A Natural History of the Senses (13 page)

An odd feature of touch is that it doesn’t always have to be performed by another person, or even by a living thing. Maternity Hospital in Cambridge, England, discovered that if a premature baby were just placed on a lamb’s-wool blanket for a day it would gain an average of fifteen grams more than usual. This was not due to additional heat from the blanket, since the ward was kept warm, but more akin to the tradition of “swaddling” infants, which increases tactile stimulation, decreases stress, and makes them feel lightly cuddled. In other experiments, snug-fitting blankets or clothes reduced the infants’ heart rate, relaxed them; they slept more often in their womblike bindings.

All animals respond to being touched, stroked, poked in some way, and, in any case, life itself could not have evolved at all without
touch—that is, without chemicals touching one another and forming liaisons. In the absence of touching and being touched, people of all ages can sicken and grow touch-starved.
*
In fetuses, touch is the first sense to develop, and in newborns it’s automatic before the eyes open or the baby begins to make sense of the world. Soon after we’re born, though we can’t see or speak, we instinctively begin touching. Touch cells in the lips make nursing possible, clutch mechanisms in the hands begin to reach out for warmth. Among other things, touch teaches us the difference between
I
and
other
, that there can be someone outside of ourselves, the mother. Mothers and infants do an enormous amount of touching. The first emotional comfort, touching and being touched by our mother, remains the ultimate memory of selfless love, which stays with us life long.

The little three-pound universe named Geoffrey, which I am stroking in long gentle caresses, has idly twisted his mouth and just as quickly untwisted it again. In other incubators around the room, other lives are stirring, other volunteers continue reaching in through portholes to help the infants begin to make sense of the world. The head research nurse of the ward, a graduate student in neonatal care, gives the Brazelton sensory test to a baby boy, who responds to a bright-red egg-rattle. Picking the baby up, she swings it gently around and its eyes go in the direction of the spin, as they should, then return to the midline. Next she rings a small schoolbell for ten seconds at each side, and repeats this four times. It is a very Buddhist scene. In a nearby crib, a preemie who is having his hearing tested wears a headset that makes him look like a telegraph operator. The policy with premature babies used to be not to disturb them any more than necessary, and they lived in a kind of isolation booth, but now the evidence about touch is so plentiful and eloquent that many hospitals encourage touching. “Did you hug your child today?” asks
the bumper sticker. As it turns out, this is more than a casual question. Touch seems to be as essential as sunlight.

Touch is the oldest sense, and the most urgent. If a saber-toothed tiger is touching a paw to your shoulder, you need to know right away. Any first-time touch, or change in touch (from gentle to stinging, say), sends the brain into a flurry of activity. Any continuous low-level touch becomes background. When we touch something on purpose—our lover, the fender of a new car, the tongue of a penguin—we set in motion our complex web of touch receptors, making them fire by exposing them to a sensation, changing it, exposing them to another. The brain reads the firings and stop-firings like Morse code and registers
smooth, raspy, cold
.

Touch receptors can be blanked out simply by tedium. When we put on a heavy sweater, we’re acutely aware of its texture, weight, and feel against our skin, but after a while we completely ignore it. A constant consistent pressure registers at first, activating the touch receptors; then the receptors stop working. So wearing wool or a wristwatch or a necklace doesn’t bother us much, unless the day heats up or the necklace breaks. When any change occurs, the receptors fire and we become suddenly aware. Research suggests that, though there are four main types of receptors, there are many others along a wide spectrum of response. After all, our palette of feelings through touch is more elaborate than just hot, cold, pain, and pressure. Many touch receptors combine to produce what we call a twinge. Consider all the varieties of pain, irritation, abrasion; all the textures of lick, pat, wipe, fondle, knead; all the prickling, bruising, tingling, brushing, scratching, banging, fumbling, kissing, nudging. Chalking your hands before you climb onto uneven parallel bars. A plunge into an icy farm pond on a summer day when the air temperature and body temperature are the same. The feel of a sweat bee delicately licking moist beads from your ankle. Reaching blindfolded into a bowl of Jell-O as part of a club initiation. Pulling
a foot out of the mud. The squish of wet sand between the toes. Pressing on an angel food cake. The near-orgasmic caravan of pleasure, shiver, pain, and relief that we call a back scratch.
*
On a cattle ranch some years ago, in birthing season, I helped the cowhands with the herd. Whenever we found a cow in trouble, someone had to reach into her vagina and check her condition. “You’re a female,” they’d invariably say, “you do it,” meaning that I was bound to know, by feel, the internal landscape of another female, even if she was only distantly related to me and her organs were horizontal. “Look for the two big boulders just over a rise …,” a Spanish-American cowhand had said helpfully on one occasion. Up to your shoulder inside a cow, you feel the hot heavy squeeze of her, but I’ll never forget my startled delight the first time I withdrew my hand slowly and felt the cow’s muscles contract and release one after another, like a row of people shaking hands with me in a receiving line. I wonder if this is how it feels to be born. Also, scientists have discovered that most of the nerve receptors will respond to pressure, as well as to whatever they specialize in. For the longest time we assumed that each sensation had its own receptor and that that receptor had its own pathway to the brain, but it looks now as if the body’s grasslands of neurons relate any sensation according to electrical codes. Pain produces irregular bleats from the nerves at jagged intervals. Itching produces a fast, regular pattern. Heat produces a crescendo as the area heats up. A little pressure produces a flurry of excitement, then fades, and a stronger pressure just extends the burst of activity.

