Pandemic has physically altered teenagers’ brains

Researchers from Stanford University initially recruited a representative sample of children and adolescents from the San Francisco Bay Area to participate in a long-term study on mental health during puberty.

The team compared MRI scans of 81 teenagers taken between November 2016 and November 2019 with those of 82 teenagers who were scanned between October 2020 and March 2022, after the Covid lockdowns were lifted.

The team found that normal physical changes to the brain which take place during adolescence – such as the thinning of the cortex, which is related to executive function, and the growth of the hippocampus and amygdala, which regulate memory and emotions – were significantly greater in the post-lockdown group.

Ian Gotlib, the study’s first author and Director of the Stanford Neurodevelopment, Affect, and Psychopathology (SNAP) Laboratory, expressed his surprise at the extent of the variation in each group’s brain structure.

“Brain age difference was about three years – we hadn’t expected that large an increase given that the lockdown was less than a year [long].”

Dr Gotlib also noted that, previously, such accelerated changes in brain age only appeared in children who had experienced chronic adversity, such as violence, neglect, or family dysfunction.

The results of the study, published in Biological Psychiatry: Global Open Science, aligned with existing data pertaining to worsening mental health among ‘Generation Covid’, with the post-lockdown group reporting more severe symptoms of anxiety and depression.

However, it is not year clear whether the changes in brain structure observed by the Stanford team are directly linked to deterioration in mental health.

Moreover, while similar brain changes are often accompanied by reduced cognitive function and memory problems in older adults, it remains to be seen whether accelerated brain aging is necessarily dangerous for teenagers.

Dr Gotlib and his team intend to track the study’s participants through later adolescence and young adulthood, to determine if the changes in developmental processes have permanent or negative consequences.

The researchers are also planning further investigations into the differences in brain structure of teenagers who have contracted the virus and those who have not.

The study’s findings could also have implications for other long-term studies that have spanned the pandemic, as scientists might have to account for abnormal brain development in future research on those who spent part of their adolescence on lockdown.

It is estimated that, in 2020 alone, an additional 53 million cases of major depressive disorder and 76 million cases of anxiety disorders arose due to the pandemic.

Related: Could Covid have changed people’s personalities?