Did an iron rod through his head really turn Phineas Gage into a different man?

In 1848 a railway foreman named Phineas Gage was at work when an accident drove his tamping iron, a long iron rod, right through his head. It passed behind his left eye and out the top of his skull, destroying much of his left frontal lobe. He survived, and for a time at least, friends saw him as "no longer Gage". That line made him famous in brain science: he may have been the first case to suggest that damage to one part of the brain could change a person's character.

The accident really was astonishing. The rod was 1.1 metres long and weighed about 6 kilograms. Gage was thrown on his back and convulsed for a moment, yet he spoke within minutes, walked with little help and sat upright in an ox-cart. When a doctor arrived, Gage greeted him with "Doctor, here is business enough for you."

The famous second half of the story is much shakier. The doctor who treated him, John Harlow, noted that Gage's memory and intelligence seemed unimpaired, and he waited until 1868, after Gage was dead, to publish his description of the personality change. The mental changes reported after Gage's death were far more dramatic than anything written while he was alive, and later accounts piled on more. Gage later worked as a long-distance stagecoach driver in Chile, and a physician who knew him there found no impairment whatever of his mental faculties. So Gage is two stories: a real injury that hinted the brain shapes personality, and a legend that grew in the telling.