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Fig. 1.17 Abstracting the
digestive system, the ancient
gut around which we are built,
creates an interesting shape,
but does not show us the
shape of the entire body.
(Reproduced with kind
permission from Grundy 1982.)
terms: the nervous system, the circulatory system, and
the fibrous (fascial) system - an idea, we must admit, so
unoriginal that Vesalius, publishing in 1548, rendered
versions of each of them. We will examine each of these
in turn (in full knowledge that they are all fluid systems
that are incompletely separate and never function
without each other), before going on to look at their
similarities and specialties, and speculate on their place
in the somatic experience of consciousness.
The neural net
If we could make everything invisible around it and
leave the nervous system standing as if in life (a tall
order even for magic, considering the nervous system's
fragility), we would see the exact shape of the body,
entirely and with all the individual variations (Fig. 1.18).
We would see the brain, of course, which Vesalius unac-
countably omitted, and the spinal cord, which he left
encased in the vertebrae. All the main trunks of the
spinal and cranial nerves would branch out into smaller
and smaller twigs until we reached the tiny tendrils
which insinuate themselves into every part of the skin,
locomotor system, and organs. Vesalius presents only
the major trunks of nerves, the smaller ones being too
delicate for his methods. A more modern and detailed
version, albeit still with only the major nerve trunks
represented, can be seen in the Sacred Mirrors artwork
at www.alexgrey.com.
We would clearly see each organ of the ventral cavity
in the filmy autonomic system reaching out from the
sympathetic and parasympathetic trunks. The digestive
system is surrounded by the submucosal plexus, which
has as many neurons spread along the nine yards of the
digestive system as are in the brain. 3 8 The heart would
be particularly vivid with the bundles of nerves that
keep it tuned.
Of course, this system is not equally distributed
throughout; the tongue and lips are more densely inner-
Fig. 1.18 It is amazing, given the methods available at the time,
that Vesalius could make such an accurate version of the delicate
nervous system. A modern and strictly accurate version of just this
system would not include the spine, as Vesalius did, and would, of
course, additionally include the brain, the autonomic nerves, and
the many finer fibers he was unable to dissect out. (Reproduced
with permission from Saunders JB, O'Malley C. Dover
Publications; 1973.)
vated than the back of the leg by a factor of 10 or more.
The more sensitive parts (e.g. the hands, the face, the
genitals, the eye and neck muscles) would show up with
greater density in our filmy 'neural person', while the
otherwise dense tissues of bones and cartilage would be
more sparsely represented. No part of the body, however,
except the open lumens of the circulatory, respiratory,
and digestive tubes, would be left out.
If your nervous system is working properly, there is
no part of you that you cannot feel (consciously or
unconsciously), so the whole body is represented in this
network. If we are going to coordinate the actions of
trillions of quasi-independent entities, we need this
informational system that 'listens' to what is taking
place all over the organism, weighs the totality of the
many separate impressions, and produces speedy coor-
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