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Read from Thumbs:


Howls, Hoots, and Calls

The Creature That Weeps

The Language of Lips


Walker Books

About Thumbs, Toes & Tears

And other traits that make us the strange and remarkable creatures we are It's not the howling itself that makes our crying unusual; it is the tears that go along with it. Other animals may whimper, moan and wail,but none sheds tears of emotion-not even our closest primate cousins. Apes do have tear ducts, as do other animals, but their job extends only to ocular housecleaning, to bathe and heal the eyes. But in our case, at some point long ago, one of our ancestors evolved a neuronal connection between the gland that generates tears and the parts of the brain that feel, sense and express deep emotion.


From Chapter 9 -"The Creature That Weeps"

"Why the heck do people cry? It is such a weird thing to do. You get upset and water comes out of your eyes."
-James Gross , Clinical Psychologist, Stanford University

"The advantage of the emotions is that they lead us astray."
-Oscar Wilde

.The very first thing a baby does when he enters this world is cry. It is a primal, unmistakable announcement that he has arrived. The birth cry signals two simple things: the child is alive, and the umbilical cord can be safely cut, which marks us as a whole and separate human being. During the first three to four months of life, before we learn to smile or laugh, crying is the primary communication method we have. But between eight and twelve months, we begin to cry less as we develop other ways to express what we want - by pointing or grunting, or tossing spoons, cereal and bottles around. But in our earliest days, we use it often and with great effectiveness.

An infant's cries are so effective partly because parents' ears are attuned to the bawling of their children. Nature has rigged it this way. Human mothers can almost always distinguish the cries of their own infants from the cries of others. Babies even have different cries that send different messages -- shrieks and screams of pain that mean something is seriously wrong, or cries of separation, discomfort and hunger. Each cry becomes a kind of rudimentary, wailing vocabulary that precedes a baby's first words. In fact, some linguists have theorized that the rhythmic rising and falling pitch of an infant's cries form the basic intonation pattern for all human sentences, which normally begin on an ascending note and then end on a descending one. When these cries are combined with the pained, reddening, puckered faces that often go with them, the two can garner a lot of very focused attention. (This face, it turns out, resembles the "frustration-sadness," "whimper," and "cry" faces of apes. )

As we grow older our reasons for crying become invested with more subtle shades of feeling. Our pain and discomfort is no longer simply physical, but emotional. And it is almost always inexplicable. We cry, it seems, because our emotions have outflanked the simple syntax of speech. Nouns and verbs and adjectives, and the logic that goes with them, simply aren't up to the job of explaining our feelings. If we could use words, we might not need to cry at all. But, of course, we do because crying, like laughter, is a primal form communication that taps the emotional, wordless and unconscious parts of our brains and experience.

In fact, electromyographic studies show that the nerves that operate the muscle that makes our chin quiver when we are on the verge of tears (the mentalis muscle), or that put the lump in our throats or depress the corners of our lips (depressor anguli oris muscle) are all very difficult to consciously and purposefully control. Yet the slightest disappointment instantly reveals itself in the expression of down-turned lips. In fact our mentalis muscle never really stops moving which is another way of saying it is an entirely unconscious physical representation of our emotions. These nerves and muscles simply don't check in with the verbal and conscious parts of our mind before doing what they do. This is why even when babies are born without structures above the mid-brain they can still cry, an indication that the feelings associated with crying run deep into our evolutionary history, long before the apparatus of speech and conscious thought emerged. .

.Tears do not consist entirely of water; they are actually a kind of "fluid sandwich" made of three separate layers. The inner layer, the part of the sandwich that bathes the cornea, or lens of the eye, consists of a lubricant called mucin. The middle layer is mostly water and the outer layer, over which the lids of our eyes fold is made up of oils evolved to keep our tears from evaporating. If our tears were not incessantly lubricating and cleansing our eyes, we would quickly and painfully lose them to infection and disease.

