The stress of living through pandemic lockdowns has accelerated aging in the brains of teenagers. The effects are similar to those previously observed as a result of violence, neglect, and family dysfunction.

Even if you've left adolescence far behind, you might remember that it can be a tumultuous time in terms of thoughts and feelings, and there's a lot of reorganizing that goes on in the brain – even without a global pandemic and the associated lockdowns.

A recent study by researchers from Stanford University and the University of California, San Francisco, concluded the pandemic had 'sped up' some of this reorganizing, thinning of the cortex and increasing the size of the hippocampus and the amygdala sections of the brain.

"We already know from global research that the pandemic has adversely affected mental health in youth, but we didn't know what, if anything, it was doing physically to their brains," says psychologist Ian Gotlib, Director of the Stanford Neurodevelopment, Affect, and Psychopathology (SNAP) Laboratory in California.

The team looked at magnetic resonance imaging ( MRI) brain scans of 81 children taken before the pandemic (between November 2016 and November 2019), and 82 children taken during the pandemic (between October 2020 and March 2022) but after lockdown restrictions had eased (spring 2020, in California).

Next, the researchers matched children from both groups using factors including sex, age, pubertal status, ethnicity, early life stress, and socioeconomic background, to give them multiple comparison points.

What the scans showed was that the brain aging process had seemingly accelerated in the post-pandemic group. Lockdown periods of less than a year had resulted in the equivalent of three years of brain aging in the second selection of youngsters.

Poorer mental health was also noticed in the post-pandemic group, though it's not clear if that's directly related to brain age. What this study can't tell us is whether these changes are going to be permanent, or whether there are further mental health problems that will arise from the accelerated changes in these key brain structures.

"Will their chronological age eventually catch up to their 'brain age'?" asks Gotlib. "If their brain remains permanently older than their chronological age, it's unclear what the outcomes will be in the future.

"For a 70 or 80-year-old, you'd expect some cognitive and memory problems based on changes in the brain, but what does it mean for a 16-year-old if their brains are aging prematurely?"

More research is going to be required to find out. The team plans to continue tracking the same group of people as they get older, looking out for further changes in brain structure and any mental health complications that might develop.

All of the young people had been recruited for a study on depression during puberty. However, the arrival of COVID-19 – and a necessary pause in the study during lockdowns – sent the research in a different direction.

The findings could indicate a need to correct other brain studies that will have to take this neurological aging acceleration into account. Kids that have lived through the pandemic aren't necessarily going to be in the same neurological state as the kids that came before them, though picking out those differences won't be straightforward.

"The pandemic is a global phenomenon – there's no one who hasn't experienced it," says Gotlib. "There's no real control group."

The research has been published in Biological Psychiatry: Global Open Science.