May 15, 2014

The Life and Afterlife of a Classic Case Study

Back in the 1990s, when echolyn had briefly (thankfully) broken up, keyboard player Chris Buzby formed a band that made a couple of albums chock full of fusion-tinted complex prog.*  The band was called finneus gauge, which, it became clear, was a transliteration of the name of one of the most famous accidental test cases in neurological history.

Phineas Gage was an explosives guy in antebellum New England.  The tools of his trade were gunpowder and a 3.5 foot steel rod he used to tamp it (and other materials) into a hole in preparation for blasting.  The rod weighed more than 13 pounds and tapered to a point at one end.

He and his crew had been hired to blast some rock in Vermont in 1848 when, on on fall afternoon, this happened:
Gage’s crew members were loading some busted rock onto a cart, and they apparently distracted him. Accounts differ about what happened after Gage turned his head. One says Gage tried to tamp the gunpowder down with his head still turned, and scraped his iron against the side of the hole, creating a spark. Another says Gage’s assistant (perhaps also distracted) failed to pour the sand in, and when Gage turned back, he smashed the rod down hard, thinking he was packing inert material. Regardless, a spark shot out somewhere in the dark cavity, igniting the gunpowder, and the tamping iron rocketed upward.
The iron entered Gage’s head point-first, striking below the left cheekbone. It destroyed an upper molar, passed behind his left eye, and tore into the underbelly of his brain’s left frontal lobe. It then plowed through the top of his skull, exiting near the midline, just behind where his hairline started. After parabola-ing upward—one report claimed it whistled as it flew—the rod landed 25 yards away and stuck upright in the dirt, mumblety-peg-style. Witnesses described it as streaked with red and greasy to the touch, from fatty brain tissue.
What makes Gage's story so compelling is that not only did he survive the injury, he never even lost consciousness.  But, surely, the 13-pound hunk of metal that flew through his skull and brain must have had some impact on him, right?

As this article by Sam Kean at Slate points out, it's not altogether certain.  Over the years, the perception of Gage's life after his initial recovery has changed.  If Paul Simon's right that "every generation throws a hero up the pop charts," then, similarly, every generation interprets Gage for their own purposes.

Part of the problem is that there is precious little information about Gage's life, at least reliable information.  As the piece points out, the first news article about Gage contained an minor error (about the size of the rod), which seems to be a harbinger of things to come.

For instance, there were only two medical reports made about Gage, the second of which was by a doc at Harvard Medical School, but it didn't contain a lot about his actual behavior.  At the time, doctors thought that the part of the brain that got blasted by the rod wasn't all that important:
Frustratingly, Harlow limited his discussion of Gage’s mental status to a few hundred words, but he does make it clear that Gage changed—somehow. Although resolute before the accident, Harlow says Gage was now capricious, and no sooner made a plan than dropped it for another scheme. Although deferential to people’s wishes before, Gage now chafed at any restraint on his desires. Although a 'smart, shrewd businessman' before, Gage now lacked money sense. And although courteous and reverent before, Gage was now 'fitful [and] irreverent, indulging at times in the grossest profanity.' Harlow summed up Gage’s personality changes by saying, 'the equilibrium ... between his intellectual faculties and his animal propensities seems to have been destroyed.' More pithily, friends said that Gage 'was no longer Gage.'
Gage lost his job and wound up as a travelling curiosity.  Until, it seems, he went to Chile, found work as a coach driver, and generally lived an ordinary life.  It's unclear from the record whether he underwent a sudden shift brought about by the accident or if he, perhaps slowly, returned to normal.  Part of the problem is trying to make too much out of a sparse factual record:
People butcher history all the time, of course, for various reasons. But something distinct seems to have happened with Gage. Macmillan calls it 'scientific license.' 'When you look at the stories told about Phineas,' he says, 'you get the impression that [scientists] are indulging in something like poetic license—to make the story more vivid, to make it fit in with their preconceptions.' Science historian Douglas Allchin has noted the power of preconceptions as well: 'While the stories [in science] are all about history—events that happened,' Allchin writes, 'they sometimes drift into stories of what ‘should’ have happened.'
With Gage, what scientists think 'should' have happened is colored by their knowledge of modern patients. Prefrontal lobe damage is associated with a subsequent slightly higher rate of criminal and antisocial behavior. Even if people don’t sink that low, many do change in unnerving ways: They urinate in public now, blow stop signs, mock people’s deformities to their faces, or abandon a baby to watch television. It’s probably inevitable, Macmillan says, that such powerful anecdotes influence how scientists view Gage in retrospect: 'They do see a patient and say, 'Ah, he’s like what Phineas Gage was supposed to be like.' ' To be clear, Harlow never reports anything criminal or blatantly unhinged about Gage’s conduct. But if you’re an expert on brain damage, scientific license might tempt you to read between the lines and extrapolate from 'gross profanity' and 'animal passions' to seedier behavior.
If repeated often enough, such stories acquire an air of truthiness.
The whole article is fascinating.  Kean even traces the history of the rod itself, which now resides in a display case along with Gage's skull!  Go check it out.

* Seriously, they're worth tracking down, particularly the debut, more once more.  And I don't just say that because the band used a blurb from my review in its advertising.

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