in 2016, there was a group in Spain that first looked longitudinally at moms who were recruited before becoming pregnant and then scanned for a second time a few months after the birth of an infant. What they found is going to sound like a bad joke, but it’s actually we think a good thing, which is the brain got smaller. So it lost some gray matter volume between that first preconception time point and the postpartum scan.
It's official folks, having kids makes you an idiot :D
Always has been if you're rich.