After a while, as suggested, a touch receptor “adapts” to the stimuli and stops responding, which is just as well or we would be driven crazy by the feel of a light sweater against the skin on a cool summer’s evening, or go berserk if a breeze didn’t quit. This fatigue
doesn’t happen among the deep Pacinian corpuscles and Ruffini’s organs (joints) or the Golgi’s organs (tendons), which give us information about our internal climate, because if they nodded we would fall down midstride. But the other receptors, so alert at first, so hungry for novelty, after a while say the electrical equivalent of “Oh, that again,” and begin to doze, so we can get on with life. We may feel self-conscious much of the time, but we’re not often conscious of our physical selves, or we’d be exhausted in a typhoon of sensation.

Some forms of touch irritate and delight us simultaneously. Tickling may be a combination of the signals for, say, pressure and pain. Wetness may be a mix of temperature and pressure. But when we lose touch (the dentist gives you a shot of novocaine; an arm or leg falls asleep from lowered blood supply), we feel odd and alien. Imagine how frightening it must be to lose touch permanently. Touch loss can be maddeningly specific: A person loses a sense of temperature, or of pain. When my dentist gave me a shot of Carbocaine, my jaw dropped like a slab of pottery. I could still feel pressure and temperature—though the temperature sensation was reversed (ice water tasted like water but felt hot)—but I no longer felt any level of pain in the jaw. The absence of pain’s minute markers—a scratch, a pinch, a twinge—made the flesh feel cadaverous. In St. Louis, Missouri, one day a couple of years ago, I was going to a reading with novelist Stanley Elkin, who has suffered from MS for many years. Stanley could still drive, and we decided to take his car. But when we got to it and he went around to the driver’s door, he stopped and stood for what seemed ages, groping in his pocket. Finally he pulled out the entire contents of the pocket and set it all on the car hood so he could
see
his keys. Many sufferers of MS can feel an object in their pocket (a set of car keys), but they can’t identify it by touch. The brain won’t decode the shape correctly. As those who are simultaneously deaf and blind have shown, it’s possible to get on predominantly by touch, but to be without touch is to move through a blurred, deadened world, in which you could lose a leg and not know it, burn your hand without feeling, and lose track of where you stop and the featureless day begins.

It takes a troupe of receptors to make the symphonic delicacy we call a caress. Between the epidermis and the dermis lie tiny egg-shaped Meissner’s corpuscles, which are nerves enclosed in capsules. They seem to specialize in hairless parts of the body—the soles of the feet, fingertips (which have 9,000 per square inch), clitoris, penis, nipples, palms, and tongue—the erogenous zones and other ultrasensitive ports of call—and they respond fast to the lightest stimulation. Inside a Meissner corpuscle, like the many filaments inside a light bulb, branching, looping nerve endings lie parallel to the surface of the skin and pick up a wealth of sensation. Their parallel arrangement may make them especially sensitive to something touching them at a perpendicular angle. Furthermore, they are extremely specific because each area of the corpuscle can respond independently. As one researcher describes it, “It’s as though the receptor were composed of separate coils like an innerspring mattress; one can be depressed without disturbing the others.” What they record is low-frequency vibrations, the feeling of a finger stroking a beautifully woven sari, for example, or the soft angled skin inside another’s elbow.

