The findings were published in the Proceedings of the National Academy of Sciences. Earlier research identified the medial preoptic area of the brain as the area controlling aggression, sexual receptiveness and maternal care in mice. The chemical mechanisms influencing these behaviors has remained unclear. Previous studies have concluded that nerve cells react to estrogen, the female sex hormone, and contain high levels of a chemical linked to maternal care and sexual behavior.
In the Rockefeller University study led by Dr. Ribeiro, the scientists diminished the levels of the chemical in the medial preoptic area of the female mice, to isolate the results. They discovered that mice spent less time caring for their offspring, but their aggression levels were unaffected.
The group was inspired to undertake this study because “We knew mice lacking this gene (ER alpha knockout animals) were poor mothers - they have a lot of infanticidal behavior,” says Dr. Ribeiro. “The novelty of this study is that it shows that silencing of this gene in one specific area of the brain, equivalent to 1cm3 in the human brain, abolishes many aspects of maternal behavior - bonding, licking and nursing. These studies supported this hypothesis.”
Dr. Ribeiro says, “Mice and women express different versions of these receptors, and it is hypothesized that different versions are associated with different maternal capacities - in mice, this is certainly the case. Furthermore, there is evidence from mice that there are modifications that occur in young pups that determine what type of mother a female pup will become.”
“Our studies show that the type of receptor, or the total lack of this receptor, in this particular area of the brain affects the ability to be a ‘good’ mother,” she adds.
About the College of Mount Saint Vincent
The College of Mount Saint Vincent is an academically excellent, authentically inclusive, Catholic and ecumenical liberal arts college. It combines a strong core curriculum with a full array of majors in the liberal arts and selected professional fields of study, including accounting, business administration, education, and nursing. Through its School of Professional and Continuing Studies, the College extends its primary undergraduate mission by offering high quality graduate studies in business, education and nursing and an array of undergraduate and certificate programs serving non-traditional students. Mount Saint Vincent is located on a pastoral campus in New York City, with easy access to all the educational, cultural, and recreational opportunities that the City affords.
Director for College Relations