The Pain Chronicles (4 page)

THE DESCENT OF PAIN

It’s a small space, a crevice over which tangled roots cross like hands. The deer takes an idle leap; her hoof falls through the lattice. She tries to leap again, but pain holds fast and her body quivers and falls. She pants, panicked, but the desire to flee is checked against pain. She tries to stand once again, but pain tightens its grip.

In the deer’s leg, sensory receptors known as
nociceptors
are activated in the basic process of tissue protection common to many multicelled creatures, from horses to earthworms. This process is known as
nociception
, from the Latin
nocere
, “to hurt or injure,” and the root
-cept
, which can mean “begin.” These receptors are, indeed, “the beginning of hurt,” responsible for sending nerve signals warning of a bodily threat.

Nociceptors register mechanical (crushing), chemical (poisons), thermal (burns), or other stimuli that have the potential to damage cells. The threshold for activating normal pain-detecting nociceptors is similar among all members of a species: in humans, for example, the pain threshold for heat is about 108° F. At a lower temperature, the water feels pleasantly warm, but right around 108° F the pain-detecting neurons activate and send an alarm.

Nociceptors are attached to two different types of nerve fibers, A-delta fibers and C fibers, which transmit information from the periphery of the body to specialized receptors in the spinal cord. A-delta fibers are nature’s warning alarm; they produce a fast, sharp, distinctly localized pain. Indeed, the information conveyed by the A-delta fibers doesn’t even need to reach the brain to have an effect; when the signals reach the nociceptors that sit in the spinal cord, they trigger an immediate muscular action that causes the creature’s body to move away from the harm. C fibers, on the other hand, are activated after the alarm has sounded and damage has already occurred. They produce a slow, persistent, diffuse pain that indicates continuing injury and forces the creature to tend to its wound after the danger has passed.

The other deer continue to trot, disappearing into the woods. Yet vast respiratory and cardiovascular changes take place in the injured animal as the brain stem reacts to news of the injury by activating the autonomic nervous system (the part of the nervous system that regulates heart rate, breathing, and so forth) and triggering a massive release of adrenaline and other hormones. The vital purpose of the hormones is to pump up the immune system and help the liver and muscles produce and absorb more sugar, which will generate more energy to flee or fight. Rising heart rate and blood pressure prepare the deer to escape.

While danger causes the body to generate energy initially, the wounds—along with the subsiding of endorphins, adrenaline, and the other hormones—later create a sense of sluggishness to force rest. Pain activates the immune system as the injured tissue causes an inflammatory reaction that sensitizes nerves, which causes greater pain. White blood cells release substances that promote fever and sleepiness, helping healing by increasing blood flow to the area, consuming dead cells, and delivering nutrients to the site. The entire area becomes sensitized so that even a light touch there will hurt. This sensitivity is adaptive because it ensures that the site of the injury is protected and rested.

Pain also affects the hypothalamus, the part of the brain that controls hormone release, sleepiness, waking, hunger, thirst, and sexual drive. In the hierarchy of drives, pain is the highest—the most important to survival—so all other drives are stilled. As the feeling of agitation and alertness ebbs, the deer begins to feel heavy, warm, drowsy.

Each of these reactions—together composing the body’s response to grave wounds—is a product of a neurobiology millions of years in the making. The basic sequence of responses to pain is common across many species: vigorous activity to escape danger, combined with unresponsiveness to all other external stimuli, followed by guarding of the wound and lethargy during recovery.

There are also characteristic behavioral responses, such as repetitive motions (e.g., rocking to and fro), vocalization, grimacing, crying, or whimpering, which serve to warn others in the group of danger and to impress upon them the severity of the threat. Although human pain behavior seems designed to evoke care from others, when most animals are wounded, others of their species will instinctively keep their distance to let the injured member of the group heal. Moreover, the animal isolates itself from its own herd or family for fear its injury will be jostled. When a human comes near, it will try ever more frantically to escape. If the human tried to examine the leg, the deer would desperately thrash her head and kick with her other legs. If the deer were a fox or a wolf, she would bite.

