More than ten years have gone by since I last saw Stephen, but I can still recall his wound, a gunshot that went straight through his very soul. Stephen was a rowdy teenager from a small town, a difficult youth who played a dangerous joke on himself one night and wound up a completely different person. I was the senior neurosurgery resident in an urban trauma center when Stephen was rolled through the doors of our emergency room. The junior resident roused me from my slumber that night and summoned me to the ct room to review the boy’s case and to see his scans. Believe it or not, this was supposed to be a practical joke, the junior moaned as he yanked the still-warm films from the automatic developer. Together we studied the fresh X-ray images, the tiny black-and- white snapshots of a shattered brain. Yeah, the junior shook his head in disbelief and continued his monologue, a dumb, stupid prank. The boy’s named Stephen, barely fifteen and a real problem child, a ‘bad seed.’ He’s been treated for alcoholism and already owns a long string of juvenile arrests. The parents are divorced, and the father now has custody. Tonight, when Dad’s out working, Bad Seed and one of his pals get drunk and stick a single bullet into the father’s .22-caliber handgun, positioning the chamber where they thought it wouldn’t fire. The friend says they were just trying to scare Daddy. Nice, huh? Too bad they didn’t understand revolvers. When Dad comes home, the boy places the gun barrel against his right temple and--blam! With the first click he plants a slug in his brain. I listened to the junior’s sad tale with only half an ear. After several years of trauma call, I had learned it was best to ignore why people end up with bullets in them--that was a question for psychiatrists and juries, not acute-care physicians. Our job was to figure out how to undo a bullet’s devastation. Unfortunately, when the brain is the target, treatment options are often few. Just as a clapper striking a bell causes sound waves to resonate, a bullet entering the skull sets up sonic vibrations within the cranial vault, which in turn send shock waves tearing through gelatinous brain matter. A sufficiently powerful projectile will vibrate the whole brain to a pulp even if it barely passes through the brain’s substance. In this era of increasingly powerful street weapons, a surgeon often has little to offer victims who have been shot in the head, save for verifying the moment of legal brain death and notifying the organ procurement teams. Stephen was an exception, however. The bullet--low velocity and small caliber--had left him not only alive but semiconscious. His ct scan disclosed that the bullet’s blast had shattered his right front skull, blowing it inward; beneath the fracture a small blood clot was forming. Bits of metal marked the bullet’s path--showing up as white flecks, like the bread crumbs Hansel and Gretel dropped in the woods. The bullet had entered Stephen’s right temple, tearing through the front of the brain--the rounded projections called the frontal lobes-- before lodging in the boy’s left forehead. The white matter in the foremost frontal lobes, the so-called prefrontal areas, had been disrupted on both sides of the brain. Decades ago, people calling themselves psychosurgeons purposefully inflicted such frontal lobe mayhem in patients deemed mentally infirm. Their goal was to control the impulses of people who were otherwise uncontrollable, and their instrument for this elective mind mutilation was, incredibly enough, a modified ice pick. The pick was forced through the eye sockets and then moved around in the frontal lobes. The procedure was called a lobotomy, and the result was a permanent change in temperament. Stephen, however, elected to use a more precise method of psychosurgery: with a bang and a flash of powder, he appeared to have performed his own perfect lobotomy. But I wouldn’t know the extent of his brain damage until he recovered. I had Stephen brought to the operating room that night to remove the debris from his shredded brain. Although I would use a high-speed air drill and other modern surgical instruments, my planned operation differed little from battlefield procedures performed centuries earlier. Surgeons now work in ultraclean rooms disturbed only by the hissing of ventilators, but our heritage lies on manure-strewn fields laden with screaming, hemorrhaging men. Historically, brain surgery is one of the youngest of all surgical subspecialties. But human beings have been spearing, hammering, and shooting things into one another’s skulls since the dawn of history. Given the wealth of opportunity history provided them, even the most primitive artisans deduced a few useful tricks for dealing with head trauma. They have used instruments such as chisels and trephines to bore holes in the skull to relieve pressure and remove debris. And they recognized the importance of keeping wounds clean. Nearly two thousand years ago, for example, the Greek writer Heliodorus advocated quick removal of bone, dirt, and hair from brain lacerations in the belief that this prevented complications of infections and seizures. In the OR, beneath my fiber-optic headlight, I was still little more than a battle surgeon sent to pluck the shards of earthly violence from the most divine of organs. Despite our vast progress--our microchip- generated images, our lasers, our fourth-generation antibiotics--we can’t fix a brain any better than Heliodorus could; we can’t make the circuitry work again. We pull tufts of hair and splinters of bone from the mind and call it surgery. Stephen’s scalp lay before me, freshly shaved and painted with iodine. I carved a semicircular incision into the exposed skin, then secured the bleeding edges with plastic clips. I then gently rolled the scalp flap down and away from the damaged right frontal bone, carefully tethering it to the surgical drapes with hooks and wires. The frontal bone resembled a car windshield thrust inward by a rock; thin cracks radiated away from the bullet hole. A circle of bone about the size of my palm was depressed almost half an inch below the rest of the skull. I drilled three quarter-size holes around the periphery of this imploded bone. I then inserted small, flexible rods into the holes. Using the rods as levers, I