The role of prefrontal somatostatin interneurons in emotional contagion

The role of prefrontal somatostatin interneurons in emotion recognition is well characterized. Here, for the first time, we investigated the role of these neurons during remote transfer of emotional information in the safe environment of the home cage. To do that mice with fluorescently labelled somatostatin interneurons were housed in pairs for three weeks, one labelled an Observer, and the other a Demonstrator. In the test session, the Demonstrator was subjected to aversive stimuli outside of the home cage, while the Observer remained there undisturbed. Upon the return of the Demonstrator to the home cage, we recorded the interactions of the two animals. The behavior of both partners, assessed and classified with machine learning algorithms, was clearly affected by the emotional state of the Demonstrator. To assess the role of prefrontal somatostatin interneurons in this process we chemogenetically manipulated their activity in the Observers and found that activation of these cells abolishes the enhanced social investigation of a stressed Demonstrator. This is associated with disinhibition of the prefrontal cortex. The manipulation also affects the neuronal activation patterns in Demonstrators, which seems to reflect the change in the behavior of the Observers.