If the deer were a worm who had just lost the tail of its body, it would slither away without a second thought—or, indeed, a first one. Nature endows even invertebrates, like sponges and leeches, with the damage-sensing nociceptors of mammals and the reflexes to withdraw from danger, but with one key difference: this stimulus-response is not thought to cause the invertebrate pain.

Since nature didn’t give invertebrates the thinking parts of the brain that would enable them to recall dangers and avoid them in the future, she also didn’t curse them with the apparatus of a central nervous system to make them suffer from their blunders. Instead, she gave the worm, like plants, spare or replaceable parts to cover mishaps. Anyway, nature (it feels unnatural to write about nature without personification) is not concerned with the worm’s death, because the worm has dozens—perhaps hundreds—of offspring.

The deer, on the other hand, is dear. Nature has a limited supply: deer produce few offspring, and they take a long time to mature. Mammals have no spare body parts and cannot grow new ones; a broken leg is the deer’s demise. So nature endows the deer with a cortex to generate pain to ensure that she will protect her leg.

Even fish have an efficient nociceptive sensory apparatus involving nerves, a spinal cord, and a primitive cortex to process nociceptive signals. Moreover, they respond with behaviors characteristic of animals with more complex cortices (like mammals) in pain, and these behaviors can be reduced by opiate pain medication. Still, pain involves not only detecting harmful stimuli but also having a negative psychological experience, and some researchers argue that the brain of a fish lacks the complexity that is necessary for consciousness. Pain requires—indeed, is
a function of
—consciousness: the greater the level of cortical development, the greater the capacity to feel pain. Fish have small, primitive cortices. Mammals’ cortices are much more complex than those of other animals, and primates’ are the most so. Moreover, only primates possess an
interoceptive cortex
—a part of the brain believed to be critical in pain perception. The human interoceptive cortex is greatly enlarged.

We, mammals with few natural defenses (lacking claws, camouflage, and saber teeth) and limited reproductive capability (having few offspring, who take many years to reach maturity), are the most closely guarded by a hypervigilant nervous system and a brain with special capacities for generating pain and turning it into a world of unhappy associations and emotions—of dread, loss, anguish, anxiety, regret, and suffering.

THEIR EYES WERE OPEN TO SUFFERING

A woman whose leg is caught in a crevice would feel pain commensurate with the threat the injury poses to her survival, just as a deer would. But as evening descends, another feeling would begin to set in. Although her brain would release the same neuropeptides that allow the deer to sleep off the pain, the woman would lie awake, contemplating this pain and its implications. What if no one comes to help her? She pictures the life that she had, and already it appears both near and impossibly far, like a garden from which she has been suddenly exiled. Along with fever, the sense of
‘etsev
(
—a Hebrew word with the various meanings of “hurt, pain, worrisome toil, pang, sorrow, hardship, forsakenness, grief, and affliction”), to which Eve was condemned, sets in. Her eyes are open to suffering.

The multiplicity of meanings of
‘etsev
reveals what is human about human pain: the way pain is always steeped in sorrow and other negative emotions (a result of a development, unique to humans, of certain kinds of neural bridges connecting the emotional, cognitive, and sensory parts of the brain).

Why?
the woman protests. Of course, she comprehends her situation in the same basic way the deer may (she fell; she was injured; she can’t get up). But we cannot picture a human for whom this explanation would fully suffice, because from ancient times onward, humans have also asked a question of a different sort—one that cannot be answered with reference to the material world, but rather that conjures a hidden world of meaning. The question is “why?” in the peculiar sense of “why
me
?”

This human
why—why is this my story and what story is this?
—does not seem to serve any evolutionary function. Yet the question is so universal, appearing across diverse cultures over thousands of years, as to seem genetically coded into the experience of prolonged pain, like inflammation and drowsiness.

