The psychobiology of parenting in mammals

The neurobiology of mammalian parenting and the biosocial context of human caregiving

This article is part of a Special Issue "Parental Care". Research on the neurobiology of attachment, pioneered by scholars in the generation that followed the discovery of social bonding, examined the biological basis of mammalian parenting through systematic experiments in animal models and their application to theories on human attachment. This paper argues for the need to construct a theory on the neurobiology of human attachment that integrates findings in animal models with human neuroscience research to formulate concepts based on experimental, not only extrapolative data. Rosenblatt's (2003) three characteristics of mammalian parenting - rapid formation of attachment, behavioral synchrony, and mother-offspring attachment as basis of social organization - are used to guide discussion on mammalian-general versus human-specific attributes of parental care. These highlight specific components of attachment in rodents, primates, and humans that chart the evolution from promiscuous, nest-bound, olfactory-based bonds to exclusive, multi-sensory, and representation-based attachments. Following, three continua are outlined in parental behavior, hormones, and brain, each detailing the evolution from rodents to humans. Parental behavior is defined as a process of trophallaxis - the reciprocal multisensory exchange that supports approach orientation and enables collaboration in social species - and includes human-specific features that enable behavioral synchrony independent of tactile contact. The oxytocin system incorporates conserved and human-specific components and is marked by pulsatile activity and dendritic release that reorganize neural networks on the basis of species-specific attachment experiences. Finally, the subcortical limbic circuit underpinning mammalian mothering extends in humans to include multiple cortical networks implicated in empathy, mentalizing, and emotion regulation that enable flexible, goal-directed caregiving. I conclude by presenting a philosophical continuum from Hobbes to Lorenz, which illustrates how research on the neurobiology of attachment can put in the forefront the social-collaborative elements in human nature and afford a new perspective on the mind-brain polarity.

Antipsychotic-induced somnolence in mothers with schizophrenia

Although it is known that many antipsychotic drugs, at the doses prescribed for schizophrenia, are sedative and cause daytime drowsiness, the effect of potentially diminished vigilance on parenting parameters has not been studied. The aim of this paper is to advise clinicians about sedative load in mothers who are prescribed antipsychotic medication. A Medline search was conducted into the sedative effects of antipsychotics, with the following search terms: sleep; sedation; somnolence; wakefulness; antipsychotics; schizophrenia, parenting, maternal behavior, and custody. The results showed that antipsychotic drugs differ in their propensity to induce sedation and do so via their effects on a variety of neurotransmitter systems. It is important to note that mothers with schizophrenia risk losing custody of their infants if they are perceived as potentially neglectful because of excessive daytime sleepiness. Clinicians must choose antipsychotic medications carefully and monitor for sedative effects whenever the patient has important responsibilities that require the maintenance of vigilance.

Immobility in the swim test and observations of maternal behavior in lactating flinders sensitive line rats

In order to elucidate the relationship between maternal behavior and depression, the Flinders sensitive line (FSL) model of depression was studied and compared to Sprague-Dawley (SD) controls. Immobility in the swim test was measured, as an index for depressive-like behavior, and frequencies of maternal and non-maternal behaviors were recorded using short un-intrusive observations in the home cage. Lactating FSL rats displayed higher levels of immobility in the swim test compared to controls, indicating depressive-like behavior. In addition, compared to SD rats, FSL dams showed less frequent pup licking and non-nutritive contact with pups during the first and third weeks of lactation. In the third postpartum week, FSL dams showed less frequent nursing postures and more frequent self-directed behaviors. Thus, lactating FSL dams exhibit both depressed-like behavior and some abnormalities in maternal behavior.