I have always thought that the so called "Maternal instinct" was something that few mothers could develop. Maybe is something that every female have, even in the animal kingdom.
The Rockefeller University's researchers in New York have tested the maternal behaviour in mice. They divided a large number of mice in half; the first group got lowered the chemical located in an especific region of the brain, medial preptic area, responsible for the protective care, sexual behavior and aggression, where there are high levels of oestrogen. The second group was being observed with the normal levels of the chemical in the especific group of neurons.
The engineered group, changed the "maternal" behaviour automatically, this is, the licking, nursing and protection from the female mice to their pups were almost zero. The results were especific to the maternal/sexual behavior gene since no other behaviour, such as sexual receptivity or aggression, changed during the experiment.The other group remain intanct, as evidence that the "maternal behavior" is directly related to the gene that is responsible for protecting, caring and nursing their pups.
This experiment can aboslutely show us that the maternal care and nursing in mice can be applied to other species, even in humans since it gives the opportunity to experiment with humans, and provide the prescriptions of chemicals to enchance the maternal care.
What happens in those cases where mothers do not care about ther children? Is it possible to generalize this evidence to the human behavior?