Why must I suffer?
we ask haplessly, fearing the answer and fearing the absence of an answer. And the longer the pain persists, the more the question presses.

The deer’s stumble hurts her, but only the human falls into
‘etsev.

EVIL, HURTFUL THINGS OF DARKNESS

The same questions would pain a woman who fell in the forest today as a woman four millennia ago. The earliest records of history—the cuneiform tablets of ancient Mesopotamia—reflect the urgency to understand bodily pain: how to parse its spiritual significance and alleviate its physical consequences. If the injured woman were an ancient Babylonian stranded somewhere on the Mesopotamian plain, she would understand her pain and injury in a particular way, and indeed, the frame would not be that different if she were Sumerian, Akkadian, Assyrian, ancient Egyptian, Roman, Greek, or Indian.

If I were that woman, I would know that pain, illness, and death arise from a vast, invisible cosmological contest between the opposing malevolent and beneficent demons and deities that control the natural world and compete for domination over mortals. Hosts of demons could enter the body through the unguarded openings of the eyes, mouth, nostrils, and ears, where they would suck the marrow out of bones, drink blood, and devour organs until—save for the intervention of a benevolent deity—the victim perished. Protection could come only from the gods, who, though unreliable and inattentive, must be petitioned for aid. If I were a Babylonian, I would have a personal god whom I cultivated with prayers and offerings and invocations. “One who has no god, as he walks along the street, Headache envelops him like a garment,” warns a Babylonian fragment.

For the ancient Egyptians, the body was divided into thirty-six parts, each one the province of a particular god or goddess. In some traditions, demons shared their names with the specific maladies they inflicted. The ancient Indians were tormented by Grahi (“she who seizes”)—a she-demon who caused convulsions. For the Akkadians the D
’û demon caused headaches. Indeed, D
’û
was
headache—to have a headache was to be possessed by the demon, so there is no other Akkadian word for “headache.” In Babylonian texts, the words for “sin,” “sickness,” and “demon possession” are closely related and often used interchangeably.

How might I rid myself of these demons? In the ancient world, ritual magic could be used to dispossess demons, or pain could be transferred from one person to another. In Babylonia there was a special class of priest, called
gala-tur
, who could absorb an ailment from a living person and carry it into the netherworld and dispense it there. A suckling pig or kid could be sacrificed, and the demon could be transferred to the animal’s body. In some cases, expelling demons from the body called for graver measures, such as trepanation—drilling holes through the skulls of the sick to release the demons causing migraines as well as seizures and other ills.

While demons, ghosts, and other evil spirits were more common than gods, in most cultures the powers of the gods were superior. So although the gods could not eliminate the demons—who were also immortals—they could control them. I might turn to the Ebers Papyrus, a compendium of ancient Egyptian prescriptions, spells, and enchantments from 1552
B.C.E.
that is one of the oldest medical documents in existence, to find an invocation to the gods, imploring them to “free me from all possible evil, hurtful things of darkness.”

I would know, though, that unfortunately, pain and disease could arise directly from the gods themselves. Some gods were consistently adversarial, but most were mercurial and might be swayed by entreaties for assistance and dissuasion from harm. Arrows thrown by Rudra, the ancient Indian Vedic storm god, brought humans sudden pricks of sharp pain. But his hands also contained “a thousand remedies,” and his urine, the sacred element of rain, was an anodyne. The Greek god Apollo shot invisible arrows and spears at men, causing illness and death—sufferers were “Apollo-” or “sun-struck”—while his twin sister, Artemis, afflicted “Artemis-” or “moonstruck” women with female maladies. Yet Apollo was also known as a healer: sacred hymns that pleased him might lull him into ending plagues, while Artemis was also known as a goddess-physician, specializing in obstetrics and gynecology.

