1. Ventricles and the CSF-liquid:

In the evolutionary development of the brain the ventricles and their shapes could have been an equally decisive factor as the development of neural mass, this with dimensional views applied to the design. Compare mass - space as poles of d-degree 3 with neural mass versus ventricles.

Evolutionary development of lateral ventricles in forebrain, cross-section, left and right cerebral hemisphere:

A simplified sketch after Kz p. 250-251:

   

Fig Ns-37-97-1

- Salamander: ventricles along longitudinal axes of the body - as d-degree 4.
- Reptile: a polarization towards perpendicular relation through a step d- degree 4 →> 3 (radial - circular as geometric poles of d-degree 3).
- Primitive mammal (Solenodons, a kind of mouse): whole ventricle turned 90o - as through next step 3 →> 2.
- Humans: an inversion convex - concave of the half circles - as in a d-degree step 2 - 1.
   (It could be said that shape of the hemispheres simultaneously develop towards increasing number of "sides", from "two-sided" in salamanders, "3-sided" in reptiles, "4-sided" in Solenodons to approximately semispherical in humans.)

The ventricles 4, 3 and 2 in humans has shapes that roughly illustrates the geometries of corresponding d-degrees in the dimension model - with increasing size:

Fig Ns-38- 97-2

- 4th ventricle: along the axes F-B, front-back, a widened canal with a little polarization dorsal - ventral direction as between poles 00 - 0.
- 3rd ventricle: a widened space volume.
- 2nd ventricles, division in two, bows surrounding 3rd ventricle as "shells" around a central room.

Related parts of neural brain:
- Hemispheres of cerebrum around the 2nd ventricles.
- Diencephalon around the 3rd ventricle.
- Mesencephalon around the canal between 4th and 3rd ventricles.
- Medulla oblongata with pons on ventral side and cerebellum on dorsal side of the 4th ventricle.

The central canal of the spinal cord as a cavity is at start of the embryological development a built-in surrounding, an insubstantial space, which widens and develops into design of the ventricles, of the embryo, i.e. anticenter at the animal pole that gets enclosed when the neural plate invaginates to the neural tube, in positions a pole exchange ac - c, mass - space:

   Fig Ns-39-098-1

The spinal canal with CSF becomes the opposite pole to the neural mass around it. As a primary anticenter it could perhaps be suspected that the CSF chemically induces such polarizations as for instance the transverse bands on the spinal cord and divisions in brain bladders (?). Cf. 00-pole as a first polarizing force in the model here.

While the canal with CSF develops stepwise to the central ventricles, it takes a side-way too at 4th ventricle to circulate anticentrically around the whole brain, a polarization c - ac in relation to inner ventricles.
   It's notable that this branching occurs in the 4th ventricle and in its ceiling and dorsally (the anticenter side deriving from first animal pole) and through 3 small holes (foramina). It illustrates how a step from d-degree 4 to a geometry of d-degree 3 can be expressed biologically.
   We have in the dimension model that the 00-pole may be regarded as debranched, meeting "the other way around" in a haploid chain, inwards to circular pole 3a:

      Fig Ns-40-98-2

Another expression for the primary character of inward direction of CSF is that it's produced in inward - backward direction from the ceiling of 3rd ventricle, the floor of 2nd ventricles (hence in step 3 - 2).
   It is non-neural tissue epithelium, dorsally in the neural tube in forebrain and diencephalon that has been displaced inwards towards the inner ventricles and has become gland epithelium for the production of CSF (Kz p. 242). Hence, in several respects expression for anticenter and inward direction.

In the relation neural tissue - CSF we have naturally also a relation between phases, between organic matter and liquids of the kind that can be described as 3- to 2-dimensional with regard to chemical bonds. (Content of proteins etc. in the liquid here neglected.)
   CSF contains more of Na+ ions than other extracellular liquid, which could be a sign of its origin from outer surrounding of the embryo?

The relation CSF-canal — surrounding neural mass can be compared with the elevator versus stairs in a building (possibly both chemically and psychologically). Also a relation continuum - quantum jumps.

