Women became smarter after becoming a mom, for men you just become more adventurous…

Well, from this research on mice/rats and if you believe that we are similar in some sense, it seems that:

For women:

Lambert's research on mother rats has provided mounting evidence that motherhood benefits the brain. She found that mom rats do better on learning and memory tests than non-moms, and are also bolder, suggesting that they are protected against the damaging effects of stress.

For men:

Lambert's team first compared dads with bachelors– males who had never been dads– in the Mister-Mom species, with results similar to her findings in rats. "We did find that the dads were better foragers and they explored a novel stimulus more than the non-dads did," says Lambert.

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