http://esciencenews.com/articles/2012/05/17/ucla.researchers.map.damaged.connections.phineas.gages.brain
Poor Phineas Gage. In 1848, the supervisor for the Rutland and
Burlington Railroad in Vermont was using a 13-pound, 3-foot-7-inch rod
to pack blasting powder into a rock when he triggered an explosion that
drove the rod through his left cheek and out of the top of his head. As
reported at the time, the rod was later found, "smeared with blood and
brains." Miraculously, Gage lived, becoming the most famous case in the
history of neuroscience -- not only because he survived a horrific
accident that led to the destruction of much of his left frontal lobe
but also because of the injury's reported effects on his personality and
behavior, which were said to be profound. Gage went from being an
affable 25-year-old to one that was fitful, irreverent and profane. His
friends and acquaintances said he was "no longer Gage."
Reporting in the May 16 issue of the journal PLoS ONE, Jack Van
Horn, a UCLA assistant professor of neurology, and colleagues note that
while approximately 4 percent of the cerebral cortex was intersected by
the rod's passage, more than 10 percent of Gage's total white matter
was damaged. The passage of the tamping iron caused widespread damage to
the white matter connections throughout Gage's brain, which likely was a
major contributor to the behavioral changes he experienced.
"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," he said. "And it is analogous to
certain forms of degenerative diseases, such as Alzheimer's disease or
frontal temporal dementia, in which neural pathways in the frontal lobes
are degraded, which is known to result in profound behavioral changes."
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