Just as our tears have three layers, tears themselves come in three varieties: basal, reflex and psychic. Each is unique in its purpose and its chemistry. Reflex tears that form when we get shampoo or a grain of blown sand in our eye, are produced automatically in the main lacrimal gland to flush the eye and help heal any damage. Basal tears stream continuously over our eyes so we can see clearly, and they dampen and remove dust and debris. Psychic tears are the ones that confound scientists. They well up when we experience strong emotion, mostly sadness it seems, but also when we feel intense pride, anger, frustration, or love and warmth.

Whatever the reasons for our tears, they all flow from the same intricate lachrymal system -- canals, glands and nerves with otherworldly names like the Glands of Zeis, or the Crypts of Henle. The lachrymal gland itself produces most of the tears we shed when our eyes are irritated or we feel our deepest emotions. Basal tears drip continuously from a system of tiny glands at the top of the eye and combine with fluid from goblet cells, the glands of Manz and forty-six meibomian glands to create a complex plumbing system that keep our vision clear and eyes free of disease.

Most tears eventually find their way to the canals at the bottom of our eyes near the bridge of our noses where they then drain through the puncta, the lip of tissue at the edge of our eyes. From there they journey through the lacrimal sac, past the Valve of Hasner and into our nose, which explains why crying hard leads to runny noses.

The whole system, however, can only handle so much water. It empties tears at the paltry rate of a microliter and a half per minute, a droplet only slightly larger than the tip of a ballpoint pen. If we cry heavily, the system overflows and our tears well up and spill down our cheeks. And as it turns out, this is important because visible tears are crucially important to human relationships.

Scientists not only categorize the kinds of tears we cry according to their purpose or the events that cause them, but by their chemical make-up. Reflex tears, like basal tears, come loaded with globins and glucose, antibacterial and immunological proteins, urea and lots of salt. But emotional tears actually have a different chemical make-up. In fact the tears we cry when we are upset, as opposed to when we get a sharp stick in the eye, have 20 to 25 percent more proteins. They also have four times the amount of potassium normally found in blood plasma, and 30 times the concentration of manganese. Psychic tears are also loaded with hormones, adrenocorticotropic hormone (ACTH), for example, an extremely accurate indicator of stress, and prolactin, which controls the neurotransmitter receptors in the lacrimal glands that release tears in the first place. The strange thing is that prolactin is also the hormone that makes it possible for women to produce breast milk.

Scientists believe that these cocktails of hormones and proteins are linked to the moods, stresses, and emotions we often associate with crying. High concentrations of manganese, for example, show up in the brains of people suffering from chronic depression. Too much ACTH is an excellent indicator of increased anxiety and stress. And studies show that women - all of whom have higher levels of prolactin than men -- cry about five times as often. In fact women unfortunate enough to have inordinately high levels of prolactin also experience more intense hostility, anxiety and depression, which can lead to still more crying.

There's another perplexing connection between prolactin and tears: when the child of a breastfeeding mother cries, the mother's milk reflexively "lets down" so that it becomes immediately available to the baby. In other words, the mother's body instantly and reflexively prepares itself to relieve the infant's reason for crying, or at least the most likely one. Some mothers even claim to experience a kind of telepathy with their infants; times when their milk lets down even when they are traveling or at the office running a meeting miles away from their infants. They report that on checking in later that their milk let down at precisely the time their baby started to cry.

Just as different reasons for crying result in chemically different tears, different parts of the brain -- the seat of our experience -- are physically connected to the feelings that make us cry. That is exactly the case. Nerves linked to our lacrimal glands rope their way by long roundabout routes into both ancient and newly evolved areas of the brain -- the pons, basal ganglia, thalamus, hypothalamus and prefrontal cortex. Each of these areas are themselves important cerebral routing stations that handle functions and experiences as diverse as facial expression, breathing, body temperature, sight, swallowing, and reflection, memory, planning and worrying. So it is no accident that so many kinds of feelings can cause us to cry. Nor is it an accident that those feelings affect our body temperature and blood pressure, heart rate and facial expressions, at the very same time they evoke more memories and emotions -- many of them confusing and contradictory.

