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Is your brain really necessary?
Do you really have to have a brain? The reason for my apparently
absurd question is the remarkable research conducted at the
University of Sheffield by neurology professor John Lorber.
When Sheffield's campus doctor was treating one of the
mathematics students for a minor ailment, he noticed that the
student's head was a little larger than normal. The doctor
referred the student to professor Lorber for further examination.
The student in question was academically bright, had a reported
IQ of 126 and was expected to graduate. When he was examined by
CAT-scan, however, Lorber discovered that he had virtually no
brain at all.
Instead of two hemispheres filling the cranial cavity, some 4.5
centimetres deep, the student had less than 1 millimetre of
cerebral tissue covering the top of his spinal column.
The student was suffering from hydrocephalus, the condition in
which the cerebrospinal fluid, instead of circulating around the
brain and entering the bloodstream, becomes dammed up inside the
brain.
Normally, the condition is fatal in the first months of
childhood. Even where an individual survives he or she is usually
seriously handicapped. Somehow, though, the Sheffield student had
lived a perfectly normal life and went on to gain an honours
degree in mathematics.
This case is by no means as rare as it seems. In 1970, a New
Yorker died at the age of 35. He had left school with no
academic achievements, but had worked at manual jobs such as
building janitor, and was a popular figure in his neighbourhood.
Tenants of the building where he worked described him as passing
the days performing his routine chores, such as tending the
boiler, and reading the tabloid newspapers. When an autopsy was
performed to determine the cause of his premature death he, too,
was found to have practically no brain at all.
Professor Lorber has identified several hundred people who have
very small cerebral hemispheres but who appear to be normal
intelligent individuals. Some of them he describes as having 'no
detectable brain', yet they have scored up to 120 on IQ tests.
No-one knows how people with 'no detectable brain' are able to
function at all, let alone to graduate in mathematics, but there
are a couple theories. One idea is that there is such a high
level of redundancy of function in the normal brain that what
little remains is able to learn to deputise for the missing
hemispheres. Another, similar, suggestion is the old idea that
we only use a small percentage of our brains anyway -- perhaps as
little a 10 per cent.
The trouble with these ideas is that more recent research seems
to contradict them. The functions of the brain have been mapped
comprehensively and although there is some redundancy there is
also a high degree of specialisation -- the motor area and the
visual cortex being highly specific for instance. Similarly, the
idea that we 'only use 10 per cent of our brain' is a
misunderstanding dating from research in the 1930s in which the
functions of large areas of the cortex could not be determined
and were dubbed 'silent', when in fact they are linked with
important functions like speech and abstract thinking.
The other interesting thing about Lorber's findings is that they
remind us of the mystery of memory. At first it was thought that
memory would have some physical substrate in the brain, like the
memory chips in a PC. But extensive investigation of the brain
has turned up the surprising fact that memory is not located in
any one area or in a specific substrate. As one eminent
neurologist put it, 'memory is everywhere in the brain and
nowhere.'
But if the brain is not a mechanism for classifying and storing
experiences and analysing them to enable us to live our lives
then what on earth is the brain for? And where is the seat of
human intelligence? Where is the mind?
The only biologist to propose a radically novel approach to these
questions is Dr Rupert Sheldrake. In his book A New Science of
Life Sheldrake rejected the idea that the brain is a warehouse
for memories and suggested it is more like a radio receiver for
tuning into the past. Memory is not a recording process in which
a medium is altered to store records, but a journey that the mind
makes into the past via the process of morphic resonance.
But, of course, such a crazy idea couldn't possibly be true,
could it?
