Oxytocin
It has been shown that oxytocin differentially affects males and females. Females who are administered oxytocin are overall faster in responding to socially relevant stimuli than males who received oxytocin. Additionally, after the administration of oxytocin, females show increased amygdala activity in response to threatening scenes; however, males do not show increased amygdala activation. This phenomenon can be explained by looking at the role of gonadal hormones, specifically estrogen, which modulate the enhanced threat processing seen in females. Estrogen has been shown to stimulate the release of oxytocin from the hypothalamus and promote receptor binding in the amygdala.
C. Sue Carter
Carter studies social bonding, male and female parental behavior, the social control of stress reactivity and the social control of reproduction, often using animal models such as the socially monogamous prairie vole. Carter’s research focuses on neuropeptide and steroid hormones, including oxytocin, vasopressin, corticotropin-releasing hormone, and estrogen. Her research program has discovered important new developmental functions for oxytocin and vasopressin, and implicated these hormones in the regulation of long-lasting neural and effects of early social experiences. She also has a long-standing concern regarding the consequences of medical manipulations for human development and parent-child interactions, including the use of “pitocin” to induce labor and consequences of breast feeding for the mother and child. Most recently she has been examining the role of oxytocin and vasopressin in mental disorders such as autism, schizophrenia, anxiety and depression. Carter is also known for research on the physiological basis of social behavior, including studies that implicated oxytocin, vasopressin and hormones of the hypothalamic-pituitary-adrenal (“stress”) axis in the traits of monogamy including pair-bond formation. She pioneered the physiological study of socially monogamous mammals, including the prairie vole. In collaboration with Lowell Getz, Carter documented the occurrence of social monogamy in prairie voles. Her studies in rodents helped to lay the foundation for the studies of behavioral and developmental effects of oxytocin and vasopressin in humans which are in progress. In collaboration with Margaret Altemus she conducted some of the first studies documenting the importance of breast-feeding in the regulation of maternal physiology.