"Reissners thread" is a mysterious line of glycoproteins with unknown function that goes from secretory cells in diencephalon backwards through the whole CSF-canal. It's believed to serve transport of molecules. It could be regarded as one expression for the main coordinate axis F - B. Perhaps it corresponds to "the other way around" in the figure above! It's only absent in primates, which eventually could have connection with the loss of a (real) tail?
   (It seems as if a part of this fiber (RF) could have an impact on outgrowth of axons in e.g. chicken embryos (http://www.springerlink.com/content/n80v070740616q62/).

According to information some decades ago it seemed to be internal secretion of substances from the circulating CSF-liquid into the brain that induces sleep, among other molecules GABA (γ-Aminobutyric acid). Together with the neural center for sleep in medulla oblongata, it illustrates the double-direction 00 <=====> 0 inwards-outwards during sleep: the phase for animals as "whole worlds" or entities in themselves, both centers and anticenters.

2. Brain parts:

§It can be noted that the number of bladders on front part of the neural tube that develops to a brain is 5 already on an early evolutionary stage of craniates, 5 with the widening of medulla oblongata: in number corresponding to steps in the dimension model.
   After a rearrangement to 3 and new differentiations the bladders become these 5 well known parts of a human brain:

Fig Ns-41-99-1

(Figures are preliminary identification of d-degrees, more closely commented below.)

The long evolution of the nervous system is similar to other organs as the blood system: a development 0 → 1 → 2 → 3 in dimensions from single neurons to a "linear" tube to wavy forms with curves (concave - convex) to a more and more centralized mass.
   From spinal cord to the brain there is a rearrangement of neurons from the "linear" order in columns to an arrangement in separate, more centralized nuclei, also a dimensional development towards d-degree 3 on the neuron level.

The prolongation of the neural tube to the brainstem can be regarded as a center in the centralized mass of the brain - with root in the body.
   A general principle is that integrating centers lie deeper down with increasing differentiation outwards the surfaces.

a) Medulla oblongata and Pons:

Some of the functional centers mentioned below are actually located to Pons on the ventral side of medulla (Wikipedia and earlier sources).

Medulla oblongata around the 4th ventricle contains the reticular activating system RAS (ascending part ARAS) - with a general, unspecific and divergent spread of pathways upwards to the whole cortex for an arousal level and downwards for muscle tonus for instance. The neurons have extra richly branched axons.
   These systems become in the interpretation here an obvious expression for d-degree 4, the level of vector fields.

Centers for consciousness as such are located here but also for sleep, playing a role in generating dreams. Cf. sleep as pointed to above is a phase of two-way direction, d-degree 4 as only "virtually" polarized.
   Another example of the two-way direction is the center for respiration that regulates the breathing: in agreement with most other polarities inhalation ~ inwards: dorsal part of the center, exhalation ~ outwards the ventral part.
   Further, it's notable that the reticular formation contains centers for the basic directions in postures of the body and its balance around the center of gravity. It gives another example of the 4-dimensional character of this system.

The extrapyramidal tracts are chiefly found in the reticular formation of the Pons and Medulla. It's essential to underline that these tracts also have the ability to execute motions governed by the will (LEL p. 160). A will that comes from direction in this deep structure.

Furthermore, medulla includes centers for control of blood circulation and elementary digestive functions, thus also for the vegetative system.
   Several other sensory and motor centers are mentioned in Pons as for hearing, taste, eye movements and facial expressions.

In the "reticular formation" white and gray substance is not yet separated as in the forebrain but a network of closely integrated neurons and nuclei. Cf. polarizations as d-degree steps outwards the forebrain on this macro-scale on the tissue level.

It's also interesting - and not astonishing - that some relationship between RAS circuits and pathways for physiological pain has been found. Cf. about pain as one of the oldest and most general senses.

