Neuroendocrine Basis of Impaired Mothering in Rodents

Abstract

The maternal bond is the most important pro-social bond in female mammals, and its quality can affect the well-being of both infant and mother. Her caregiving behavior is extremely important to ensure not only the survival of the young but also their proper development. To enable the onset and maintenance of maternal behavior, hormonal levels (such as estrogens, progesterone, and lactogens) change during pregnancy and lactation, thereby also leading to alterations in neuropeptide systems. On the one hand, “pro-maternal” neuropeptide systems, like oxytocin (OXT), vasopressin (AVP), and prolactin (PRL), need to increase, whereas on the other hand, the activity of the “anti-maternal” corticotropin-releasing factor (CRF) system needs to be downregulated. If such brain adaptations are perturbed, maternal behavior can be impaired, potentially resulting in infant neglect. In this chapter, we discuss how altered neuroendocrine transmission can promote poor mothering, focusing mainly on rodent models. We suggest that increased CRF and decreased OXT, AVP and PRL transmission impairs maternal behavior, with similar, yet different, brain regions at play. For instance, the medial preoptic area is a notable region in the maternal brain circuitry, where neuroendocrine impairments can lead to maternal neglect. Since episodes of maternal neglect and bond disruption are becoming more prevalent, we believe it is crucial to better elucidate their neurobiological basis to develop potential intervention strategies.