On April 18, 1861, a doctor in Paris, Dr. Paul Broca, inadvertently identified a brain region that is crucial to speech processing. The damage to this general region of the brain was associated with aphasia, a form of cognitive function. The patient, Louis Victor Leborgne, was nicknamed "Tan" by doctors at Bicêtre Hospital and lost his ability to speak at age 30 and spent 21 years in the psychiatric ward of the hospital. After an autopsy, Broca noted a pocket of clear fluid in the perisylvian region of brain's left hemisphere, which surrounded a deep groove called the lateral sulcus. Since then, he identified the precise area and later narrowed it down to the left frontal lobe.