Dendritic growth in medial prefrontal cortex and cognitive flexibility are enhanced during the postpartum period.

The postpartum period is associated with numerous hormonal changes, some of which have been linked to detrimental effects on the medial prefrontal cortex (mPFC), a brain region involved in cognition. Here, we investigated whether mPFC structure and function are negatively influenced during the postpartum period, an outcome that might be predicted by the maternal hormonal milieu. Mother rats were tested on an attentional set-shifting task, and dendritic architecture of layer 2/3 mPFC pyramidal neurons was analyzed. Mother rats exhibited increased dendritic spine number in the mPFC, an effect that coincided with improved attention and behavioral flexibility. These findings suggest that the postpartum period is associated with promotion of neuronal growth in the mPFC and enhanced cognitive function.