It’s not as creepy as it sounds. We promise.
According to researchers, it is merely based on human biology and hormones.
New research has discovered that tears themselves appear to take on a role as a chemical peacemaker between men and women.
But how might one ask?
Well, let’s real it back to other animals who react similarly to tears.
Other Animals and Their Reactions
Just to be clear, we, as human beings, are animals as well.
No need to be anthropocentric.
Particularly, in reacting to human tears, we are similar to other fellow mammals.
There has been an array of behavior in animals regarding tears, that has been uncovered.
For example, dogs have been found to shed tears when reunited with their owners after a long period of separation.
Meanwhile, the tears of baby mice contain molecular cues that cause for their lactating mothers to reject male advances.
Alongside, mole rat subordinates cover themselves in their own tears to deflect aggression from dominant rats in their environment.
Finally, one of the behaviors is that chemically female rats also lower aggression in their male counterparts.
This is shown in the sense that the pheromones in female mice’s tears cause for males to stop fighting amongst each other and pursue to mate with the female instead.
But the question of when did this question arise for human beings instead?
Beginning Human Research
To begin this long journey, a study published in 2011 by Sobel and colleagues showed that the tears of female human beings decreased sexual arousal in their male counterparts.
This was due to reduced levels of testosterone.
Though this study scratched the surface of research to this unique subject, it raised even furthermore curiosity.
It also proved to be difficult to get more answers to this subject, as it was very difficult to collect tears from donors.
According to researchers, they needed at least one milliliter of tears to use on each experimental participant.
Meanwhile, when attempting to create a new study on this subject, only six out of 100 women were able to provide the right amount of tears to experiment with.
Though the women were provided with a variety of stimuli to make them cry, scientists eventually shifted to using saline solution trickled down women’s faces as a control substance.
Details of the Newfound Study
Though the new study came with a variety of obstacles along the way, the researchers were able to conduct it.
The researchers found 25 male volunteers, to play a game that tests out aggression in human beings.
They also had a second group of 26 males participate, of which were having functional magnetic resonance imaging (fMRI) processing done on them while playing.
The premise of the game is that participants believe that they are competing against other individuals.
However, in reality, it is truly a computer algorithm that they are up against.
Within the game, the computer algorithm steals money from the participants, which innately irritates participants.
However, participants are left with the option to either take revenge and not receive any monetary gain, or to let their opponent get away with it and continue receiving more money themselves.
Prior to having participants play the game, they had them inhale from a “sniff jar” that contained “assorted odors”.
Nonetheless, as presumed, it was either the female tears, or control group saline drops.
The researchers had all individuals participate twice, and it was to their finding that upon smelling female tears, they would more frequently choose to let the computer get away with stealing.
Findings of The Study
Upon drawing their conclusions, it was to the researchers’ newfound knowledge that aggression in the participants was reduced by over 44%.
They also found that this reduction of aggressive behavior was accompanied by neuronal changes.
Researchers observed participants’ brain post-tear sniff showed less activity in the prefrontal cortex and the left anterior insula, regions that are associated with aggression and decision-making.
Connectivity between the anterior insula and amygdala increased as well.
This region is responsible for emotional processing and is a part of the olfactory network as well.
One of the researchers furthermore explained,
“Working with colleagues at Duke University, the team used molecular biology methods to test the effects of tears and saline on 62 human olfactory receptors in a lab dish. They identified four receptors that responded to tears but not saline. This finding helps to answer ‘a major question’ about how pheromonelike signals are processed in humans.”
Shani Agron from PLOS Biology Research Journal
Conclusion
The same team who conducted the study for the effect of female tears on male participants, would like to in the future work on some similar projects.
Sobel talked about an interest with fellow colleagues in testing the effect of women’s tears on other women.
Meanwhile, Sobel would also be interested in potentially seeing whether the tears of babies have any effect on adult human beings.
He hypothesizes that it is almost intuitive that they would have said effect.
“Babies cannot communicate with you in language,” he says. “But evolution may have provided babies with this tool to lower aggression.”
Many researchers hypothesize why this may even be why we continue to cry into the turn of adulthood.
Agron alludes that crying must be a behavior that serves for us all throughout life.
Whatever the purpose of crying may be, we appreciate the hard work of researchers who worked on these projects.
Otherwise, we would know this little fun fact.
