Boston | A study of adolescent brain development that tested children before and after the COVID-19 pandemic lockdowns in the United States found that girls’ brains aged far faster than expected, something the researchers attributed to social isolation.

The study from the University of Washington, published this week in the Proceedings of the National Academy of Sciences, measured cortical thinning, a process that starts in either late childhood or early adolescence, as the brain begins to prune redundant synapses and shrink its outer layer.