A PILOT STUDY OF OXYTOCIN REACTIVITY AND FUNCTIONAL MRI

点击翻译按钮获取中文摘要

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The mother-infant relationship has been characterized as one of the most important relationships affecting the health and development of the human species. When that relationship involves child abuse or neglect, it is associated with a diverse range of adverse neurodevelopmental outcomes in the offspring, including cognitive and academic delays, psychiatric illness, social impairment and delinquency. However, in order to understand the neurobiology underlying child abuse and neglect, it is important to define the nature of normal mother-infant relationships. Recent fMRI studies have demonstrated distinctive patterns of neuronal activation, measuring maternal response to infant cries. Activated brain areas include the right medial prefrontal and orbitofrontal cortices, medial thalamus, cingulate cortex and other areas shown in animal models to be associated with maternal behavior. Similar patterns of activation have also been seen on viewing faces of infants and romantic partners, and with induced feelings of sadness relating to intimate relationships. These findings suggest that there may be a common neural substrate relating to social attachment and affiliation. Facial recognition and processing is thought to have a vital role in social communication, being imprinted during a critical phase of neural development in early infancy. This study aims to more clearly define the brain areas activated by a mother's emotional response to viewing her infant's face. Animal research has also established that the central oxytocinergic system facilitates the onset and maintenance of maternal behavior in rats. Oxytocin receptors in animals have been identified in several brain regions and nuclei consistent with human fMRI studies of maternal behavior. However, it is still unclear whether peripheral oxytocin concentrations are reflective of central activity, with animal models suggesting otherwise. A recent paper by Light et al., demonstrated that a peripheral oxytocin response to stress was most prominent after mother-infant interaction. It is hypothesized that - at least in a subgroup of mothers - oxytocin production will be stimulated by mother-infant interaction, and that these changes will correlate with fMRI activity levels. In addition, this pilot study of healthy, stable mothers may lead to further study of neglecting mothers, in order to better understand the pathophysiology underlying neglect. As the most common form of child maltreatment, with over 540,000 substantiated cases each year in the United States, further research is needed.