French Man Leads A Normal Life Despite Missing 90 Percent Of His Brain

Nine years ago, a middle-aged French man entered a clinic to have an aching leg checked out. What doctors discovered was absolutely baffling; the 44-year old father of two was missing almost all of his brain.

According to The Lancet, the medical mystery unfolded when the unidentified civil service worker sought help for leg pain with which he’d been suffering for at least two weeks. His childhood medical history was unremarkable, aside from a procedure to install a ventriculoatrial shunt at age six months and a revision of the shunt at age 14.

Mayo Clinic explains that a ventriculoatrial shunt is a flexible tube with a one-way valve that is surgically inserted to drain excess fluid from the brain and channel it into a chamber of the heart. Implantation of such a device is one of the most common treatments for a condition known as hydrocephalus.

Colloquially called “water on the brain” or “water head,” hydrocephalus occurs when an overabundance of cerebrospinal puts pressure on the brain. The condition also causes an abnormal increase of the size of one or more the brain’s four ventricles, or cavities, inside the brain. Hydrocephalus generally presents in infancy, but can show up at later stages in life. According to The Lancet, the patient was shunted when he was six months old due to “postnatal hydrocephalus of unknown cause.” At age 14, the patient experienced loss of strength and coordination in his left leg. His shunt was adjusted, and he went on with his life.

Because of his history of infantile hydrocephalus and similar troubling leg issues as a child, French physicians performed a number of neuropsychological tests and brain scans that revealed the man to have an IQ of 75 with a verbal IQ of 84. His intelligence was indeed lower than average, but that did not interfere with the patient’s ability to lead a rich, full life that included a marriage, a couple of kids and full-time employment at a job he enjoyed. So, when the doctors in France took CT and MRI scans of his brain, they were undoubtedly astonished to find that the man with the sore leg was missing around 90 percent of his brain.

The Lancet notes that the brain scans revealed that three of the man’s brain ventricles were filled with nothing but fluid, and that his brainstem and cerebellum were sharing limited cranial space with a sizeable cyst. Essentially, his brain consisted of little more than a thin, soft shell of cortical neurons filled with fluid.

That the man was able to lead a normal life with most of his brain gone flies in the face of what scientists think they know about human consciousness. The generally accepted theory among neuroscientists is that conscious awareness is dependent on a part of the brain called the thalamus. According to IFLScience, this theory is the result of research that proves damage to the thalamus can trigger a coma. Additionally, researchers have been able to “switch off” an epileptic seizure and induce deep sleep by stimulating this part of the brain. The thalamus helps to manage voluntary movement and physical coordination. Additionally, the thalamus is directly involved in the sensory system, communicating every sense except smell.

Scientists are still baffled by the fact that an otherwise healthy Frenchman managed to live a completely normal for years and year with little more than the skin of his brain. The fascinating revelation certainly begs the question of whether human consciousness “lives” in a specific physical part of the anatomy or if neurons adapt to explore every possible way to communicate with one another.

[Photo by Vetre/Fotolia/AP Images]