A last notice: The cranial nerve that governs the motor activity of the tongue emanates from a location furthest back in medulla oblongata. Cf. the connection between d-degree 4 in our model and d-degree 0/00 of motions with speech as the last in a dimension chain of psychological faculties.

b) Cerebellum:

It's original and basic function seems to be a sensory integration (pole 4a, inward direction in our model) when it concerns body positions (in 3-dimensional space) and motions, thus in agreement with its dorsal (~ anticenter) position. Cerebellum has also by several scientists been regarded as at bottom a sensory organ (Wikipedia): it receives the lot of inputs from both cerebrum and sensors from muscles in the body and has regulating, inhibiting functions.

The smallest region, the flocculonodular lobe, is mentioned as the oldest part in evolutionary terms, participating in balance and spatial orientation. Its primary connections are with the vestibular nuclei, the organ for equilibrium, although it receives visual and other sensory input too. Damage to it causes disturbances of balance and gait. Cf. gait with d-degree step 1→> 0/00 of motions in our model. (0 and 00 the outer poles defining d-degree 4.) It has 4 nuclei in the center that becomes 3 in mammals.
  The development of the hemispheres as 3-dimensional volumes occurs later during evolution in mammals.

The design of cerebellum is typically 3-numbered with 3 x 2 peduncles or stalks, 3 layers in its cortex (compared with 6 in cortex of forebrain), 3 coordinate axes in structure of this cortex, and not least its connection with the organ of equilibrium with its 3 arches.
   It's also said to have 3 representations of the body - compared with only 2 in the forebrain.  
   
Cortex of cerebellum differs in essential ways from cortex of the forebrain, which has cells arranged in "radial" columns.
   The big, integrating purkinje cells make up roughly only one layer. Their dendrites become an outer layer. A big amount of small granule cells inside the purkinje cells distribute input to these dendrites through branching, transversal axons, i.e. axons that become perpendicular, to the main radial input - output structure. It correlates with the postulated circular structure that pole 4a (inward direction) gets in d-degree 3 in the dimension model, the angle step from 180° to 90° of polarity in relation to pole 4b. 
   The fact that cortex as such in its macro-shape is much deeper furrowed than the wavy cortex of forebrain could depend on the polarizing force from anticenter, 00 and pole 4a being principally stronger in distal cerebellum. More of a vector field character inwards from anticenter is retained?

We may compare the function of cerebellum for body positions, closely connected with gravitation, and the pole 4a representing gravitation on the physical level and in the dimension chain of forces.
   There are two nuclei in the brain with a similar cellular design as cerebellum: the dorsal cochlear nucleus in mammals and one that receives input from lateral line organs in fishes (Wikipedia). Hearing (and equilibrium) organs of mammals have been regarded as developed from those lateral side lines. These organs are both senses for pressure, connected with gravity, the primarily inward direction of d-degree 4.

In all, as distal, mainly a sensory center, regulating and inhibiting motor activities and as such part of the primary motor ↔ sensory polarity (see Ns I, No. 1), cerebellum may be interpreted as an organ from step 4a ← 3 inwards in the dimension chain. Its system has also been described in terms of divergence - convergence, i.e. directions Vdiv Vconv, which are outer poles of d-degree 3 in our model.

Fig Ns-42

Fig Ns-43

(It may be added that granule cells of cerebellum make up about 3/4 of all neurons in a human brain (Wikipedia)! Input a manifold, output unity: also a relation between lower and higher d-degrees.

c) Mesencephalon - the midbrain:

The midbrain is small and positioned at the aqueduct between 4th and 3rd ventricles and is sometimes seen as a part of the brainstem. The reticular network reaches up in midbrain too.

It seems possible to see the relation midbrain - cerebellum as neural masses that correspond to the branching of ventricles or CSF-flows in the top of 4th ventricle:
- forward to the aqueduct to 3rd ventricle, corresponding to the central midbrain,
- sideways to the CSF-circulation around whole brain, corresponding to cerebellum with its mostly inhibiting function.
   Cerebellum is typically "debranched" and could in our model represent the 00-pole of d-degree 4 as debranched, meeting "the other way around" (figure below) - and hence developed later in evolution.