The Pacinian corpuscles respond very quickly to changes in pressure, and they tend to lie near joints, in some deep tissues, and in the genitals and mammary glands. Thick, onion-shaped sensors, they tell the brain what is pressing and also about the movement of joints or how the organs may be shifting their position when we move. It doesn’t take much pressure to make them respond fast and rush messages to the brain. But they’re also adept with vibrating or varying sensations, especially high-frequency ones (a violin string, for instance); indeed, it may be the onionlike layers of the corpuscle that decipher differing vibrations so well. What the Pacinian corpuscles do is convert mechanical energy into electrical energy, as Bernhard Katz of University College, London, showed in 1950 in electrical experiments with muscles. Subsequent research has led to a better understanding of this process, as Donald Carr describes in
The Forgotten Senses:

Our menagerie of touch receptors also includes saucer-shaped Merkel’s disks, which lie just below the skin surface and respond to continuous, constant pressure (they give a sustained message, a continuous monitoring); various free nerve endings, which aren’t enclosed in capsules, and respond more slowly to touch and pressure; Ruffini endings, located deep below the skin surface, which register constant pressure; temperature sensors; cylindrical heat sensors; and the most familiar, but oddest, touch receptor of all: hair.

Hair deeply affects people, can transfigure or repulse them. Symbolic of life, hair bolts from our head. Like the earth, it can be harvested, but it will rise again. We can change its color and texture when the mood strikes us, but in time it will return to its original form, just as Nature will in time turn our precisely laid-out cities into a weed-way. Giving one’s lover a lock of hair to wear in a small locket
*
around his neck used to be a moving and tender gesture, but also a dangerous one, since to spell-casters, magicians, voodoo-ers, and necromancers of all sorts, a tuft of someone’s hair could be used to cast a spell against them. In a variation on this theme, a medieval
knight wore a lock of his lady’s pubic hair into battle. Since one of the arch-tenets of courtly love was secrecy, choosing this tiny memento instead of a lock of hair from her head may have been more of a practical choice than a philosophical one, but it still symbolized her life-force, which he was carrying with him. Ancient male leaders wore long flowing tresses as a sign of virility (in fact, “kaiser” and “tsar” both mean “long-haired”). In the biblical story of Samson, the hero’s loss of hair brings on his weakness and downfall, just as it did for the hero Gilgamesh before him. In Europe in more recent times, women who collaborated with the enemy in World War II were humiliated by having their hair cut short. Among some orthodox Jews, a young woman must cut off her hair when she marries, lest her husband find her too attractive and wish to have sex with her out of desire rather than for procreation. Rastafarians regard their dreadlocks as “high-tension cables to heaven.” These days, to shock the bourgeoisie and establish their own identity, as every generation must, many young men and women wear their hair as freeform sculpture, with lacquered spikes, close-cropped patterns that resemble a formal garden maze, and colors borrowed from an aviary or spray-painted alley. The first time a student walked into my classroom wearing a “blue jay,” it
did
startle me. Royal-blue slabs of hair were brushed and sprayed straight up along the sides of his head, a long jelly roll of white hair fell forward over his eyebrows, and the back was shiny black, brushed straight up and plastered close to the head. I didn’t dislike it, it just seemed like a lot to fuss with each day. I’m sure my grandmother felt that way about my mother’s “beehive,” and I know my mother feels that way about the curly weather system which is my own mane of long thick hair. One’s hairstyle can be the badge of a group, as we’ve always known—look at the military’s crew cut, or the hairstyles worn by some nuns and monks. In the sixties, wearing long hair, especially if you were a man, often fetched a vitriolic outburst from parents, which is why the musical
Hair
summed up a generation so beautifully. The police, who seemed so clean-cut and cropped then, were succeeded by a generation of police in long sideburns and mustaches. But I remember at the Boston Love-in in 1967, my first
year away at college, hearing one young man say to a passing couple who ridiculed his ponytail: “Fuck you and fuck your hairdressers.” I also remember, in the fifties, walking out of my bathroom with my hair sprayed into a huge bubble. “What have you done to your hair?” my father demanded. “I’ve just teased it,” I said. To which he replied: “Teased? You’ve driven it insane.” I wear my curly hair au naturel these days, in a shag cut the French call
la coupe sauvage
(“the savage cut”), but its volume and faintly erotic unruliness bother my mother’s sense of propriety. To her generation, serious women have serious hairdos that are formal, sprayed, and don’t move. A few weeks ago, she phoned to warn me that professional women aren’t taken seriously if they don’t have a “wet set” (rollers, hair dryer, setting lotion, hair spray). Loose ends on one’s head signal loose ends in one’s life. From this point of view, which has been popular for ages, a woman grows her hair long but keeps it tightly controlled in a bun, under a hat or scarf, or with hair spray, and lets her hair down only in private at night.