Broca’s later autopsy of the man found damage to a portion of the brain that the doctor tied to the capacity to speak. (Nina Dronkers/Nina Dronkers)

The identity of a mysterious patient who helped scientists pinpoint the brain region responsible for language has been discovered, researchers report.

The finding, detailed in the January issue of the Journal of the History of the Neurosciences, identifies the patient as Louis Leborgne, a French craftsman who battled epilepsy his entire life.

In 1840, a wordless patient was admitted to the Bicetre Hospital outside Paris for aphasia, or an inability to speak. He was essentially just kept there, slowly deteriorating. It wasn’t until 1861 that the man, who was known only as “Monsieur Leborgne” and who was nicknamed “Tan” for the only word he could say, came to physician Paul Broca’s ward at the hospital.

Leborgne died shortly after the meeting, and Broca performed his autopsy, during which Broca found a lesion in a region of the brain tucked back and up behind the eyes.

After doing a detailed examination, Broca concluded that Tan’s aphasia was caused by damage to this region and that the particular brain region controlled speech. That part of the brain was later renamed Broca’s area.

At a time when scientists were debating whether different areas of the brain performed separate functions, physician Paul Broca examined a patient who could say only one word. (Welcome Library/Welcome Library)

At the time, scientists were debating whether different areas of the brain performed separate functions or whether it was an undifferentiated lump that did one task, like the liver, said Marjorie Lorch, a neurolinguist in London who was not involved in the study.

“Tan was the first patient whose case proved that damage to a specific part of the brain causes specific speech disorders,” said the author of the new study, Cezary Domanski, a medical historian in Poland.

Life reconstructed

Yet Tan’s exact identity remained shrouded in mystery. Most historians believed he was a poor, illiterate laborer, while others said that he had gone mad from syphilis and that madness could explain his inability to speak. To discover just who he was, Domanski began to trace the man’s history.

“It was a challenge. For 150 years, no one could even determine the name of the man — the same man whose brain is exhibited in a museum and shown in many books,” Domanski wrote in an e-mail.

But looking through the old medical records, he uncovered a death certificate for a Louis Victor Leborgne, who had been born in 1809 in Moret, France.

Domanski then used archival records to discover that Louis Leborgne was one of seven children, that his father was a teacher and that his siblings were educated. He moved to Paris as a child.

Leborgne had apparently suffered epilepsy from childhood. Despite his seizures, he grew up to be a craftsman and worked as a church keeper until he was 30 years old, when he lost the ability to speak and was taken to the hospital. Epilepsy probably caused the damage that took away Leborgne’s power of speech.

In the hospital, his condition worsened; he eventually became paralyzed and bedridden, and he underwent surgery for gangrene. He was dying when Broca first encountered him.

The discovery gives a very human identity to one of medicine’s most famous cases, Lorch said.

“Language, because it was viewed at that time in Europe as a God-given ability in humans, it was considered part of the soul and therefore not material,” Lorch said. “This case was the case that really established the whole area of research on functional organization of the brain.”

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