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One of the most pervasive “pseudo facts” about the human brain is the assertion that we only use about ten percent of our brain capacity. It is likely that this myth arose from research during the 1930s when scientists were uncertain regarding the functions of large areas of the cortex. In recent years, thanks to increasingly sophisticated brain scan technology, researchers have been able to “map” the functions of different areas of the brain. While there appears to be some redundancy, there are high degrees of specialization in some areas, especially those governing speech and abstract thinking.
For its small size, with a weight of about three pounds, the human brain is a wonderful instrument and harbors many mysteries yet to be solved. The neocortex, the outer layer of the brain, by which we perform higher thinking, consists of a thin sheet of cells about 2.5 millimeters in thickness. In addition to containing our “thinking tissue,” the neocortex is also made up of cortical blood vessels and supportive cells for the neuronal (nerve) matrix. If the neocortex is damaged in humans and higher mammals, the result is a condition known as decorticate rigidity in which the thinking processes are shut down.
From the perspective of human evolution, the neocortex is built upon the older brain in the cerebellum and brainstem which perform the autonomic functions, such as posture, heart rate, blood pressure, and the onset of sleep. The brainstem is a primitive area of the brain that merges the lower brain into the spinal cord. Without the neocortex, consciousness as we understand it would not exist. However, the neocortex can’t even stay awake to perform the simplest of tasks without constant stimulation from the brainstem.
Although the neocortex is the crowning achievement of human evolution, it does contain large cavities without any brain cells, as well as considerable amounts of cerebrospinal fluid, white matter, blood vessels, blood, and “non-thinking cells.” And, while scientists caution against suggesting that these areas constitute the mythical unused 90 percent of the brain, they do admit that some individuals have been able to function with only a tiny fraction of the brain—or no brain at all.
On July 20, 2007, neurologists at the University of Marseille revealed the remarkable case of the 44-year-old French tax official who had been managing just fine with a fluid-filled cavity taking up most of the space where his brain should have been. Writing in the medical journal Lancet, doctors described how the civil servant had gone to the hospital in 2003 complaining of a slight weakness in his left leg. When the doctors scanned his brain to see if the problem lay there, they found mostly a black hole.
The patient told the attending physicians that as a six-month-old baby he had suffered from hydrocephalus (commonly known as “water on the brain”) and that a shunt had been inserted to drain away the fluid. Dr. Lionel Fuilet ordered a tomography scan (CT) and an MRI (magnetic resonance imaging scan) and discovered that the lateral ventricles, chambers that hold and cushion the brain, were extremely enlarged. In the normal brain, these ventricles are very small.
Upon close examination, Dr. Fuilet and his team found that a massive cavity had built up in the man’s skull and that it had filled with fluid and a thin sheet of functioning brain tissue, which was pushed back against the inner walls of his cranium.
Tests by the medical team revealed that the tax official was neither physically nor mentally disabled by his strange condition and that it had not hindered his socialization. The man was married with two children and carried out his duties at the tax office without difficulty. IQ tests indicated the man’s score to be 75 (average IQ is around 100).
Der Spiegel quoted Florian Heinen, a brain development expert at the Dr. von Hauner Children’s Hospital at Munich University, who explained that while the French tax official’s case was extremely rare, his was one of a number of cases in which individuals had functioned quite well with a very small amount of brain matter. The most striking observation Heinen made was that “these few brain cells can achieve just as much as the millions more cells that other people have.”....Read the rest of this article exclusively in the January 2008 issue of FATE!