A railroad worker who survived an astonishing accident more than 170 years ago has gone on to become one of the more fascinating medical stories of all time, inspiring imaging research to this very day. Big Think examined the incident in detail, explaining what makes this worker “a blank canvas for generations of science.”

Phineas Gage was working on a railroad in 1848 when an explosion caused a piece of iron to slam through his jaw and out the top of his skull. He somehow survived the incident, but it supposedly left him a changed man—reports from the time indicated it altered his behavior in extreme ways, though Big Think notes how this may not necessarily be the case.

Still, Gage’s survival, and the impact it may or may not have had on him, continues to interest scientists. Researchers have used CT scans to try and trace the path the iron took through his skull, for instance, while a different group used both CT scans and MRI scans to look into the incident.

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