Research from Yale University shows that within months of childbirth the mom's brain grows. The growth is said to be related to hormone changes the female body experiences after birth. The areas of the brain affected are those associated with behavior and motivation.
Mothers that were excited and overwhelmed about their new baby had more growth than those that were more reserved. A mother's craving to look after her baby, according to the Yale study, is driven more by active brain building than instinct.
Neuroscientist Pilyoung Kim compared the MRI brain images of 19 women. The first images were taken two to three weeks after birth, then followed with another set of images three to four months after. The women were about 33 years old and all breast feeding. There were no signs of postpartum depression and about half had other children.
Brain scans showed a small yet significant increase in gray matter volume in different parts of the brain; areas affected were associated with maternal motivation, reward and emotion processing, and reasoning and judgment.
Because of hormonal changes that occur immediately after birth, this makes a new mother's brain more susceptible to growth in response to her infant, according to the researchers.