They discover in mice the mechanism that leads us to make new friends

A neural circuit activated by a hormone helps suppress interactions with familiar individuals to foster preference for new ones, according to a study conducted with mice and coordinated by scientists Spanish people.

These results could lead to the development of drugs to treat disorders such as separation anxiety or avoidant personality.

The research published by Cell is led by Félix Leroy from the Institute of Neurosciences (CSIC and the Miguel Hernández University of Alicante, both in Spain), and American scientists also participated in it.

Until now, it was not known whether the preference for new individuals came from neural circuits that foster motivation for novelty, or if, on the contrary, there were circuits that suppress interaction with already known individuals.

The motivation to interact with new individuals is a fundamental quality to live in society, as well as to interact properly.

The team discovered a group of neurons, located in the prefrontal cortex, which is characterized by producing corticotropin-releasing hormone (CRH) and emitting its axons to the region of the lateral septum.

This region of the brain is essential because it regulates what is known as motivated behaviors: the search for food, security, comfort, and socialization with their peers.

Through a combination of techniques, they found that when mice detect the familiarity of an individual, neurons in the prefrontal cortex are activated in response and release CRH in neurons of the lateral septum, which makes it possible to reduce interaction with individuals. acquaintances.

The pups prefer to stay close to their relatives, which is important because it guarantees survival and correct development, but this preference must change during the postnatal period to promote a preference for social novelty and thus acquire adult social behavior, Leroy points out.

The experiments carried out in this study show that the maturation of CRH expression in the prefrontal cortex during the first two weeks of life is what allows this change in social behavior to occur during development, explains the researcher. .

Up to 1% of the population may suffer from what is known as avoidant personality disorder, which clinically manifests as a form of extreme introversion.

Similarly, one of the most common anxiety disorders in children is separation anxiety, an unusually strong fear of being separated from familiar people, severely affecting their daily lives.

The researchers suggest that a deficiency of CRH in the prefrontal cortex or in its receptor in the region of the lateral septum could cause alterations in social interactions.

“Disturbances in social behavior are often associated with the onset of many psychiatric disorders, and we know that the regions implicated in our study are dysregulated in several psychiatric disorders.”, Leroy points out.

In addition, the results of this work open up new lines of research that could lead to the development of new drugs directed at the CRH system as a therapeutic target to treat social anxiety disorders and other types of psychiatric diseases that are associated with abnormal interactions, such as autism or the Depression.

Source: EFE