Читать книгу The Blue Man and Other Stories of the Skin - Robert A. Norman - Страница 10

PART ONE

OUR VITAL SKIN

Our skin mediates the most important transactions of our lives. Skin is key to our biology, our sensory experiences, our information gathering, and our rela-tionships with others. Although the many roles it plays are rarely appreciated, it is one of the most remarkable and highly versatile parts of the human body.

—Nina Jablonski, Skin: A Natural History

What is the function of the skin? It is the information source and processor. It is the foundation for sensory reception. It is a barrier between us and our environment. It is an immunologic source of hormones for protective cell differentiation. It protects our underlying organs from radiation and mechanical injury. It serves as a barrier to toxic materials and foreign organisms. It plays a major role in regulating blood pressure and the flow of blood. It performs regenerative repair. It works as a temperature regulator. It is involved in the metabolism and storage of fat, salt, and water. It serves as a reservoir for food and water and as a respiratory organ for the passage of gases. It is a synthesizer of important compounds including vitamin D. It forms an acidic barrier that protects us against bacteria.

On a morning walk, I stopped to speak with a city worker who was heading into a hole in the ground to service the water pumps. Given my insatiable curiosity, I had to ask him about how the system was hooked up and how our neighborhood water got pumped in. He was informative, with a good tour guide’s patience.

“I’m glad you asked,” he said. “Most of the time we only get bothered when something goes wrong.” He provided me with a mini-lecture about what lies beneath the city surface and how many things must be maintained in order to keep our rising demands for service satisfied.

Underneath our homes, sidewalks, and streets is a rapidly increasing mass of cables, pipes, and devices for the delivery and removal of water, electricity, data, natural gas, and sewage. Most of us have experienced the frustration of having a single one of these malfunction, as when a water line explodes or a utility line is cut.

Likewise, underneath the skin is a complex, intense system—one that outperforms any municipal system. Just as construction workers check and mark carefully before drilling, all of us who penetrate the body’s top surface must respect the boundaries of key structures and evaluate the anatomy prior to any invasive procedure. When treating people, we must consider a plethora of factors in order to provide comprehensive care, including personal and family history of disease; current medication use; social history including smoking, alcohol, and education; and the ability to pay for treatment.

The skin is a marvel. In the best circumstances, it heals itself, repairing and restoring its former integrity. It is grim in sorrow, radiates warmth in love, and shines in tranquility. The skin is an organ in and of itself, with its own personality, temperament, and particular eccentricities.

From a very early age, we use one sense the most—touch. When we reach out and touch an object that is too hot, an almost instantaneous event occurs. The temperature sensors in our skin send nerve signals running up the arm to the spinal cord and into the brain at over two hundred miles per hour. The brain interprets the sensation as pain and signals the hand muscles to move away, all before we can think.

Ashley Montagu in his book Touching: The Human Significance of the Skin focuses on what he calls the somatopsychic or centripetal approach, the manner in which tactile experience or its lack affects the development of behavior and “the mind of the skin.” He writes, “The skin, the flexible, continuous caparison of our bodies, like a cloak covers us all over. It is the oldest and the most sensitive of our organs, our first medium of communication, and our most efficient protector.”

The scale of these contributions is staggering. In a piece of skin the size of a quarter, more than three million cells, one hundred to three hundred sweat glands, fifty nerve endings, and three feet of blood vessels are at work. The skin comprises millions of cells of different kinds, some 350 different varieties per square centimeter. Huge numbers of touch, pressure, pain, heat, and cold sensory receptors live on the skin surface, particularly in the hands, face, and mouth. That’s why babies like to explore with their tongues: the tongue alone has more than nine thousand sensory receptors.

Montagu writes, “As the most ancient and largest sense organ of the body, the skin enables the organism to learn about its environment. It is the medium, in all its differentiated parts, by which the external world is perceived.”

The perception of the skin varies with each culture and time. The skin is considered a mirror of inner wellness in traditional Chinese medicine. In Greek mythology, the skin is a vulnerable shield. The modern, Western view increasingly recognizes skin as a permeable system, and recent research confirms that it has its own built-in, autonomous immune defenses.

We interpret skin as providing evidence for deeper problems, both bodily and psychologically. Our skin can torture us by disfiguring our bodies, but it also makes up the most basic facets of our social worlds. Without “normal” skin, we may find it hard to hold a job, feel self-esteem, make friends, or find love.

As Montagu writes, “On our skin, as on a screen, the gamut of life’s experiences is projected: emotions surge, sorrows penetrate, and beauty finds its depth. Soft, smooth source of youth’s vanity, skin later bears wrinkled witness to the toll of years. Radiant in health, it tingles to the affectionate touch.”

If I took all the patients I have seen and put them along an elastic spectrum, I could not stretch it far enough to encompass the contrasts in characters and skin that I have encountered. The differences within this multitude of humanity are as bright as the sunniest day and as dim as the prospects of a few of them rising above the genetic lottery.

During any given week I may see and treat a coal-black Nigerian boy who has barely learned to speak a bit of English; an old, world-worn Southern farmer with tiny islands of coral blue eyes in a sea of sun-damaged skin; a shoulder-stooped, bronzed Cuban man formerly a prisoner under Castro, his face sagging in depression and haunting memories; a homeless skinny black man, washing his feet in the exam room sink, specks of vitiligo everywhere on his skin, as if a dripping paintbrush had splashed randomly onto him; a red-armed backwoods white boy from Arcadia, dragged in by his sleepless mother because his skin has peeled off from eczema and he has missed most of the school year and scratched and hollered every night; a thin, slack-jawed, coffee-colored Haitian woman who arrived in Florida by boat in the middle of the night; and any number of those whose skin cancer or psoriasis or itching has gotten so out of control that they grab onto my office exam table like a buoy in the Atlantic during a hurricane and will not leave until they finally gain relief. In between may be visits with children who have warts or young men and women with acne, who recognize the relatively benign nature of their problems, and may even add some hope or levity to the day.