The title of the article is more on the sensationalist side unfortunately, the actual paper gives a different view [1].

There are two parts worth quoting:

> Although cortical reductions sometimes reflect a process of neurodegeneration, they can also be a sign of refinement and specialization of neural circuits. Adolescence, for instance, is a life period characterized by the continued elimination of redundant synapses (i.e. synaptic pruning) which parallels cognitive and emotional development (Selemon 2013). In the context of the transition to parent-hood, several examples across human and non-human mammals show functional improvements after reductions in brain markers (Pawluski et al. 2022).

And:

> Although we found converging evidence of cortical reductions across the two samples, a number of divergent findings also emerged. First, when disentangling the cortical volume reduction, Californian fathers displayed significant reductions in area and Spanish fathers in thickness. Changes in the area may reflect changes in the number of cells located between radial columns of the brain, while changes in thickness may reflect changes in the number of cells within ontogenic columns (Petanjek et al. 2011). Secondly, the volume of the dorsal attentional network, which supports goal-directed attention, was significantly reduced in Spanish fathers, while it did not show significant changes in Californian fathers. Combined with the default mode network, this network may control sustained attention (Spreng et al. 2010, 2013), a behavior that is often required during childrearing. It is possible that these inconsistent results at the statistical level may be due to the different scan timing windows or to cultural or behavioral differences. For example, due to more generous paternity leave policies in Spain

1: https://academic.oup.com/cercor/article/33/7/4156/6691667

Thank you!