Phineas Gage

Phineas Gage was a 25-year-old railroad foreman in Vermont who, on 13 September 1848, survived a 13¼-pound iron bar driven up through his left cheek and out of the top of his head. He spoke within minutes and lived for almost twelve more years. His doctor later wrote that his friends found him "no longer Gage": impatient, profane and unable to keep to his plans^[2][8]. His case became the textbook example of the frontal lobe's role in personality, and then, over a century and a half of retelling, a source of myths that the evidence does not support.

This chapter follows the iron through his head on a 3D skull and brain, sets out exactly what his physician reported, compares three modern reconstructions of the damage, and checks the popular story against the records historians have since found.

13 September 1848§

Gage's crew was blasting rock to level the bed of a new railroad. The routine was to drill a hole, pour in gunpowder and a fuse, cover the powder with sand, and pack the sand down with a tamping iron. Gage's iron was made for the job: round, smooth with use, 3 feet 7 inches long and 1¼ inches across, weighing 13¼ pounds, and pointed at one end^[2]. Twenty years later Harlow added that the point tapered over about twelve inches to a quarter of an inch^[8].

The powder went off while the iron was in the hole. Harlow's first report, published that December in the Boston Medical and Surgical Journal, says the iron struck "against the left side of the face, immediately anterior to the angle of the inferior maxillary bone" (the lower jaw), and "made its exit in the median line, at the junction of the coronal and sagittal sutures"^[2]. On its way it passed behind the left eye^[7]. It was found some rods away, "smeared with brain"^[2].

What happened next is the part that made the case famous before anyone thought about personality. Gage was thrown onto his back, made "a few convulsive motions of the extremities," and "spoke in a few minutes." He rode sitting up in an ox cart for three quarters of a mile to his lodgings, and walked up a long flight of stairs with a little help^[2]. He lost the sight of his left eye^[5]. Over the next three weeks he lay mostly semi-comatose and fought an infection that formed an abscess under his forehead^[2]; about ten weeks after the accident he was well enough to go home to his family in Lebanon, New Hampshire^[8][9]. documented

The path of the iron§

The figure at the top of the page puts Harlow's landmarks on a schematic head. The entry is low on the left cheek, under the cheekbone and in front of the jaw; the exit is at the top of the forehead, at the back of the frontal bone, near the midline and the coronal suture^[8]. A straight line between them passes behind the left eye socket and climbs steeply through the front of the left hemisphere. Slide Push the iron back to zero and forward again: the red channel grows only where the iron has been, and the wire skull marks the bones it went through.

The line matters because it settles what the iron could and could not have hit. It passes well in front of the motor cortex, which is why Gage was not paralysed. It stays far from the brainstem, so breathing and heartbeat were never in danger. And it runs almost vertically, close to the midline at its upper end, which is where the argument starts.

Gage's skull has been studied three times with modern imaging, and the answers differ.

Damasio and colleagues, 1994. Hanna Damasio's group at the University of Iowa measured the skull, fitted it to a modern brain, and modeled the trajectories the iron could have taken. They concluded that "the damage involved both left and right prefrontal cortices," in a pattern that, in modern patients, impairs rational decision making and the processing of emotion^[3]. This version entered many textbooks.

Ratiu and colleagues, 2004. Peter Ratiu's group at Brigham and Women's Hospital in Boston worked from a thin-slice CT scan of the skull itself, reconstructed in three dimensions, and checked it against the physical skull and against Harlow's clinical notes. They noted that most physicians had believed the injury to be largely bilateral, and argued that previous studies had overlooked details of the fractures. Their result: the injury "was limited to the left frontal lobe, did not extend to the contralateral side, did not affect the ventricular system, and did not involve vital intracranial vascular structures"^[4].

Van Horn and colleagues, 2012. John Darrell Van Horn's group at UCLA recovered the 2001 CT data, modeled the iron at its measured dimensions (110 cm long, 3.2 cm across), posed the jaw open as Harlow's account requires, and passed it through the brains of 110 healthy volunteers, reconstructed from MRI and warped to fit Gage's skull. The best-fitting trajectory "did not result in the iron crossing the midline." On average it cut through about 4 percent of the cortical gray matter (3.97 ± 0.29 percent) and about 11 percent of the white matter (10.72 ± 5.46 percent), mostly in the left frontal lobe, with smaller damage to the left temporal pole and the insula^[7]. contested

The Van Horn study added something the skull alone could not show. Because the iron passed through white matter, it cut many of the long fiber bundles that connect the frontal lobe to the rest of the brain, including the uncinate fasciculus, the cingulum bundle and the superior longitudinal fasciculus, and so damaged connections in both hemispheres even though it destroyed cortex in only one^[7]. On this view, Gage's injury was as much a disconnection as a hole.

