Coming of age was particularly tumultuous for teenagers during the pandemic. School closures and social distancing may have kept them safe, but it also made them lonely. That impacted their brain growth, particularly for teenage girls, who tend to be more social than boys. In fact, the brains of teen girls rapidly aged during the pandemic, outpacing boys’ cognitive development, according to a new study from the University of Washington.
Kalina Michalska, psychology professor and director of UC Riverside’s Kids Interaction and NeuroDevelopment Lab, explains that the study’s authors identified what brain maturation looked like before and after the pandemic, to see how results differed from expectations. On average, girls’ brains aged by more than four years than what was expected in comparison to approximately a year and a half for boys.
“What they found is faster-than-expected cortical thinning, and importantly, females showed more widespread and faster and more significant thinning in … the cortex, and the thickness of the cortex, which suggests a greater developmental impact on female brains,” she says. “And so it suggests that these kinds of lifestyle changes associated with COVID-19 resulted in a deviation or difference from the normative pattern of thinning during adolescence in particular, and those effects were more dramatic in females than males.”
Michalska explains that thinning in this brain region is beneficial — and part of normal neurological development — allowing us to have language function, consciousness, emotions, and movement.
Typically, however, thinning happens over long periods: “The reason why the cortex thins throughout late adolescence, early adulthood, even middle adulthood and on — is to give us that time to develop adequately. To give us that time to take in the environmental input, respond to the environmental input, while we still depend on our caregivers. So the fact that it's accelerated, the fact that it's thinner, means that now we're less reliant on other people.”
However, this comes with increased risks of psychiatric disorders, anxiety, depression, and behavioral disorders, she points out.
The quicker cortical thinning happens, Michalska says we don't have enough time to learn from the environment. “We do see that there's associated risks for mental health disorders. … On the other hand … under stress, maybe it's more adaptive to be responsive to the environment faster.”
In Michalska’s own research lab, her team focuses on the mental health of Latina girls and their caregivers. During the pandemic, she found that girls had higher depression symptoms and worries about their families.
However, when caregivers made meaning of the shutdowns, and the benefits it provided, such as more family time, pro-social behaviors increased, Michalska points out.
“So absolutely, it took a mental health toll, but there were also some silver linings, and we also saw increases in helping … empathy, sympathy, and the like.”
She notes that while cortical thinning occurs, the brain continues to be plastic and compensates, i.e., it can learn to regulate emotions.
Michalska emphasizes that COVID-era struggles with mental health and/or academics didn’t stem from teens personally doing something wrong. Instead, those were social stressors, and remembering this could help girls and boys be kinder to themselves. It may also shift conversations and what educators and clinicians demand of young people.