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If you are not familiar with the case, you can read more on Wiki.
TL;DR Phineas Gage had a big iron rod travel through his brain in an explosion in 1848. He survived but suffered significant personality changes. This became the topic of great debate about the brain and its functions.
Apparently he recovered a lot later in life but then started having seizures and died. A really curious case overall.
Really weird. Especially given the state of medical science at the time. I'm surprised he did not die of an infection.