It's easy enough to understand the ghastly accident that befell poor Phineas Gage in Cavendish, Vermont on Sept. 13, 1848: the 25-year-old railroad worker was using an iron rod to tamp down blasting powder when the stuff exploded, sending the 43-inch-long, 13-pound rod through his left cheek and out the top of his head.
What's not so easy to understand is why Gage survived the accident--or the precise reason for the dramatic change in his personality afterward. John Harlow, the doctor who treated the once-affable Gage, wrote that he "could not stick to plans, uttered 'the grossest profanity' and showed 'little deference for his fellows,'" Smithsonian magazine reported in 2010.
But now researchers are closing in on answers.
For a new study published in the May 16 issue of the journal PLoS One, scientists at UCLA used brain-mapping data from computed tomography (CT) and magnetic resonance imaging (MRI) scans to determine the specific damage inflicted on the neurological "pathways" in Gage's brain.
"What we found was a significant loss of white matter connecting the left frontal regions and the rest of the brain," study co-author Jack Van Horn, an assistant professor of neurology at the university, said in a written statement. "We suggest that the disruption of the brain's 'network' considerably compromised it. This may have had an even greater impact on Mr. Gage than the damage to the cortex alone in terms of his purported personality change."
Only about 4 percent of Gage's cerebral cortex was directly affected by the rod, the study showed. But more than 10 percent of the white matter was damaged. The white matter is the fatty tissue within the brain that coordinates communication between its different regions.
In addition to helping explain Gage's deterioration, the study showcases the power of brain mapping--a technology that neurologists believe will lead eventually to an understanding of the links between the brain's "wiring" and specific mental disorders, according to the statement.
"The extensive loss of white matter connectivity, affecting both hemispheres, plus the direct damage by the rod, which was limited to the left cerebral hemisphere, is not unlike modern patients who have suffered a traumatic brain injury," Van Horn said in the statement, adding that the loss of connectivity was analogous to that seen in Alzheimer's disease and other neurodegenerative diseases.
What happened to Gage after the accident? He worked at a stable in New Hampshire and then as a stagecoach driver in Chile before moving to San Francisco. He died there after a series of seizures 12 years after the accident.
But not all of Gage is gone. His 189-year-old skull is on display at Warren Anatomical Museum in Boston. The tamping rod? It's there too.
In the late 18th century, King Gustavus III of Sweden was rumored to have carried out a strange experiment to determine the harmful health effects of coffee. Two identical twins who had been condemned to death had their sentences commuted to life in prison on the condition that one would drink three pots of coffee per day, and the other three pots of tea, for the rest of their lives. The only problem was that the doctors assigned to monitor the cases died before either of the patients did, their observations lost--as the story goes, the tea drinker died first, and there's no record of the coffee-drinker's death. The experiment proved nothing, suffering from a lack of rigor (to say the least). Source: Uppsala University, "Coffee - rat poison or miracle medicine?"
In June 1966, the U.S. Army's Special Operations Division secretly dispersed harmless bacteria in the New York Subway system to model the effects of an outbreak of more harmful germs. According to Army reports, "Test results show that a large portion of the working population of New York City would be exposed to disease if one or more pathogenic agents were disseminated covertly in several subway lines at a period of peak traffic." Source: Deadly Cultures: Biological Warfare Since 1945. Wheelis, Rózsa, and Dando. Harvard University Press, 2006.
Operation Big Itch, 1954, was an attempt to discover the potential of weaponized fleas. The operation, part of the Cold War-era United States biological weapons program, took place at Dugway Proving Ground in Utah. According to "Using the flea as weapon," an article in the Army Chemical Review, "In the United States, the plague flea concept was competing against the use of mosquitoes, flies, ticks, and lice. Of these concepts, the United States put most of its energies behind weaponizing yellow fever in combination with the Aedes aegypti mosquito."
U.S. Army Surgeon William Beaumont (above) found an extraordinary patient in Alexis St. Martin, a Canadian trapper who was injured in a hunting accident and left with a hole in his belly that led directly into his stomach. Beaumont attached a string to various foods, including oysters and rare roast beef, and introduced them into the wound to observe the rates of digestion. Despite the unorthodox techniques, this research would later lead to the discovery of the importance of stomach acid in digestion, earning Beaumont the epithet "father of gastric physiology." Source: Experiments and observations on the gastric juice, and the physiology of digestion. Beaumont, Martin and Combe. Maclachlan & Stewart, 1838
In 1945, Sweden's new National Dental Service commissioned research, now known as the Vipeholm experiments, in which researchers gave subjects large amounts of sticky sugary candy in order to study the development of cavities. This might not have been so controversial, except that the subjects couldn't give consent to their participation: "The use of mentally handicapped subjects was criticized in the Swedish press and all studies on mentally handicapped individuals were stopped in 1954," according to Topics In Dental Biochemistry by Mark Levine (Springer, 2010).