Mother-child bond largely controlled by hormones?
Caring for the mother is vital for newborns. But the mother-child bond is impaired in some women, such as in the case of the so-called postpartum depression. Here the interaction of the hormones oxytocin and testosterone could possibly have a decisive influence.
Sarah Holtfrerich and Jun.-Prof. Have investigated the influence of hormones on the mother-child bond. Dr. Esther Diekhof from the Department of Neuroendocrinology at the Institute of Zoology at the University of Hamburg in a recent study. "Different hormones influence maternal feelings" and "while oxytocin strengthens the bond with the child, testosterone seems to suppress maternal behavior," the university said on the study results. These were published in the scientific reports.
Babies activate key stimuli in the reward system
Various biological factors influence the reactions of adults to babies and toddlers. Here, for example, the special childish facial features with big eyes, snub nose and chubby cheeks are to be mentioned. These typical facial features, also known as children's patterns, act as a key stimulus in the brain's reward system and cause parents to look after their offspring, the scientists explain. However, according to the latest study results, hormones also have a significant influence on the bond between mother and child.
Brain responses analyzed
In their study on 57 test subjects, the Hamburg researchers examined how the two hormones oxytocin and testosterone interact and whether they influence the reactions to the child's pattern. The participants were divided into two groups, the first group receiving oxytocin and the second group a placebo. Furthermore, the testosterone level was measured in the test subjects. The researchers then showed the women pictures of adults and children with different child patterns. Functional magnetic resonance imaging (fMRI) was used to record the brain activity of the study participants.
Increased activity in the reward system
"When we administered oxytocin to women with high testosterone levels, activity in the brain's reward system increased as soon as they saw baby faces," reports Sarah Holtfrerich of the study results. After the administration of oxytocin, the women also reacted more sensitively to the child's pattern. According to the researchers, the administered oxytocin had no effect on women with low testosterone values.
Negative effects of testosterone are balanced
According to the latest study results, oxytocin can apparently compensate for the negative effects of testosterone on the mother-child bond and motivate the caring behavior of women. The sex hormones oxytocin and testosterone influence the reward system in the brain, whereby oxytocin, which is often referred to as cuddly hormone, strengthens the social bond between mother and child, while testosterone presumably has a negative effect on maternal behavior, the researchers emphasize.
Potential for pharmacological research
Since the administered oxytocin had no effect in women with low testosterone values, the study authors assume that low values of the male sex hormone in women sufficiently promote maternal behavior and that additional influence of oxytocin is not necessary for them. In further studies, the researchers are now planning to check the results on mothers and fathers. There is also potential for basic pharmacological research, "since an oxytocin deficiency is most likely to play an important role in psychiatric disorders such as postpartum depression," the University of Hamburg said. (fp)