Less is More

(Image from albuquerque.citymomsblog.com) 

Science shows that pregnancy shrinks women's brains permanently (pause for joke insertion....ok, resume):

Comparing the scans showed significant reductions in the volume of grey matter in the brains of the new mothers....And it was persistent, too. When the researchers retested the mothers two years later, most of the alterations were still present.

However, it's possible that the loss of brain cells not only didn't cause harm ("administering a few simple cognitive tests to the new mothers—including tests of memory—revealed no obvious changes in performance") but could be beneficial [bold added]

The ones with the greatest reductions in grey-matter volume were, on the whole, the most strongly bonded....it is probably evidence of a process called synaptic pruning, in which little-used connections between neurons are allowed to wither away, while the most-used become stronger. That is thought to make neural circuitry more efficient, not less so.

Anecdotal evidence, to be sure, but most mothers we've encountered are better at multitasking and organization than their male partners.

The scientists may attribute it to synaptic pruning, but your humble blogger calls it determination and focus borne out of necessity. The former is science, the latter is character, which will never be measured in a lab.