Phineas Gage

Phineas P. Gage (1823 – May 21, 1860) was a railroad construction foreman who suffered a traumatic brain injury when a tamping iron accidentally passed through his skull, damaging the frontal lobes of his brain. This injury is supposed to have negatively affected his emotional, social and personal traits—leaving him in a temperamental and unsociable state, so much so that his friends said he was "no longer Gage".

At the time of its report to the scientific community, Gage's condition led to changes in the scientific perception of the function and compartmentalisation of the brain with regards to emotion and personality. Gage's case is cited as among the first evidence suggesting that damage to the frontal lobes could alter aspects of personality and affect socially appropriate interaction. Before this time the frontal lobes were largely thought to have little role in behavior.