IUBio Biosequences .. Software .. Molbio soft .. Network News .. FTP

Percentage of brain used for conciousness?

Guy Lux guyscarsbrook at hotmail.com
Fri Jan 9 05:08:31 EST 2004

r norman <rsn_ at _comcast.net> wrote in message news:<graovvcfc55jmdslf159btpg32npusqvgk at 4ax.com>...
> On 7 Jan 2004 07:29:00 -0800, guyscarsbrook at hotmail.com (Guy Lux)
> wrote:
> >Reading that the brain makes 100 trillion calculations per second
> >(relaxed state or at peak?) and that a new Linux supercomputer will be
> >able to make 11.1 trillion calcs a second, could anyone hasard a guess
> >as to what percentage of the brain's 100 trillion calculations are
> >used for pure conciousness as opposed to movement, sensitivity and
> >some of the more basic functions like breathing and heart control?
> >
> >If 11.1% or less is used for consciousness, why could this new
> >computer not become consious?
> >
> >And would a healthy, developed, conscious part" of the brain be
> >considered a conscious entity, if it had never had any sensory input.
> >
> >What sort of input would a brain/supercomputer need in order to become
> >conscious?
> >
> There are several problems dealing with the questions you ask.
> First, what is a "calculation" in a computer?  Do you know so
> precisely that you can say for cetaintly to three significant figures
> exactly how many a computer can do?  Is it a floating point
> calculation?  Is it a machine instruction?

Good point, I hadn't thought there were different types of
calculation, I will do some research as to what diffrences there are
between a brain calculation and a machine calculation.
> Second, what is a "calculation" in a brain?  Whatever the answer is
> for a computer, there is no analogous concept for a brain.  It does
> not make any sense to say that a single neuron is making x number of
> calculations in one second. Is it related to action potentials?
> Probably most neural integration is completely graded in microcircuits
> and has nothing to do with action potentials.  These are analog
> running in continuous time.  The concept really doesn't make sense.
> Yes, people do throw out numbers like the 100 trillion figure, but
> that doesn't mean that the number has any significance.  Are
> "computations" part of what microcircuits or even individual synapses
> do? or do major dendritic branches do it? or whole neurons? or neural
> complexes?  How could you even begin to count?

Yes, I had read this 100 trillion figure in so many places that I had
not really thought about how it was calculated.  I think when I read
up about diffrenent types of calculation I will realise the difficulty
in estimating the speed/ability of brains/machines.

> Third, what is "consciousness"?  We really don't have a clue so it is
> impossible to describe "what percentage" of the brain is needed to
> make it happen.  Is it raw computing power?  As far as we know, there
> is no molecular or cellular machinery working in human brains (that
> supposedl have consciousness) that does not also work in insect or
> slug or whatever other type of brain you can think of (that supposedl
> don not have consciousness).  As a result we conclude that, since the
> main difference is the size of the brain, then size must be important.
> Still, there are animals with larger brains than our own. Does that
> automatically make them conscious?  Almost no one believes that.

I agree that conciousness is very difficult to pin down as a concept,
But I think you will agree that there are parts of the brain which
have nothing to do with consciousness. Regions that concern sight,
hearing (etc etc) have been identified and so I thought it might be
possible to hasard a guess by striking certain areas off the list of
parts responsable for consciousness).  BTW, are those having undergone
a frontal lobotomy considered conscious?)

Regarding brain size, I think that we can say that as humans, we have
the largest cerebrum which I think I'm right in saying is the part
generally considered to relate to consciousness?)

> Furthermore, whatever consciousness is, it is not simply raw machine
> computational power, but must be something about how that power is
> used.  For example your supercomputer, no matter how powerful, is
> totally incapable of solving a weather simulation or nuclear reactions
> or generating a fully animated video scene or anything else unless it
> is programmed to do so.  Further, none of these situations requires a
> supercomputer in a theoretical sense. With a small, slow computer, it
> just takes longer to do the job.  Is consciousness a problem that
> requires, for some fundamental reason, massive computational power or
> is it simply something that runs too slowly to be useful on a small
> system?  We have no clue.

I agree with you about "how the power is used".  I think you are right
to question whether is is raw computing power and think it is far more
to do with programming and input. I can't imagine how many things a
baby learns (learing = self programming?) in its very first year. 
(When are children considered conscious? New borns no, but by about 1
year?  Sorry if this offends any one!)  If all those millions of self
programmed rules could be fed into a computer could it then become
conscious?  Who knows?  Whatever the answer, the whole debale seems to
be more about the programming than computational power.

> Most concepts of consciousness  -- there is a very large literature in
> the realms of neurology, psychology, cognitive science, and philosophy
> that you should consult -- indicate that it is necessarily related to
> integrating a sense of "self" with the experience of behavior in the
> world. That is, you do need to have available sensory information
> about what is happening in the world and also how your own actions
> modify what happens in the world.  So without any sensory input, there
> really could't be consciousness in the form we usually consider.
> Exactly what it would take to produce machine consciousness, or even
> if that is at all possible, is far from being answerable at present.

Thanks R for replying to my question, I appreciate your help.  I love
these sort of questions, but work in finance......


More information about the Neur-sci mailing list

Send comments to us at biosci-help [At] net.bio.net