Humans use 10% of brain... true?

Martin Knopman mknopman at worldnet.att.net
Thu Aug 26 04:53:25 EST 1999


Jaimie Polson wrote in message ...
>In <7q2iee$cvd$1 at bgtnsc01.worldnet.att.net> "Martin Knopman"
<mknopman at worldnet.att.net> writes:


>>Well, lets see.  The brains produces neural output for muscle contractions
for
>movement, breathing, maintenance of blood pressure, heart rate.  There's
>regulation of glandular sectretions, regulation of body temperature....
etc.
>This is all vastly different from "thinking some average thought".
>

That, my dear is computation you are describing.  Why you imply that
computation in the brain relates only to thinking is quite beyond me.  A
computer computes, although it regulates only what would be called
involuntary actions.  Computation and thought are separate notions.

>
>And I am not making any assesment of the proportion of brain used by man. I
>have no idea.  As I said before, this idea of 10% is likely based on
>neuronal numbers.  "How much brain do we need to function normally?"
>

I don't think you have any idea what this '10%' means.  I don't think anyone
does, which is why I said it was a stupid statement.  You seem to be
acquiescing to that here, but with lingering resistance, for some odd
reason.  Why don't you just admit that the myth makes no sense?


>
>>>And most of
>>>the brain's functions work pretty well, even if you haven't had an
average
>>>amount of sleep.
>
>>Yes, my thinking is always clear after 30 hours without sleep.  I always
>>think best when I'm in a pressure situation, or when I'm depressed, or
when
>>I'm scared,...  Come on.
>
>
>As I said, most of the brain's function is not "thinking".  Clearly is
>is harder to think when we are tired, but I don't think its harder to
>maintain our blood pressure or regulate our body temperature.
>
>

But, if one of the functions of the brain that we have some personal access
to - thinking - degrades with lack of sleep or emotional disturbances, would
it not be fair to assume that other functions are similarly effected?  Do
you actually believe that all of your physiology remains unaffected by these
conditions? ... that sleep is something required only by the thinking part
of the mind?  ... that physical reactions to stress, such as not being able
to catch your breath are ... what did you say again?  You don't think that
the regulation of blood pressure is affected by these situations ... do you
speak publicly much?  How is it that emotions, such as fear, anxiety,
happiness are manifested in you?  Do these not have physical cues that alert
you to their presence ... as with every other human on the planet?

>
>Raw neuronal usage (electrical activity, action potential, ionic
conductances,
>whatever) is what neurons do.  To measurement  this would answer the
question.
>Does the brain only use 10% of its capacity?  It suggests if we remove the
>other 90%, that we would function normally.  How do you measure it?  No
idea.
>

"Raw neuronal usage ... is what neurons do."  This is what they call a
tautology, except for a slight semantical problem.  When you say "the other
90%" I have no idea what you mean.  The other ... as opposed to what?  And
this "function normally" means nothing to me.  And again, if you admit that
you have no idea how to measure 'it' then why try to explain how to measure
'it'?  Do you have an idea about it or not?

>>
>I was not making the assumption that all neurons are used constantly.

You said, "I think the question is pretty simple.  You have 100 neurons in
your brain and you use 100 of them (for what ever function).  QED 100%
usage.   You use 10 of them, then 10% usage."

I don't see any reference here to use over time.  You only talk about use,
or don't use, which implies time independence which implies always.  It is a
highly simplistic answer that carries no meaning.  I attached the time
reference to it to lend the smallest amount of worth to the statement.  As
it stands it says nothing.  Oh, by the way, I would advise you against using
"QED" in this context.  You have nothing even remotely resembling a proof,
and QED is not for definitions.  But if you did it would be '100% usage
QED'.


>Just
>that they are used (thinking neurons are used when you think, muscle
neurons
>are used when you contract muscles, neurons in a neuronal network
oscillator
>are used whenever.  Clearly neurons are quiescent at times, and active at
>other times (the time scale varies, depending on the neuron)).  But are
some
>neurons always quiescent?  Probably impossible to answer.
>
>

I don't believe that you really understand the original question, or the
notion of functional capacity.


>
>I've chopped out the rest of your discussion for brevity.   Your argument
>is about what is usage and capacity.  By your definition, 100% capactiy
would
>mean all neurons firing together all the time.

If you are going to put words in my mouth please get them correct.  That
definition was my impression of your statement, which I explained above.  I
have said, time and again, that the notion of capacity for a complex system
is very hard to define with any great degree of accuracy, and impossible for
us to do for the brain at this point.

>My definition is that
>100% capacity is that all neurons have an function that they fulfil at
>some time.  They do not need to be always active.  They may only be
>active under certain special circumstances.  But they have a function
(other
>than just filling up the skull or as cat food).

All neurons are living cells, which means that they interact with their
environment throughout their lifetimes, which means that they are certainly
functional to their environments ... whether you are impressed by that
functionality or not.


>
>Clearly in either definition the idea of 100% capactiy is not likely (at
>the very least due to redundancies in the system).
>
>I think my definition is what people are normally referring to when they
>talk about brain capacity (10% or whatever).
>
>
>>> I suppose
>>>this kind of statement comes from knowledge of various insults to the
>>>brain - small stroks, brain surgey, injury etc that do not appear to
effect
>>>our functioning.
>
>>I do not agree with that statement.  I don't know of anyone who claims
that
>>a small stroke has no effect on brain function.  It is one thing for
someone
>>to appear normal after a stroke, but quite another to claim that their
brain
>>function has not changed.  As I mentioned above about error correction and
>>such, any robust complex system must have certain redundancies built into
>>it, but that does not mean that those redundant functional structures
could
>>just be utilized at any time.
>
>Okay, one more point.  I did not say this was true, I said it was an
>basis for this kind of question to be asked.  But then consider, if you
>lose one brain neuron does it affect your normal function?  Or if you lose
>10 neurons?  Or 100, 1000, etc.
>

Yeah, so what?  If you lose one arm you can still function normally.  Does
that mean that we utilize only 50% of our arm capacity????  Or if you lose
one eye....??

Peace,

Martin Knopman





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