With her second child growing larger by the day, Liz is experiencing the tyranny of her pregnancy. Her belly seems impossibly huge to her. Easy sleep is a distant memory now that she must contend with tens of pounds of extra girth. With fiery heartburn following every meal, she feels as if she is subsisting on a diet of small volcanoes.
But Liz is not just any late-term mother-to-be. She is also a neuroscientist studying the changes that occur in a mother's brain—in fact, she co-authored this article. Although it will not relieve her indigestion, she derives some comfort from a new and growing body of research that is revealing the marked and generally positive alterations that accrue to a mother's brain.
Because the maternal brain emerges gradually, the construction site it becomes in the interim can cause some problems for its owner. Some mothers complain of fuzzy-headedness, and certain data even show minor brain shrinkage during pregnancy. But the compensations are great. Research suggests that motherhood enhances certain types of cognition, improves resistance to stress and sharpens some kinds of memory. On the face of it, the fact that the nervous system manages to transform a new mother from a self-centered organism into an other-focused caregiver is actually quite impressive. All it takes is for new neurons to sprout, certain brain structures to blossom in size and waves of powerful hormones to batter the pregnant woman's physiology. The result is a different and in some ways better brain—or at least one capable of juggling the challenges of everyday life while maintaining a laserlike focus on the baby.