an 18-year-old girl.
It has been documented in numerous studies that prolonged stress or adversity can lead to accelerated brain maturation.
Dr. Ellen S. Rome, Director of Adolescent Medicine at the Cleveland Clinic, noted that adult women with anorexia nervosa show cortical atrophy or brain thinning related to starvation. She mentioned the increase in eating disorders cases during and post-pandemic and suggested future research to elucidate whether this study reflects an increase in eating disorders among girls during the pandemic or other factors.
The study revealed rapid thinning in various parts of the female brain, while males only showed thinning in the visual cortex, suggesting that developing girls may rely more on social interactions, gatherings, conversation, and emotional sharing opportunities.
However, the study has limitations. Dr. Max Wiznitzer, Professor of Pediatrics and Neurology at Case Western Reserve University School of Medicine, pointed out the lack of a true control group in the study, as everyone was affected by the pandemic.
Dr. Wiznitzer added that the study did not provide data on other aspects of the participants’ lives such as food security, economic resources, sleep habits, or diet. Additionally, it remains unclear which children were infected with the coronavirus during these years and how it might have influenced the brain.
Dr. Bradley Peterson, a child psychiatrist and brain researcher at Children’s Hospital Los Angeles, highlighted that MRI scans were conducted on different subsets of subjects before and after the pandemic. He suggested that the inability to track individual brain changes among the study participants might be due to this factor.
There is no “supporting evidence” to suggest that brain aging is solely a result of social isolation and not due to increased social media use, screen time, lack of physical exercise, or overall rise in stress related to COVID during the pandemic, Dr. Peterson added.
Kuhl acknowledged that future research is needed to deepen our understanding of the overall impact of the pandemic on the adolescent brain.
According to the University of Washington research team, prior studies have documented accelerated brain aging in teenagers who experienced pandemic lockdowns, but those studies did not examine gender differences.