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IN the 1860s, the French physician Paul Broca treated two patients who had lost the ability to speak after suffering strokes. When they died, he examined their brains, and noticed that both had damage to the same region of the left frontal lobe. About a decade later, neuropsychiatrist Carl Wernicke described a stroke patient who was unable to understand written words or what was said to him, and later found in this patient's brain a lesion towards the back of the left temporal lobe.
Thus was established the classical neurological model, in which language is localized to two specific areas…