__Science tells us that particular areas of the brain carry out specific functions, so how do people with damaged or underdeveloped brains still function normally?

In 1996 in the US, a young boy, here referred to as James, was about to undergo a serious operation.  James was only eight years old and suffered from a condition known as Sturge-Weber syndrome, which had caused the formation of abnormal blood vessels in the left hemisphere of his brain.  As a result he was afflicted by regular epileptic fits and had a very low mental age; the only word in James's vocabulary was "Mamma."

In an attempt to to rectify the problem, doctors felt forced to take drastic steps.  They decided to remove the entire left side of his brain.   The medical team knew that, since the left side of the brain controls the right side of the body, the operation to save James's life would also leave him partially paralysed.  What they didn't expect, however, were the developments in James's condition which occurred soon after the surgery.  Within weeks, James began to talk and, two years later, was close to reaching a normal mental age.  Amazingly, the operation to remove an entire hemisphere of his brain appears to have cured him of his learning difficulties.

Such remarkable examples of adaptability are far more common than we might think.  In conflict with established medical thinking, there are literally hundreds of cases where people have either been born with an underdeveloped brain, or have had large areas of their brain damaged in an accident, but are still able to function normally.

Such anomalies were partly explained when it was discovered that we have the ability to relocate particular brain functions to other areas of the brain.  Exactly how this works is still beyond modern science, and so the ability lies in limbo between accepted medical fact and that which is still regarded as nonsense.  However, it may be that this discovery is only the tip of the iceberg, for there are people whose very existence seems to indicate that our brains are nowhere near as vital to our survival as we might think.

In countries across the world, there are hundreds of cases of a condition called hydrocephalus (often known colloquially as "water on the brain"), where cavities form in the brain that can be so large that they account for 95% of the brain's mass.  This leaves only a fluid-filled bubble of the outermost cerebral tissue which, in extreme cases, has been found to be less than one millimetre thick.  (Ordinarily, the walls of the cerebrum are 45mm thick.)  The condition is so serious that, if it is recognised before birth, a decision is often taken to terminate the pregnancy because only a small proportion of sufferers survive.

In those born with this condition, the body's production of the cerebrospinal fluid (CSF) which fills the cavities in the brain is working at a rate well above the norm.  This usually leads to a swelling of the cranium; one six-year-old boy had a skull with a circumference 72cm greater than that of the average adult.  Modern techniques, however, allowed doctors to drain the fluid until normal pressure was restored and the boy survived.

Despite the seriousness of this condition, in some people it appears to have little or no effect on their intellectual abilities.  Indeed, to the surprise of the medical establishment, in a study of 253 hydrocephalus sufferers carried out by the University of Sheffield, Professor John Lorber discovered that there is no relation between volume of brain tissue and IQ.

Surprising Results
Of the 253 subjects in the study, 9 were found to have approximately only 5% of the normal amount of brain tissue.  Despite this, 4 had IQ's of above 100, the national average, and another 2 had IQ's of above 126, while one of the subjects proved to be as intelligent as those studying him, he had a first-class degree in maths.

One possible explanation for such achievements as this is the neopallium, which forms the very outermost layer of the brain.  Since the brains are larger with hydrocephalus sufferers, they have larger neopalliums while the brain mass is diminished in bulk.  The neopallium is the site for some of the most important mental functions, such as the power of reasoning.

Cases such as these have been cropping up regularly to test the stability of modern medicine, yet are largely disregarded.  They undermine established beliefs about the relationship between the human brain and the site of consciousness and so are largely ignored by mainstream medical science.  When asked about the impact of his research into hydrocephalus sufferers, Professor Lorber said it had "suffered a fate like much of the literature of phenomenological science: it was ignored."

While science chooses to blinker itself, these medical anomalies continue to walk the streets, their fluid-filled craniums not preventing them from leading normal lives and taking degrees.

Brainless Boy
One related case that has received more exposure than most is that of Andrew Vandal, who was born on 12 July 1984.  In the early stages of his development in the womb a cyst appeared on the stem of his brain.  Known as an 'atelencephic aprosencephaly', this destructive event left the boy with a cranium containing nothing but fluid.  In some cases, it can even leave victims with no detectable brain at all - a condition known as anencephaly or 'brainlessness'. 

Cases like Andrew's are again usually terminated before birth, but in this instance the subject was born and then put up for adoption.  He was adopted by a pædiatric nurse, Kaye Vandal, from Wallingford, Connecticut, US, who, when last asked about Andrew's welfare, stated that she remained devoted to "giving him the best quality life for however long he lives". 

At the same time Kaye stated that, against doctors' predictions, Andrew was able to laugh, giggle and smile and has a "glowing, outgoing, bubbly personality".  Kaye also stated that her young charge was able to respond to stimulus and was maturing mentally; both of which doctors believed to be impossible, considering his complete absence of brain matter.

Andrew was, however, unable to speak, and was cortically blind; that is, he could see images, but was unable to interpret them.  Andrew was also incapable of walking, but did manage to drag himself along on his back.  Cases such as Andrew's provide real-life testimony to our astonishing adaptability as biological organisms.

Source: mysteries.pwp.blueyonder.co.uk

_ Is the Brain Really Necessary?

This was the question asked by British neurologist John Lorber when he addressed a conference of pædiatricians in 1980.  Such a frivolous sounding question was sparked by case studies Lorber had been involved in since the mid-60s.  The case studies involved victims of an ailment known as hydrocephalus, more commonly known as "water on the brain".  The condition results from an abnormal build up of cerebrospinal fluid and can cause severe retardation and death if not treated.

