[extropy-chat] Wetware vs. Hardware (was IQ vs Upload)

[Dirk Bruere]

The Avantguardian wrote:

>--- Dirk Bruere <dirk at neopax.com> wrote:
>
>  
>
>>The Avantguardian wrote:
>>
>>    
>>
>>>    I have done some back of the envelope
>>>calculations to try to answer my own questions on
>>>      
>>>
>>this
>>    
>>
>>>matter. If we have 10^12 neurons with 10^4
>>>      
>>>
>>connections
>>    
>>
>>>per neuron, the total connectivity of the human
>>>      
>>>
>>brain
>>    
>>
>>> 
>>>
>>>      
>>>
>>A better estimate would be 10^11
>>And we can probably say that less than 10% of those
>>are involved in 
>>'intellectual' processes.
>>    
>>
>
>The parts of the brain involved in 'intellectual'
>processes can only work because they are built on many
>'sub-intellectual' layers. You can't just peel the
>cerebral cortex off someones brain and expect it to
>still retain consciousness. Also you sound like the
>'we only use 10% of our brains crowd.' The latest
>reasearch using advanced imaging techniques seems to
>suggest that yes only 10% of our neurons are active at
>any one time but that 10% changes depending on what we
>are doing and experiencing so it is a like a 'shift'
>of neurons on the job and these 'shifts' switch in and
>out over the course of a day. 
>
>  
>
http://flatrock.org.nz/topics/science/is_the_brain_really_necessary.htm

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 noninvasive measurement of radio density known as 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:

bullet 	those with nearly normal brains
bullet 	those with 50-70% of the cranium filled with cerebrospinal fluid
bullet 	those with 70-90% of the cranium filled with cerebrospinal fluid
bullet 	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."


-- 
Dirk

The Consensus:-
The political party for the new millenium
http://www.theconsensus.org



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