Theos-Talk Archives (November 1999 Message tl00280)

Hello,

There is some interesting new research about to be published within the
next two years.  The question that has been experimentally tested is
whether all mental events are physical or not, or rather, is there physical
evidence for there being non-physical processes.

Now obviously we know little, in science, about the phenomenology
of mental events.  But we don't have to know.  All we need to know
is the processing speed of the human brain.  If we find that a human
can complete a mental task, such as a pattern recognition or
problem-solving task, that has been designed, per hypothesis, as
one that could not be completed in a given amount of time if all
the "mental processing" of it was a physical process, then there is
some indirect physical evidence of "mental events," so to speak,
not bound by the physical "speed limit," so to speak.  Again, without
getting too technical, a few clarifications might be in order.

The expression "processing speed" is vague.  Since events in the
brain are not that well mapped (hardly at all), how can we coherently
speak of processing speed.  An analogy with computers may help.

When speaking if the "speed" of a computer, one is speaking either
equivocally or one is speaking about one of two separate things.  In
computer engineering, "speed" is either "processing speed" or
"through-put."  Processing speed is a measure of how quickly any
task is completed, from start to finish, by the CPU.  Through-put is
how many tasks a computer can perform in a given time.  Now,
you can increase throughput (but not processing speed) by adding
CPUs for parallel-processing.  Given more processors, a computer
can complete more tasks (doing more than one at once) even though
the processing speed of each CPU remains the same.  But if one
designs a faster processor (i.e., one with a faster processing speed),
one can increase both processing time and throughput.  Now there are
other factors involved on a computer's "speed."  For example, I/O
devices hamper "speed."  Why?  Because a signal takes a certain
amount of time to transverse a certain distance.  The distance to
and from the primary I/O devices, namely keyboard and monitor,
cannot be practically closed (if humans are going to use the computer).
So, the time it takes, on average, for signals to transverse that
distance to and from cannot be shortened significantly.  Similar
constraints apply to accessing CDs, Disks, and tape.  Miniaturization
has allowed an increase in speed simply for the simple fact that
we are talking about a smaller space and thus time for a signal
to transverse between components.  The old vacuum tube or
even transistorized computers had not even a ghost of a chance
of being as fast as today's machines because of the distance/size
of components through which a signal travelled because longer
the distance the longer the time.  There are some new emerging
speed constraints with the issue of how miniaturized can we
get with silicon.  Silicon was chosen because it retains its
semi-conductive properties at a microscopic level (i.e., in
effect, two conducting paths can be extremely close together
without "short-circuiting" each other - to speak roughly).
But the calculated limits of how small a silicon chip can get
before its semi-conductivity breaksdown is already know and
the hunt for a new semi-conductive material is underway (although
it will be some time before this becomes a real worry).  But, it
will always remain an invariant limit, no matter how much
miniaturization there is, that the time it takes a physical
signal to transverse any amount of space, no matter how
small, has an upper limit (i.e., speed of light).

So, what does all this reflection on computers, speed, and
distance have to do with the brain?  Plenty, the brain is a given size.
Its neurons are of a given size.  The length of the neural
nets from brain to body is of a known given size.  Compared
to the modern cpu, the brain, neuron, and nervous system
are rather large.  So, the time it takes a signal to physically
transverse a distance is longer if the distance is longer.  But
we need to look at material also.  A nerve fiber consists of
a mixed solution of ordinary salt (sodium chloride).  So,
there is sodium, potassium, and chloride ions in the
nerve fiber.    Sodium and potassium ions are positively
charged.  Chloride ions are negatively charged.  Given
that there are more chloride ions, the rest state of a nerve
fiber is negatively charged.  A nerve signal is a region of
charge reversal flowing through the fiber.  When a signal
reaches a synaptic knob, it emits a neurotransmitter that
travels to the next neuron to its dendrite or soma.  Anyway,
in human, this network is insulated by the fatty substance myelin
so that signals can travel without much interference even between
neurons.  Given these materials, the speed of a travelling neural
signal, in any and all neurons, is 120 meters per second.  So,
we can say that the "processing time" of a neuron is this speed.
The brain might have a faster through-put if it had something
like a parallel processing arrangement.  But still, assuming
that that might be the case, a minimum amount of time
can be calculated based on spaces signals have to travel
at 120 meters per second.  So, given that number, tests
can be preformed even at our limited level of knowledge.

So, for example, there is a minimum amount of time that it
takes for a signal to transverse the optic nerve from retina
to brain, and so on.  Given a vague knowledge (but enough)
of how the brain is organized (in terms of charge patterns
during kinds of activity) and even taking into account the
possibility of something like parallel processing in the brain,
and despite our huge ignorance about much of how the brain
works, we still know the time a given signal takes to transverse
a certain physical distance.  With this knowledge alone, despite
all the things we don't know, a group of physicists and
neurophysiologists were able to come up with tasks that it
would be physically impossible for the brain to complete
within a given amount of time as well as events that should
be too fast to be a registered event for the brain.  Again, the
question was are there non-physical mental events.  On the
assumption that everything was physical, that mental events
were physical (even if we don't know how they are neurally
realized), certain assigned tasks could not be accomplished
in a given amount of time.

Without getting into someone else's research, they studied
advanced meditators (who had been found in late 70s and
early 80s to have ability to increase "information-processing
speeds and problem-solving speeds and for the mathematically
trained, computational speeds because while the early stages
of meditational practice attempt to become more focussed
and aware without thought, distraction, etc., at the advanced
level the awareness part of mind and the problem-solving,
conceptualizing, analyzing, and reasoning part are
re-integrated in a way that mutually enhances these opertations.
Awareness becomes sharper and clearer as if the logical part
were a lens while the logical part is clearer, faster because
less distracted, and tighter in its exactitude in tracing a
line of implication).  They also studied advanced meditators
who were advanced martial arts masters.

What they found was that in some instances, given the
speed of 120 meters per second for a neural signal, given
the length a signal would have to transverse from eye to brain,
across physical distances between parts in brain (even on
the assumption of parallel processing), and length of neural
connection between eyes, brain, and hands and feet (for
martial artists' tests), the response time and or
information-processing time to a task or problem or stimulus,
took less time than it should have if all processes involved
were physical.  Something happened or some phase of
whatever was going on inside their heads violated, so to
speak, the physical "speed limit."  Most conclude that
that since everything physical obeys the "speed limit"
and/or the "speed limit" defines the physical that there
were some non-physical events that took place in these
tests.   There is a British physicist that thinks otherwise.
He claims that some physical events DO violate the
physical speed laws (i.e., quantum events in EPR
experiments).  Penrose has commented that this might
not necessarily be evidence of non-physical mental
events, but rather, that some mental events or some
aspects of them might be quantum events displaying
some of the properties of the EPR experiments.  But
in my opinion, this is even a stranger view, in its
ramifications, than admitting the existence of the non-
physical.

Grigor Ananikian