The Mommy Brain

A: I really believe it starts with looking at the world and themselves differently. In one study, researchers found that pregnant women overwhelmingly felt they were weaker in mental strengths, such as focus and memory, whereas tests showed they weren't. The researchers speculated that this might be because of what they had internalized about others' expectations. One legacy of feminism has been this uncomfortableness about women rearing children and getting close to children. We've come to see our children taking things away from us, and we've lost the sense of how much they're adding to us, as people, as thinkers.

Q: Are fathers, adoptive parents and other caregivers shut out of the intellectual benefits of motherhood?

A: Absolutely not. Recent research has tracked important hormone fluctuations in fathers that appear to be stronger the more involved the dad is with the babies. There may even be hormonal changes in adoptive parents, though the evidence of that is much sketchier. But certainly the experience of being a dedicated caregiver to a child, wrestling with that child's problems and teaching him or her about the world, is tremendously valuable.