Speak to any new mother, and they’ll tell you what science has shown to be true for quite some time now: pregnancy not only involves a lot of changes to the body, but also significantly affects the brain. The term used to describe this effect? “Baby Brain” - a feeling of forgetfulness and lack of focus that new mothers often experience. Despite this being a common phenomenon, we know surprisingly little about the consequences of pregnancy on the brain. So we did some digging to learn more.
Here's what we found: in a 2016 article published in nature neuroscience, researchers examined the brains of women before and after pregnancy. They found that, when compared to women who had never been pregnant, post-pregnancy women had a reduction in the brain’s gray matter, including in the hippocampus and surrounding areas – areas that support memory. Interestingly, areas related to social cognition (how people process social interactions) and theory of mind (being able to observe and understand another person’s perspective) showed the greatest reductions.
When the same women were scanned two years later, gray matter within memory regions had increased, but the brain areas responsible for theory of mind had not. The reduction of gray matter in these areas is thought to reflect the brain fine-tuning these areas post-pregnancy. What does this all mean? Essentially, this refinement of brain networks post-birth allows mothers to tune in to aspects of social cognition that are important for motherhood - things like increased emotion and face recognition, making the transition into motherhood easier.