Two young children with hydrocephalus referred to Lorber presented with normal mental development for their age.  In both children, there was no evidence of a cerebral cortex.  One of the children died at age 3 months, the second at 12 months.  He was still following a normal development profile with the exception of the apparent lack of cerebral tissue shown by repeated medical testing.  An account of the children was published in Developmental Medicine and Child Neurology.

Later, a colleague at Sheffield University became aware of a young man with a larger than normal head.  He was referred to Lorber even though it had not caused him any difficulty.  Although the boy had an IQ of 126 and had a first class honours degree in mathematics, he had "virtually no brain".  A non-invasive measurement of radio density known as a CAT scan showed the boy's skull was lined with a thin layer of brain cells to a millimeter in thickness.  The rest of his skull was filled with cerebrospinal fluid.  The young man continues a normal life with the exception of his knowledge that he has no brain.

Although anecdotal accounts may be found in medical literature, Lorber is the first to provide a systematic study of such cases.  He has documented over 600 scans of people with hydrocephalus and has broken them into four groups:

• those with nearly normal brains
• those with 50-70% of the cranium filled with cerebrospinal fluid
• those with 70-90% of the cranium filled with cerebrospinal fluid
• and the most severe group with 95% of the cranial cavity filled with cerebrospinal fluid.

Of the last group, which comprised less than 10% of the study, half were profoundly retarded.  The remaining half had IQs greater than 100.  Skeptics have claimed that it was an error of interpretation of the scans themselves.  Lorber himself admits that reading a CAT scan can be tricky.  He also has said that he would not make such a claim without evidence.  In answer to attacks that he has not precisely quantified the amount of brain tissue missing, he added, "I can't say whether the mathematics student has a brain weighing 50 grams or 150 grams, but it is clear that it is nowhere near the normal 1.5 kilograms."

Many neurologists feel that this is a tribute to the brain's redundancy and its ability to reassign functions.  Others, however, are not so sure.  Patrick Wall, professor of anatomy at University College, London states "To talk of redundancy is a cop-out to get around something you don't understand."

Norman Geschwind, a neurologist at Boston's Beth Israel Hospital agrees: "Certainly the brain has a remarkable capacity for reassigning functions following trauma, but you can usually pick up some kind of deficit with the right tests, even after apparently full recovery."

References: 
Anthony Smith The Mind New York Viking Press, 1984, page 230
Roger Lewin "Is Your Brain Really Necessary?"Science 210 December 1980, page 1232
Source: web.syr.edu 30 October 1993

_Tiny Brain No Obstacle to French Civil Servant

_Washington - A man with an unusually tiny brain managed to live an entirely normal life despite his condition, caused by a fluid buildup in his skull, French researchers reported.  Scans of the 44-year-old man's brain showed that a huge fluid-filled chamber called a ventricle took up most of the room in his skull, leaving little more than a thin sheet of actual brain tissue.  "He was a married father of 2 children, and worked as a civil servant," Dr Lionel Feuillet and colleagues at the Universite de la Mediterranee in Marseille wrote in a letter to the The Lancet medical journal.

The man went to a hospital after he had mild weakness in his left leg.  When Feuillet's staff took his medical history, they learned he had had a shunt inserted into his head to drain away hydrocephalus - water on the brain - as an infant.  The shunt was removed when he was 14.  So the researchers did a computed tomography (CT) scan and another type of scan called magnetic resonance imaging (MRI).  They were astonished to see "massive enlargement" of the lateral ventricles - usually tiny chambers that hold the cerebrospinal fluid that cushions the brain.

Intelligence tests showed the man had an IQ of 75, below the average score of 100 but not considered mentally retarded or disabled, either.

"What I find amazing to this day is how the brain can deal with something which you think should not be compatible with life," commented Dr Max Muenke, a paediatric brain defect specialist at the National Human Genome Research Institute.  "If something happens very slowly over quite some time, maybe over decades, the different parts of the brain take up functions that would normally be done by the part that is pushed to the side," he added. 

Source: stuff.co.nz 22 July 2007

_Single Brain Cell's Power Shown

_ There could be enough computing ability in just one brain cell to allow humans and animals to feel, a study suggests.  The brain has 100 billion neurons but scientists had thought they needed to join forces in larger networks to produce thoughts and sensations.  The Dutch and German study, published in Nature, found that stimulating just one rat neuron could deliver the sensation of touch.  One UK expert said this was the first time this had been measured in mammals.

The complexity of the human brain and how it stores countless thoughts, sensations and memories are still not fully understood.  Researchers believe connections between individual neurons, forming networks of at least 1,000, are the key to some of its processing power.  However, in some creatures with simpler nervous systems, such as flies, a single neuron can play a more significant role.  The latest research suggests this may also be true in "higher" animals.  The team, from the Humboldt University in Germany and the Erasmus Medical Centre in the Netherlands, stimulated single neurons in rats and found this was enough to trigger a behavioural response when their whiskers were touched.

A second research project from the US suggests the computational ability of the brain cell could be even more complex, with different synapses - the many junctions between neurons and other nerve cells - able to act independently from those found elsewhere on the same cell.  This could mean that, within a single neuron, different synapses could be storing or processing completely different bits of information.

Dr Douglas Armstrong, the deputy director of the Edinburgh Centre for Bioinformatics, said the research did not mean all neurons had an individual role to play but that, in some instances, they might be capable of working alone with measurable results.  He said: "The generally accepted model was that networks or arrays make decisions and that the influence of a single neuron is smaller - but this work and other recent studies support a more important role for the individual neuron.  These studies drive down the level at which relevant computation is happening in the brain."

Source: news.bbc.co.uk 22 December 2007