Researchers at the RIKEN Research Center in Japan have identified a special category of neurons that make mothers protect their children.
In a new study, Kumi Kuroda and her colleagues at the RIKEN Research Center have discovered a function in the brain region that is responsible for maternal defense mechanisms: it forces mothers to take risks and protect their babies in any situation.
This can be traced to the example of chickens or cats: they attack all people and animals approaching their nest or den.
Humans and animals can suppress some instinctive behavior and act differently if they need to take care of their offspring. We found that an increase in the activity of this group of neurons in the hypothalamus of mice makes them take more active care of their offspring and at the same time suppresses their instinctive desire to avoid dangerous situations.
Kumi Kuroda, employee of the RIKEN Research Center (Japan), one of the authors of the study
A small set of neurons located inside the preoptic region of the hypothalamus is responsible for the work of the open area of the brain. This is one of the deepest regions of the brain, which, presumably, controls the sexual behavior of animals and humans, as well as their response to thirst, temperature fluctuations and some other simple stimuli.
While observing the activity of different types of neurons in the preoptic region in the brains of newly born female mice, the authors discovered a small group of nerve cells: it actively responded to molecules of calcitonin, a hormone that controls the balance of calcium and phosphorus in the body. Further, the authors tracked how the behavior of mice would change if the work of these cells was blocked.
It turned out that this procedure made the rodents lose interest in protecting their offspring. This was manifested in the fact that such mice did not transfer their offspring to the nest, did not cover it with their bodies and abandoned the mice at the first signs of danger.