The Plasticity of the Human Maternal Brain

Kim, P., Leckman, J. F., Mayes, L. C., Feldman, R., Wang, X., & Swain, J. E. (2010). The plasticity of human maternal brain: longitudinal changes in brain anatomy during the early postpartum period. Behavioral Neuroscience 124(5), 695-700.

Chapter 7 in the text emphasizes the plasticity of the developing human brain from the embryo stages prenatally all the way into young adulthood. For instance, there are certain critical periods of special plasticity during which certain tasks or developmental milestones are reached (such as motor skills and language). Even further, researchers have even pinpointed times during the early stages of life that are “better” and “worse” times for brain injury to occur. With all the focus on the younger human brain, it can be easy to overlook the fact that neural connections are still being primed well into older adulthood. Our brain remains a level of plasticity throughout life, and the research article I found provided interesting contrast to the emphasis in the text. The researchers in this article also emphasized the adaptability of the human brain during and after pregnancy, but differently focused on the brain of the mother, not the child. Drawing from previous research on animals, researchers looked for similar structural changes in nineteen human mothers’ brains that correlated with maternal behaviors. They examined the participants’ brains via MRIs at 2-4 weeks and 3-4 months after giving birth to their child. Researchers found similar results in humans that had been found in animals: there were increases in gray matter volume in the prefrontal cortex, parietal lobes, hypothalamus, substantia nigra, and amygdala. The researchers’ hypothesis that changes in behavior to perform maternal behaviors coincided with changes in certain regions of the brain was correct. Even more interesting, mothers who positively perceived their baby were more likely to have gray matter volume changes in the hypothalamus, amygdala, and substantia nigra. An implication of this study that was presented from the authors was that the postpartum time for a mother is a sensitive time (perhaps a “critical period,” in my own words) for the development of sensitive mothering and changes in these brain areas may be important to promote sensitive maternal behaviors.