Why We Cry – Tears Are Built to Stick to Our Skin

November 13, 2016

why-do-we-cry

Some of us having been doing a fair amount of crying this week. Our candidate lost. Leonard Cohen died. And last night Saturday Night Player, Kate McKinnon, sings Hallelujah, and channels Leonard Cohen through the image of our losing candidate, Hillary Clinton.  If you look at the above frame from the end of Cohen’s  song, Hallelujah,  you can see the tears in Kate McKinnon (as Hillary Clinton’s) eyes.  But why was Kate McKinnon  crying? Why do any of us cry?

Did you ever notice how long it takes for a tear to roll down a cheek? According to new research, an emotional tear (clinically known as the psychic tear) appears to be stickier than any other kind of tear. This is not only about loss or sorrow. An emotional tear is triggered by a wide range of feelings—from empathy, surprise, laughter, and joy to  anger and grief. The stickiness of the emotional tear is central to the newest thinking about the science of crying. Though some other species shed tears reflexively as a result of pain or irritation, humans are the only creatures, outside  from some elephants and a few dogs,  whose tears can be triggered by their feelings.

There’s a surprising dearth of hard facts about so fundamental a human experience. Evidence is mounting, however, in support of a relatively new theory – emotional tears trigger social bonding and human connection. While most other animals are born fully formed, humans come into the world vulnerable and physically unequipped to deal with anything on their own. Even though we get physically and emotionally more capable as we mature, grownups never quite age-out of the occasional bout of helplessness. “Crying signals to yourself and  to other people that there’s some important problem that is at least temporarily beyond your ability to cope,” says Jonathan Rottenberg, an emotion researcher and professor of psychology at the University of South Florida.

There are three major types of tears: basal, reflex, and psychic explains Joseph Stromberg of the Smithsonian College of Arts and Sciences. Basal tears are released continuously in tiny quantities to keep the cornea lubricated. Reflex tears are secreted in response to an irritant, like dust, onion vapors or tear gas. The psychic tear is initiated by a wide range of extreme feelings, whether positive or negative.

All tears contain organic substances including enzymes, lipids, metabolites and electrolytes. But the psychic tear has much more protein than the other two types. One hypothesis is that this higher protein content makes emotional tears more viscous, so they stick to the skin more completely and run down the face more slowly, making them more likely to be seen by others.

Tears also show others that we’re vulnerable, and vulnerability is critical to human connection. “The same neuronal areas of the brain are activated by seeing someone emotionally aroused as being emotionally aroused oneself,” says Michael Trimble, a behavioral neurologist at University College London and the foremost expert in the sciences of tears. “There must have been some point in time, evolutionarily, when the tear became something that automatically set off empathy and compassion in another. Actually being able to cry emotionally, and being able to respond to that, is a very important part of being human.”

“We learn early on that crying has this really powerful effect on other people,” Rottenberg says. “It can neutralize anger very powerfully,” which is part of the reason he thinks tears are so integral to fights between lovers—particularly when someone feels guilty and wants the other person’s forgiveness. “Adults like to think they’re beyond that, but I think a lot of the same functions carry forth,” he says.

The research on psychic tears is still in its infancy, but the mysteries of tears—and the recent evidence that they’re far more important than scientists once believed  Ad Vingerhoets , PhD, a psychology professor at Tilburg University in the Netherlands drives a small cadre of tear  to keep at it.

In times like this, after a week of loss and sorrow, a lot of us simply need to cry. I so doing, we and others  share our aloneness. “Tears are of extreme relevance for human nature,” says Vingerhoets. “We cry because we need other people.”