Emotional contagion and resilience in the face of adversity

The negative emotional contagion experienced by bystanders who see what happens to their peers seems to generate resilience against a state similar to depression. At least in mice, which have been the subjects of a recent study on this question.

In experiments, bystander mice that briefly observed other mice being harmed later showed fewer signs of behavioral helplessness when confronted with their own harmful event, compared with mice that did not observe peers being harmed.

The study was carried out by a team led by Sarah Mondoloni of the University of Lausanne in Switzerland.

Mondoloni and his colleagues have shown that resilience in these mice requires an increase in serotonin release in a part of the brain called the lateral habenula.

“These findings support the idea that, as in humans, moderate trauma can promote resilience, allowing individuals to cope with future challenges,” the study authors explain.

They also note that their findings could refine the current model of key neural circuits involved in depression.

Negative emotional contagion in bystander mice occurred when they watched their cage mates receive a mild electric shock to their paws, before experiencing the shock themselves.

Serotonin, released in a part of the brain called the lateral habenula, is the key substance mediating resilience. The image shows neurons inside a mouse habenula. (Image: Laboratory of Manuel Mameli, UNIL)

Researchers suggest that serotonin release helps build resilience in bystander mice by reducing neuronal bursts in the lateral habenula.

This type of neuronal hyperactivity is the basis of depressive behaviors in mice.

The study is titled “Serotonin release in habenula during emotional contagion promotes resilience.” It was published in the academic journal Science. (Source: AAAS)