What did the iron bar through Phineas Gage's frontal lobe change, and how much of the story is true? · Grey Matter

In 1848 a tamping iron about a metre long shot through the left cheek and out of the top of the head of a railway foreman, destroying much of the left frontal lobe, mainly its orbital and medial prefrontal parts and the white matter beneath.

What did the iron bar through Phineas Gage's frontal lobe change, and how much of the story is true?

In 1848 a tamping iron about a metre long shot through the left cheek and out of the top of the head of a railway foreman, destroying much of the left frontal lobe, mainly its orbital and medial prefrontal parts and the white matter beneath. He survived, and his doctor reported that the efficient, well-liked man had become impulsive and profane. The historian Malcolm Macmillan later showed that many dramatic details were added by authors who never met him, and that Gage seems to have recovered substantially, later working for years as a stagecoach driver in Chile. The case still stands as early evidence that frontal damage can change judgement and social behaviour while leaving movement, speech and memory intact.