Why Brain Scientists Are Still Obsessed With The Curious Case Of Phineas Gage ?

JON HAMILTON

Image result for images of the brain

It took an explosion and 13 pounds of iron to usher in the modern era of neuroscience.

In 1848, a 25-year-old railroad worker named Phineas Gage was blowing up rocks to clear the way for a new rail line in Cavendish, Vt. He would drill a hole, place an explosive charge, then pack in sand using a 13-pound metal bar known as a tamping iron.

But in this instance, the metal bar created a spark that touched off the charge. 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, an associate professor of neurology at the Keck School of Medicine at the University of Southern California.

Gage didn’t die. But the tamping iron destroyed much of his brain’s left frontal lobe, and Gage’s once even-tempered personality changed dramatically.

“He is fitful, irreverent, indulging at times in the grossest profanity, which was not previously his custom,” wrote John Martyn Harlow, the physician who treated Gage after the accident.

This sudden personality transformation is why Gage shows up in so many medical textbooks, says Malcolm Macmillan, an honorary professor at the Melbourne School of Psychological Sciences and the author of An Odd Kind of Fame: Stories of Phineas Gage.

“He was the first case where you could say fairly definitely that injury to the brain produced some kind of change in personality,” Macmillan says.

And that was a big deal in the mid-1800s, when the brain’s purpose and inner workings were largely a mystery. At the time, phrenologists were still assessing people’s personalities by measuring bumps on their skull.

Gage’s famous case would help establish brain science as a field, says Allan Ropper, a neurologist at Harvard Medical School and Brigham and Women’s Hospital.

One Account Of Gage’s Personality Shift

Dr. John Harlow, who treated Gage following the accident, noted his personality change in an 1851 edition of the American Phrenological Journal and Repository of Science.

“If you talk about hard core neurology and the relationship between structural damage to the brain and particular changes in behavior, this is ground zero,” Ropper says. It was an ideal case because “it’s one region [of the brain], it’s really obvious, and the changes in personality were stunning.”

So, perhaps it’s not surprising that every generation of brain scientists seems compelled to revisit Gage’s case.

For example:

  • In the 1940s, a famous neurologist named Stanley Cobb diagrammed the skull in an effort to determine the exact path of the tamping iron.
  • In the 1980s, scientists repeated the exercise using CT scans.
  • In the 1990s, researchers applied 3-D computer modeling to the problem.

And, in 2012, Van Horn led a team that combined CT scans of Gage’s skull with MRI scans of typical brains to show how the wiring of Gage’s brain could have been affected.

“Neuroscientists like to always go back and say, ‘we’re relating our work in the present day to these older famous cases which really defined the field,’ ” Van Horn says.

And it’s not just researchers who keep coming back to Gage. Medical and psychology students still learn his story. And neurosurgeons and neurologists still sometimes reference Gage when assessing certain patients, Van Horn says.

“Every six months or so you’ll see something like that, where somebody has been shot in the head with an arrow, or falls off a ladder and lands on a piece of rebar,” Van Horn says. “So you do have these modern kind of Phineas Gage-like cases.”

Two renderings of Gage’s skull show the likely path of the iron rod and the nerve fibers that were probably damaged as it passed through.

Van Horn JD, Irimia A, Torgerson CM, Chambers MC, Kikinis R, et al./Wikimedia

There is something about Gage that most people don’t know, Macmillan says. “That personality change, which undoubtedly occurred, did not last much longer than about two to three years.”

Gage went on to work as a long-distance stagecoach driver in Chile, a job that required considerable planning skills and focus, Macmillan says.

This chapter of Gage’s life offers a powerful message for present day patients, he says. “Even in cases of massive brain damage and massive incapacity, rehabilitation is always possible.”

Gage lived for a dozen years after his accident. But ultimately, the brain damage he’d sustained probably led to his death.

He died on May 21, 1860, of an epileptic seizure that was almost certainly related to his brain injury.

Gage’s skull, and the tamping iron that passed through it, are on display at the Warren Anatomical Museum in Boston, Mass.

Mouse Brain Visualized in Stunning 3D Detail

One small step for man, one giant leap for mousekind.

Scientists have painstakingly mapped the connections in a tiny segment of the mouse’s brain. The stunningly intricate picture provides an unprecedented level of detail of an organ smaller than a pebble and lighter than the average cotton ball.

“At the end of the day, we want to understand the human brain. Understanding the mouse brain is an important step toward that goal,” Lydia Ng, senior director of technology at the nonprofit Allen Institute for Brain Science in Seattle, told Live Science in an email.

The resulting 3D structure, called the Mouse Common Coordinate Framework, is the equivalent of leveling up from simple paper maps to a Google Maps or GPS for the mouse brain, Ng said.

“Maps of the brain have always been created in two dimensions, but even a stack of flat maps sitting on top of each other does not necessarily align with the complex three-dimensional nature of the brain,” neuroscientist Christof Koch, the president and chief scientific officer of the Allen Institute for Brain Science, said in a statement. [See Images of the Mouse Brain Up Close]

Detailed picture

The new map, however, doesn’t just track the firing between different brain cells; it also allows researchers to visualize how different genes are expressed in teensy portions of the brain as well as the physical connections between anatomical structures in the brain.

To create this detailed map, researchers carefully measured and examined 1,675 mouse brains and then created a 3D image of an “average mouse brain.” From there, the scientists used fluorescently labeled brain cells from the mouse brain as clues to help draw the boundaries between different brain regions. Ultra-high-resolution images of individual brain cells were then translated into digital images.

The ultimate goal for this project, as well as for the the National Institutes of Health’s larger BRAIN Initiative, which helped fund the current project, is to create a detailed map of all the connections in the human brain. Though the mouse brain is an important first step, there are many more to go. The human brain weighs about 3.3 pounds (1.5 kilograms), whereas the mouse brain weighs just 0.02 ounces (0.5 grams) — or about the weight of a paper clip. What’s more, the mouse brain contains just 70 million neurons, whereas the human brain contains a whopping 86 billion neurons, according to a study published in 2012 in the journal Nature.

Any researcher interested in using the framework or looking at the data can do so at brain-map.org, Ng said.

Original article on Live Science.