A new review paper presents accumulated evidence that the brains of both mothers and fathers change in the service of parenting behavior. In addition, structural, electrophysiological and molecular changes occur in maternal and paternal brain regions not traditionally associated with parenting. Some of these brain areas are more widely known to be involved in cognition and mood regulation.

Maternal and paternal influences on neuroplasticity in the hippocampus and prefrontal cortex are highlighted in the review paper “Parenting and plasticity” published October 2010 in Trends in Neuroscience. The hippocampus and prefrontal cortex are well known and extensively studied for their roles in learning, memory, mood regulation, and cognition.

Some of the other brain regions known to be involved in maternal and paternal behavior include the olfactory bulb, medial preoptic area, lateral septum, bed nucleus of the stria terminalis, and the amygdala.

As a non-parent did you ever get annoyed by a crying baby? If you became a parent did you notice how your reaction to crying babies changed? Your brain changed! Data show that exposure to crying infants activates the amygdala and prefrontal cortex in fathers and mothers, but not in non-parents.

It’s been known for some time that mothers exhibit drastic alterations in hormones including decreased estrogen and increased oxytocin and prolactin. However, it has only recently been appreciated that fathers have similar, but not identical, alterations in these hormones including increased estrogen, oxytocin, prolactin and glucocorticoids. Oxytocin levels in human fathers are positively related to the amount of affection the father displays toward his infant. Paternal behavior is also related to reduced levels of testosterone.

These were just a couple of examples of how the brains of parents are clearly different from those of non-parents. The changes in maternal and, especially, paternal brains induced by the presence of offspring have only begun to be looked at. I encourage those interested in the subject to read this brief review paper.