What Harlow reported§

Almost everything we know about Gage's behavior comes from one man. Harlow's 1848 paper is about survival: the wound, the treatment, the fact of recovery. Harlow's own description of a changed personality appears in his second full report, read to the Massachusetts Medical Society in 1868, twenty years after the accident and seven years after Harlow believed Gage had died^[8].

In it, Harlow wrote that Gage's employers had regarded him as "the most efficient and capable foreman in their employ previous to his injury," and that afterwards "the equilibrium or balance, so to speak, between his intellectual faculties and animal propensities" seemed to have been destroyed. His employers "could not give him his place again." He was "fitful, irreverent, indulging at times in the grossest profanity (which was not previously his custom)," impatient of advice that conflicted with his wishes, and full of plans that he abandoned as soon as he made them. "A child in his intellectual capacity and manifestations, he has the animal passions of a strong man." His friends and acquaintances said he was "no longer Gage"^[8]. documented

That is a vivid description, and a short one. Harlow gives no examples of specific incidents, no dates, and no description of how long the change lasted. Most of what later writers added to it (drinking, brawling, cruelty, years of drifting) does not appear in his reports at all. The historian Malcolm Macmillan, who spent decades collecting every account of the case, found that retellings grew more extreme with time, each adding detail with no source behind it^[6].

What happened next§

Harlow's 1868 paper also contains the bare outline of Gage's later life, and Macmillan and others have since filled it in from records Harlow never saw^[6][9]. Before you look at it, a question.

After his old employers would not take him back, Gage spent about a year traveling with his iron, showing himself and it in New England towns and, Harlow says, at P. T. Barnum's museum in New York^[8][9]. Then, for about a year and a half from early 1851, he worked with horses at a livery stable in Hanover, New Hampshire^[9].

In about 1852 he went to Chile to work for a man setting up a line of coaches at Valparaíso, and he stayed for about seven years, often driving a coach "heavily laden and drawn by six horses"^[8]. Macmillan reconstructed what that meant: the run from Valparaíso to Santiago was about 110 miles and 13 hours, starting at 4 in the morning, with fares to collect, luggage to manage and passengers to keep in order^[9]. A physician who knew Gage in Chile, Henry Trevitt, reported him "in the enjoyment of good health, with no impairment whatever of his mental faculties"^[9].

Around 1859 his health failed, and he left for San Francisco, where his mother and sister lived^[8]. He worked on farms, began having seizures in February 1860, and died in San Francisco after a series of convulsions on 21 May 1860. Harlow gave the year as 1861; burial records show it was 1860^[9][6]. No autopsy was done^[8]. Several years later, at Harlow's request, the grave was opened and Gage's mother and friends sent the skull, with the iron, to Harlow, who deposited both in the museum of Harvard Medical School, where they still are^[8][7].

Macmillan and Malcolm Lena's reading of this record is that Gage made "a surprisingly good psychosocial adaptation to his injury," and that the highly structured work of a coach driver, with a fixed route, fixed times and a sequence of tasks that had to be done in order, did for him what modern rehabilitation tries to do for patients with frontal-lobe injuries^[10]. The change Harlow described may have been real and severe in the first years and much less so later. documented

Myths and the evidence§

What the case taught, and what it did not§

Gage's case arrived at a time when it was not settled whether the brain had separate parts for separate jobs at all. A man who lost a large part of one frontal lobe and kept his speech, his movement, his memory and his senses, while something about his conduct changed, was evidence that the front of the brain does something different from the rest, and that what it does has to do with how a person behaves. Modern textbooks still describe the prefrontal region in those terms: planning, short-term memory and the cognitive functions on which personality is built^[12][1]. established

The case cannot carry much more weight than that. It is one person, described in detail by one physician, two decades after the event, with no autopsy and no examination of the brain itself. We know where the iron went far better than we know what it did: the bones have been scanned three times, while the behavior rests on a few paragraphs. The reconstructions agree that the damage was in the frontal lobe, mostly or entirely on the left, and that the fiber pathways linking the frontal lobe to the rest of the brain were cut^[4][7]. They cannot tell us how much of Gage's change came from the lost cortex, how much from the lost connections, how much from the seizures that eventually killed him, and how much was later, slowly, repaired.

The record of his later life may be the case's most useful lesson. A brain that has lost part of a frontal lobe is not frozen at the day of the injury. With time and the right circumstances, Gage seems to have rebuilt a working life^[10]. That is a more hopeful story than the one usually told, and a better-documented one.

This page is history and anatomy for education, not medical advice. Anyone with a head injury, or caring for someone with one, should get medical care; the outlook for frontal-lobe injury today depends on many things that this case cannot tell you.