pried out the embedded skull disk, exposing the dura mater, the thick membrane that surrounds the brain like a sausage casing. Normally, the dura is white, but an underlying clot was staining Stephen’s dura a dusky blue. Macerated brain, muddy brown and the consistency of toothpaste, oozed from the dural rent marking the bullet’s entry. I extended the rent further with scissors and vacuumed away thick slabs of clot until I could see the surface of the frontal lobe. The outer layer of the brain, the cerebral cortex, is mesmerizing--it seems too porcelain-smooth and brilliant pink to be living tissue. A fine mesh of bright red arteries covers the brain’s surface, creating a pattern that resembles the lacy etchings on a dollar bill’s border. For all its unearthly beauty, however, the exposed brain leaves little doubt that it is alive. Swelling and contracting with each breath and pulsating in time to the beating heart, the healthy brain dances within the skull. But Stephen’s brain looked ill, his frontal lobe’s dance of life disrupted by the trauma. Instead of being a healthy pink, the exposed brain was swollen and purplish. I cleansed his brain of debris, suctioning in the wound’s depths with a thin rubber hose to remove bits of metal and bone. I then flushed a gallon of warm antibiotic solution over the exposed brain surface. I finished by suturing the wound closed, layer by layer. I discarded the contaminated fragment of frontal bone--it could easily be replaced with a piece of plastic later. That was provided, of course, that Stephen survived. His postoperative course was rough at first, but Stephen ultimately did survive. He slowly regained an ability to follow verbal commands, and he had no trouble moving normally, but he wouldn’t speak to anyone. His manner was flat and emotionless, and he paid little attention to the therapists who tried to coax him back into the world. Once we were sure his wounds had healed and his brain swelling had gone away, he was transferred to a rehabilitation center, where he would probably be treated for three to six months. A year later, Stephen came to our outpatient clinic. It was the first time I had seen him since he left the hospital. His speech had returned and his mind seemed intact. He had returned to school and was even doing reasonably well, at least when his record was compared with his dismal scholastic performance of the past. To his father’s delight and to my surprise, Stephen’s behavior had never been better. He no longer argued with his parents or teachers or had fits of rage. In fact, he showed little desire to do anything outside the house, good or bad, and that suited his father just fine. Even Stephen’s occasional urinary incontinence didn’t seem to trouble either the father or the son. I had examined lobotomized patients before, but these patients had been relics of a bygone era, victims of the far more extensive removals of frontal lobe tissue performed by surgeons in the 1940s. These patients seemed like robots to me, whereas Stephen appeared almost normal, or at least what I thought was normal. Of course, I didn’t know Stephen before he shot himself, so I pulled his father aside, out of the boy’s earshot, and asked for his opinion. Is he the son you knew before? The question took him slightly aback. No, not at all. His personality is completely different; his sense of humor isn’t what it was. No, he isn’t like he was before, he replied, adding in haste, but I like him better this way. Well, I remembered thinking to myself, whether you like him or not, the new Stephen is here to stay. On the thirteenth of September,1848, Phineas P. Gage, the 25- year-old foreman of blasting operations for the Rutland and Burlington Railroad, was preparing the ground to lay tracks in Vermont. The blasting technique involved putting explosive powder and fuse into a hole, covering the hole with sand, then lighting the fuse. But Gage happened to tamp the powder into the hole before the sand had been poured in. The tamping rod struck the powder, igniting it. The blast drove the rod through Gage’s head like a javelin, the inch-thick shaft entering under the left cheekbone and exiting through the top of the head. Incredibly, Gage was only momentarily dazed. In fact, he remained conscious enough to help get himself to a doctor. The doctor cared for Gage by trying to keep the wounded area clean and bandaged. After a series of near-fatal infections around the embedded rod, Gage recovered. Though the injury left him blind in his left eye, the physical wounds to his head eventually healed. His psychic wounds, however, did not. While he retained his speech, memory, and other intellectual faculties, Gage was forever a changed man. Previously sedate and responsible, he became capricious, irritable, and hopelessly profane. Once the most dependable of employees, the injured Gage could not hold a job. He became a derelict, a wanderer, and died in obscurity 13 years after his accident. The lesson of Phineas Gage, a man traumatically converted from saint to sinner, still haunts us. In this enlightened age, we readily accept that nerve cells govern our mundane actions--walking, talking, urinating. With a little prodding, we can even accept that neurons are responsible for the Sistine Chapel and general relativity. But what happened to Phineas Gage showed us that our sense of right and wrong, of moral restraint and societal convention, also derives from the brain, or, more specifically, the human frontal lobes. Stephen’s transformation was the reverse of Gage’s. Gage fell to damnation in an instant, while Stephen, like Saint Paul, was diverted from trouble’s path by a single, blinding flash. Different as their outcomes were, Gage’s tamping rod and Stephen’s gun were both aimed at the anatomic substrate of our individuality, our humanity. Descartes believed the soul resided in the pineal gland, a small, conical structure deep in the brain, below the frontal lobes. He was wrong by a mere six inches. After Gage’s injury, his friends remarked that Gage was no longer Gage. And to this day, Stephen is no longer Stephen. A walking, talking person still inhabits his body, but the old Stephen died on that night a decade ago, dead by his own hand, a victim of a botched game of Russian roulette. May he rest in peace. Wherever he may be.