Study Finds Tears Lower Aggression, Shedding Light On Why We Cry

A new study by researchers at the Weizmann Institute of Science shows that human tears contain chemicals that reduce aggression in others. 

The research, according to the Weizmann Institute, provides an answer to the unsolved question of why people cry. 

The study, which has been published in US journal PLOS Biology, found that when men smelled tears produced by women, there was a reduction in their brain activity related to belligerence and their behavior became less aggressive. 

The researchers monitored the brains of men as they played a two-person game designed to trigger aggressive behavior and were led to believe that their opponent was cheating.  

Men who were exposed to the tears of women during the game saw their aggressive behavior fall by around 44 percent, the study found.   

The tears of blind mole rats and mice have a similar calming effect, with the former even smearing themselves in tears to lower aggression shown by dominant males.  

“We’ve shown that tears activate olfactory receptors and that they alter aggression-related brain circuits, significantly reducing aggressive behavior,” said Prof. Noam Sobel of Weizmann’s Brain Sciences Department, where the research was conducted. 

“These findings suggest that tears are a chemical blanket offering protection against aggression – and that this effect is common to rodents and humans, and perhaps to other mammals as well,” he said.