Phineas Gage, whose story is known as the ‘American Crowbar Case’, was an otherwise unremarkable man who unwittingly played a pivotal role in humankind’s understanding of the brain. In 1848, while working, 25-year-old Gage sustained a horrific injury to his brain. Miraculously, he survived, but his personality was altered to such an extent that his friends found him to be ‘no longer Gage’. He was thus a classic example of how specific parts of the brain affect behaviour and personality. An extraordinary recovery with unexpected side-effects Gage was a foreman clearing a path to build a railroad in Cavendish, Vermont, US. He would drill a hole and use a tamping iron – a 13-pound, hollow iron bar – to compact explosive powder into the rock for it to be set off. On 13 September, the metal bar, which hit the rock, creating a spark that ignited the explosives. That, in turn, “drove this tamping iron up and out of the hole, through his left cheek, behind his eye socket, and out of the top of his head,” says Jack Van Horn, associate professor of neurology at the Keck School of Medicine at the University of Southern California. This rod was later found lying “smeared with blood and brain”, some 30 yards away from Gage. Against all expectation, within minutes of the fateful incident, Gage was sitting up in a cart, conscious and recounting what had happened. Gage was left with much of the left frontal lobe of his brain destroyed, and found to be ‘fitful, irreverent, indulging at times in the grossest profanity, which was not previously his custom’, according to his attending doctor, John Martyn Harlow. A case that would leave its mark in medical history This sudden personality change made Gage a fixture in many medical textbooks, says Malcolm Macmillan, an honorary professor at the Melbourne School of Psychological Sciences. “He was the first case where you could say fairly definitely that injury to the brain produced some kind of change in personality,” Macmillan explained. This development helped establish neuroscience as a field, back in a time when virtually nothing was known about brain functions. “If you talk about hard core neurology and the relationship between structural damage to the brain and particular changes in behaviour, this is ground zero,” concurs Allan Ropper, a neurologist at Harvard Medical School and Brigham and Women's Hospital. It was an ideal case because “it's one region [of the brain], it's really obvious, and the changes in personality were stunning”. Gage’s case continues to be revisited by academics and researchers alike. Most recently in 2012, a team led by Jack Van Horn of UCLA’s Laboratory of Neuroimaging (part of the Human Connectome Project) used a combination of CT scans of Gage’s skull and MRI scans of typical brains to create a digital model of the rod’s path. The team found that up to 4% of Gage’s cerebral cortex and approximately 11% of the total white matter in his frontal lobe had been destroyed – the brain damage was more extensive than had previously been estimated. Moreover, the accident had compromised the connections between the frontal cortex and the limbic system, which regulate emotion. This supports some of the reports of Gage’s behaviour. The resilience of the human brain Not much is known about Gage’s life after the incident. Previously a ‘most efficient and capable’ foreman, Gage’s employers ‘considered the change in his mind so marked that they could not give him his place again’, according to Harlow. Nevertheless, Gage’s “personality change, … did not last much longer than about two to three years”, said Macmillan. It is known that Gage went on to become a long-distance stagecoach driver in Chile – a job that Macmillan observes to have required considerable planning skills and focus. It is important to recognise this development of Gage’s life for the powerful message it brings to present day patients. “Even in cases of massive brain damage and massive incapacity, rehabilitation is always possible,” says Macmillan. Gage lived for another 12 years before succumbing to an epileptic seizure on 21 May 1860, which was likely to be related to his brain injury. But his story lives on, though the way it has been told has changed. “In 1848, he was seen as a triumph of human survival. Then, he becomes the textbook case for post-traumatic personality change. Recently, people interpret him as having found a form of independence and social recovery, which he didn’t get credit for 15 years ago,” says Dominic Hall, curator of Warren Anatomical Museum, where Gage’s skull resides, along with the tamping iron that bore through it. Source