When we cry, some of the hormonal cocktails that are driving the feelings we experience actually find their way into our tears. A biochemist named William Frey, who directs the Dry Eye and Tear Research Center in Minneapolis, believes one of the reasons we feel better after we weep is because we are literally crying out the extra hormones and proteins in our brains that generate the feelings that saddened us in the first place. This explains why, he says, we sometimes advise one another to, "Go ahead. Have a good cry." Emotional tears are the body's way of flushing out the chemicals that makes us sad -- the excess prolactin, manganese and ACTH.
That's one theory, anyhow. But not everyone agrees. If, for example, you find yourself crying over the death of a close friend as you recall the good times you shared, scientists wonder if it is your memories generating the hormones that make you sad, or the other way around? There is no absolute way to know. It may be both since, in effect, the brain is a tremendously complex feedback loop (hundreds of millions of loops within loops, really) that continually interact with the world outside and its own kaleidoscopic experiences inside. Perhaps feelings generate hormones and hormones generate more intense feelings until we finally burst into tears.
Randolph Cornelius, a psychologist at Vassar College, has been investigating the profound emotions that emerge out of crying's intricate neuronal alchemy since he began researching his doctoral dissertation some 25 years ago. During the earliest days of his work he asked subjects he was studying one simple question: tell me about the last time you cried in front of another person? The heartbreaking and harrowing accounts of life at its extremes often brought him to tears himself at the end of the day.

There was the young woman, for example, who told him of the day when she was barely 19, standing in a hospital with her six-month old infant in her arms, and gave doctors permission to remove life support for her husband, who was dying of cancer and had suffered a heart attack. She held her tears, she told Cornelius, until she had signed the papers, and then fell apart in the arms of a nurse whose name she never knew.

During another interview a Vietnam veteran told how he had had half of his face shot away during a firefight in Vietnam. He lost an eye and had a metal plate implanted to replace the portions of his skull that had been shattered. One day, he told Cornelius, he made a call to his therapist. He planned to leave a message telling her that he was committing suicide. She unexpectedly answered the phone and in the conversation that followed, he had a major breakthrough. When he did, he told Cornelius, he could feel "hot tears rolling down his cheeks."

A powerful sense of empathy and sympathy is a uniquely human reaction to the tears of others. Crying often begets more crying. Possibly because the mirror neurons that long ago made it possible for our ancestors to learn how to make a tool also enable us today to put ourselves into one another's shoes emotionally.

This makes human crying an unusually potent form of communication. More than anything, tears reveal us at our most vulnerable. Laughter bonds us, and it can bring us progressively closer, but crying binds us in another, deeper way: it is an unmistakable plea for help, an expression of utter vulnerability Tears in some intense and commanding way, communicate an opportunity for intimacy and authenticity that is more powerful than any words could be. When we cry, the walls are down, and the defenses have been breached.

. In 1975 an Israeli biologist, Amotz Zahavi, conceived an interesting theory about why animals behave, on the surface at least, in ways that don't seem to have much evolutionary purpose, but on closer observation turn out to be perfectly sensible. Many of these behaviors, he pointed out, seem not only baffling, but often downright counterproductive. Why does a peacock have enormous, colorful tail feathers when the natural result of having them must be that it slows the bird down, draws the attention of predators and makes it difficult to fly? Or why does a gazelle when it senses a lion is about to attack, bound straight up into the air like a pogo stick before making its exit?