If I were a Babylonian, I would implore my personal god to lobby for me in the pantheon of gods, as in this invocation in which Marduk, the patron deity of the city of Babylon, consulted his father, the god Ea, about an innocent human victim: “Oh Father, Headache has set out from the Underworld . . . whatever this man has done, he doesn’t know it; however will he be relieved?”

Comfortingly, the gods themselves were vulnerable to pain and disease and used spells and curses to rid themselves of pain, which mortals could imitate for their own cures. For example, the Egyptian god Horus was tormented by catfish demons that caused him migraines so severe he sometimes resorted to living in the dark. The great sun god Ra (who suffered from eye diseases, which manifested as eclipses) helped Horus by threatening to cut off the catfish demons’ heads with his
tmmt
-loop, his sacred scepter. If I were suffering from a migraine and I incanted this story while my head was rubbed with a
tmmt
-loop made of snake, the demons might flee from me as well. Alternatively, the demon could be dispossessed by rubbing my skull with the ashes of the bones of catfish boiled in oil for four consecutive days.

I could read stories of cures of both gods and men on the walls of temples dedicated to the healing gods in ancient Mesopotamia, Egypt, Greece, and Rome. I might even sleep in the temple, undergoing purification rituals of fasting and bathing, and make an offering to the god or his animal representative. During the night, the gods might reciprocate by transmitting cryptic clues for cures in the form of opaque dreams, which would be interpreted by priests in the morning. If I were too ill to travel to the temple, my family or friends might make the pilgrimage on my behalf, as when Alexander the Great lay dying in Babylon and his generals slept in the temple of Marduk on his behalf. Evening rites often involved the use of opium, which would lull pain and induce vivid dreams for the priests to interpret. If a cure did not arise, I could continue to stay in the temple and further entreat the god. (Dying patients, however, having been scorned by the gods, would be cast out by the priests lest they pollute the temple.)

If I were Greek, I might sleep in the temple of Asclepius, the god of medicine, whose followers—priest-physicians, such as Hippocrates, who claimed to be his descendants—took an oath to heal, to cause no harm, and to keep secret their sacred medical knowledge, a pledge that may be a template for the modern Hippocratic oath. Statues of Asclepius often feature him with his symbol, a serpent-entwined staff that expressed the ancients’ belief in the twinning of divine help and harm—the intimate relationship between poisons and remedies, healers and destroyers. Even today, a version of the serpent-entwined staff survives as a symbol on ambulances and hospitals: an indirect tribute to the god—or plea, perhaps, for his protection—who, in the words of the fifth-century
B.C.E.
poet Pindar, “first taught pain the writhing wretch to spare.”

Words themselves could become medicine, as in the Egyptian practice of writing down an incantation or spell with edible ink, dissolving the letters in liquid, and then drinking it. But spells and incantations were often paired with natural remedies such as herbs, roots, or the testicles of an exotic animal, with which they worked synergistically. Babylonian tablets dating back to the third millennium
B.C.E.
detail how each ailment corresponded to a particular deity or demon and required an individual remedy. If I were a Babylonian with a toothache, I would know that it was caused by the sucking of a primal demon-worm. When the worm was first created, a god offered her some nice food to eat, but the worm rejected the food, saying, “What are a ripe fig and an apple to me? / Set me to dwell between teeth and jaw, / That I may suck the blood of the jaw / That I may chew on the bits [of food] stuck in the jaw.” The worm’s request was granted, but she was cursed for her bloodthirstiness. Invoking the curse by reciting the story of the worm’s creation three times over a poultice of beer, oil, and a (now-unidentifiable) plant and applying it to the tooth would cause the toothache to resolve.

As the Egyptian Ebers Papyrus explains, “Magic is effective together with medicine. Medicine is effective together with magic.” Although it would take millennia to understand why, magic
is
effective together with medicine and medicine
is
effective together with magic: words (when given the power of belief) do affect pain—and words in combination with physical treatment can alleviate pain in ways better than either treatment alone.