R. Sullivan, M. Openak and D. Wilson.
The quality of parental care has enduring effects on brain circuits, including ubiquitous changes in gene expression, myriad neurotransmitters/hormone, molecular signaling and anatomy. Less is known about the immediate impact of parental care quality on neural processing or mechanisms that support maternal behavior’s translation into neural signals to alter development. Here we present data indicating that the attachment figure has a unique ability to assess and regulate the infant’s brain. We provide three examples of pup’s unique processing of sensory stimuli with the caregiver vs. alone and further illustrate that the quality of the pup’s attachment to the caregiver impacts this process. These maternal modulated brain signals have profound effects on pup’s immediate behavior and influence the developmental trajectory. First, mother’s social buffering of pup’s stress response alters the offspring’s neural and behavioral response to trauma. Second, extended experience of trauma experienced from or with the caregiver derails the caregiver’s ability to blunt amygdala responsiveness via dopamine. Third, maternal control over the pup’s brain occurs minute to minute within the nest during typical care and maltreatment: we show that the mother’s presence modifies pup’s cortical synchronization, although maternal behaviors (milk ejection, grooming) increases desynchronization, due to the pups noradrenergic system. This system is disrupted during maltreatment, and this disruption continues into adulthood if the maltreatment experience is prolonged. Understanding how the mother controls the pup’s neural processing of sensory stimuli, and its further manipulation by the quality of attachment, will highlight mechanisms by which maternal care changes infant behavior and alters the developmental trajectories.