Zahavi calls these traits and behaviors examples of the "handicap principle." We see them everywhere in the natural world from the huge antlers of bull elks to the loud squawking of hungry baby birds. On the surface the traits make no sense for the simple reason that they come at a high price - they require energy and resources, and draw dangerous amounts of attention.
But according to Zahavi they also serve as powerful forms of communication. In fact, the bigger the handicap, the more powerful the communication. An antelope's first vertical bound, for example, immediately puts it at a disadvantage. It has lost precious seconds it could have used to put distance between it and the predator that intends to make a meal of it. But a leap like that also sends a message that says, "I am so fast and can leap so high, there is no chance you are going to catch me. So don't waste your energy." Often the lion or cheetah poised for pursuit absorbs the message, performs a quick, primal cost-benefit analysis and walks away in search of more sickly prey incapable of a five-foot vertical leap.

In a strange way, messages like this have introduced a kind of primal form of truth and honesty into the natural world. They can't be faked because they are too costly. If a peacock could fake big, heavy tail-feathers and wasn't truly healthy enough to support them, it would quickly find itself a meal for any fox or wildcat that called its bluff. Those genes would not be passed along. The same would be the case if an antelope were capable of faking one bound, but was then unable to head off in the opposite direction at lightning speed. All of this is nature's way of saying, "If you can't walk the walk, don't talk the talk."

Being 'truthful" may explain the origins of our tears. Crying, like laughing is a unique form of human communication and its roots are just as primal. But unlike laughing, which we all do all of the time, crying is reserved for special occasions. That we don't often cry tears of emotion indicates that they come at a cost, a Zahavian handicap that requires extra energy or invites undue attention. Because tears are costly and rare, and because they are cried only when very deep emotions are being felt, they are not easily faked and send an unmistakable signal that the feelings behind them are absolutely real.

More often than not tears signal we want help and consolation because we are in pain - physical or emotional. But it also applies to feelings of pride or joy. When a father cries at the sight of his newborn baby and his wife sees this, it bonds them and says, in effect, "We are in this together." Cornelius has observed that our response to a person weeping tends to be profound, and reinforces the connections we feel for one another. Our hearts go out to people, even total strangers with whom we have nothing in common.

This cuts both ways, however. When we see someone crying, but we don't see any tears, we are immediately suspicious. Tearless crying simply isn't as authentic. Cornelius tested the dynamics of this too. Over the past six years he and his students have been gathering still photographs and video images from newsmagazines and television programs, all of them of people crying real and visible tears. When they found a particularly appropriate image, they prepared two versions: one, the original, with tears, and another with the tears digitally erased.

For this experiment they gathered a group of people and sat them down one at a time in front of a computer monitor to watch a slide show. Each slide presented two pictures, one tearful, the other a different picture with the tears secretly erased. No participants were allowed to see the same picture with and without tears. Cornelius' team then asked each participant to explain what emotion they thought the person in each photograph was experiencing, and how they would respond to a person with that particular look on their face.

The test's observers universally registered that pictures of people with tears in their eyes or on their cheeks were feeling and expressing deeper emotions -- mostly sadness, grief and mourning -- than those who were tearless. But when participants looked at pictures where the tears had been digitally removed, they often concluded that the people in them were feeling any number of emotions; from sadness to awe to boredom. Cornelius concluded that tears alone sent a specific and powerful emotional message.

But there was another wrinkle. The tearful pictures often elicited two very different responses from those who looked at them. About half of the observers felt people crying tears were saying, "Help me" or "Comfort me." The other half felt that the people in the images wanted to be left alone. This seems, says Cornelius, to have less to do with the expressions on the faces in the pictures and more to do with the attitude of the people looking at them. Sometimes crying is a call for help and attention, but sometimes it is a way of saying we are vulnerable and want room and space to deal with what is upsetting us until we can get back to normal. A contradiction? Not necessarily, says Cornelius. Trying to hide our tears still sends an honest signal about our state of mind. It still says we are in trouble, even want comfort, just not necessarily from someone else right at that time. Paradoxically, if someone refuses comfort or tries to hide their crying, it makes them seem even more vulnerable.

Tears carry a lot of expressive weight. If we evolved our outsized brains mainly to handle the complex social and personal interactions to which we pay tireless attention, then tears add one more true and powerful arrow to the quiver from which we draw our many forms of human communication.

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