Cry me a chemical reaction

 

Let’s set the scene: There is a room full of adults, everyone is socialising and chatting. An argument begins among some men, testosterone kicks in and a fight begins. Suddenly a female bursts into tears. This causes the fight to subdue.

But why does this make it stop?

Is it because people are empathic and generally nice?

But then what do those words even mean? What actually makes people be these things? Was it actually just them looking at her and feeling ‘sorry’ for her that made them calm down? Do we have as much control over our behaviour as we think?

Let’s delve in.

To start we need to know a little bit more about that liquid stuff that falls from our eyes - whether we are watching our friend get married, our pet just died, we sat for too long beside a smoky fire or just decided to cut a friggin onion. All of these things cause the same liquid to fall from our eyeballs in each scenario, right?

…  Righttttt…...?

Well not really.

Those things that we call tears can be split into three categories, basal tears, reflex tears and emotional tears. Basal tears are always in our eyes, they keep our corneas nourished and lubricated and keep dust and debris away, acting like a shield. Reflex tears are released in larger amounts than basal tears and come only when harmful irritants need washed away (the smoky fire and that goddam onion). Finally, we have emotional tears (the wedding and the dead dog), and this is where things get a bit more interesting. Emotional tears are thought to have additional hormones and proteins compared to the other two.

So, what are those hormones and proteins doing there, and what has this got to do with that crying lady and those fighting guys?

Well, according to a study published in 2023, the chemicals found within a woman’s tears are actually very successful in significantly reducing aggression in men. The results showed a shocking 44% drop in aggressive behaviour and testosterone in men that had been exposed to female tears, alongside a corresponding decrease in brain activity in the aggression-related regions of the brain.

So, let’s now go back to these questions,

‘Was it actually just them looking at her and feeling ‘sorry’ for her that made them calm? Do we have as much control over our behaviour as we think?’

We now know that the chemicals are playing a role, but surelyyy it’s still that human thing of seeing her and feeling bad which is actually causing some of that 44% drop?

Again…. Nope!

In the study, men played a video game which was designed to provoke aggression. Whilst playing, they were either exposed to the emotional tears of a female, or a saline solution. They were not told which they had been exposed to. The method of exposure? Smell. So, in this case, seeing and therefore ‘feeling sorry’ for the female, and rectifying behaviour accordingly, played absolutely zero role. That full self-control we have over our action’s thing is starting to look a little more hazy…

It also is not the first time the chemical make-up of tears has been reported to cause behavioural changes in species. Blind mole-rats* are known to cover themselves in their own tears to prevent attacks from aggressive males, and the tears of female mice and rats have been shown to strongly inhibit aggression in male mice. Interestingly, in the study regarding rats, they also tested the impacts of the tears from female rats which had been ovariectomized (ovaries removed) and the tears of male rats, on the aggression of other males. The tears of the ovariectomized female rats showed a significantly lower reduction in the aggression of the male rats compared to non-ovariectomized females, and male tears showed no impact at all.

So far, that’s pretty much all that we know. The impact of human male tears on female behaviour is yet to be studied (female tears and men reactions were chosen due to the rodent results). Scientists know about pheromones in other species, but this is basically as far as we’ve got with humans. It has been predicted however that there are many more chemicals released (in sweat etc., mmm), which further influence the behaviour of those around us, and that some people have the subconscious capability of producing them more than others.

So, are tears a weakness really? Or a strong defence mechanism and human control superpower? Much more to learn and think about it seems…..!!

 

*Not researched (due to the time & scope of this project 😉), but I think its pretty interesting it’s blind mole rats. I guess an increase in one defence mechanism to counteract for the lack of ability to present themselves as big and threatening etc?