   Fig Ns-44-5-1

The general architecture of the human midbrain is shared with the most ancient vertebrates. Earlier, during history of evolution, before the craniates appeared, the mesencephalon seems to have been the front part of the brain, the center for sight, origin for eyes and smell organs. It's still the most front part of the brain in birds.

It's noteworthy that the whole diencephalon and forebrain have developed from the smell brain.
   Even in lower craniates the midbrain functions as an integration center for sensory sight and hearing, but later these functions was taken over by centers further towards the front. Such a fact that certain functions move forwards in the brain could illustrate how lower d-degrees originate from polarization of higher ones in our model.

In the midbrain motor and sensory centers become distinctly separated areas and centered nuclei. Arrangement is the usual with motor centers (~ pole 4b, outward direction) ventrally, sensory centers (~ pole 4 a, inward direction) distally around the aqueduct.
   (We could note that number 4 here appears also in the name of the sensory centers, the colliculus, called corpora quadrigemina: 2 for eye movements, 2 on ventral side of aqueduct for hearing.)

Below, in the ventral part of midbrain, the red nuclei with functions for motor coordination appear in illustrations as more or less circular centers, cf. 0-poles.    The difference to substantia negra should be noted: it starts below the red nuclei and have the form of more radial, divergent bands. This "substance" is perhaps best known as producer of the essential transmitter dopamine. Lesion in the function is connected with the motor disease Parkinson.    Dopamine, however, is also said to play a role in "motivation" of species, from humans to animals as insects.
   Hence, both in its shape and in function it seems as a prolongation associated with the outward direction of d-degree 4b, with efferent vectors from the RAS system in medulla oblongata: arousal, consciousness, potential action, with "will" in the deeper sense (cf. above about the extrapyramidal tracts in medulla oblongata).

The lateral axis has in midbrain been clearly marked with the doubling of all the mentioned centers and areas, while the reticular activating system also reaches up here. Cf. the identification of coordinate axes in Embryology with d-degrees 4 - 3 - 2:
   4: Distal - Ventral axis: Sensory - Motor directions.
   3: Front - Back: midbrain between medulla and diencephalon: halfway separation of sensory centers (sight - hearing) and of motor areas (red nucleus - substantia negra)?
   2: Left - Right: lateral axis, doubling of structures.
Why is the lateral axis, if representing d-degree 2, expressed already here? One aspect could be the loop version of the dimension chain where step 4 →> 3 through debranched degrees corresponds to step 2←1. Another that midbrain earlier was the front part of the brain and as such included next steps too.

   Fig Ns-45

Fig Ns-46

d) Diencephalon:

Geometrically the diencephalon represent the step where transition to 2 hemispheres occur and the step from the "circular" 3rd ventricle as a room to half-bows of 2nd ventricles. (The lateral axis gets further expressed with the temporal lobes of the forebrain.)

Diencephalon seems to make up an inner brain in itself with the poles 3b-3a:
- Radially, from the two symmetric thalamus structures as centers, relaying nervous signals motor and sensory signals divergent / convergent to/from the whole cortex of forebrain with neocortex.
- Circularly there is the several parts of the limbic system above, around and below the 3rd ventricle: for instance the bows of Hippocampus and of Fornix as a C-shaped bundle of nerve axons from hippocampus to hypothalamus and the similar shape of Stria terminalis. Further cortex of the cingulate gyrus, above corpus callosum, the transverse bundle of fibers that connect the two hemispheres.
   (To this come secondary, centric bodies as Amygdala and the Mamillary body.)

The cortex of cingulate gyrus as an inner one compared to neocortex of the forebrain is not convoluted, and its gyri are vertical ("parasagittaly"), while gyri of neocortex are transverse. The vertical type is observed in non-primate species and hence regarded as older in evolution (Wikipedia).
   Both these differences imply a d-degree step in our interpretations here, from the radial - circular polarity in step 3 - 2, to the wavy form of neocortex, implying a polarization of d-degree 2 in convex - concave. Simultaneously it's an angle step, here vertical to transverse planes.

One essential aspect is that here in diencephalon - as in a middle step - the meeting of the basic nervous and endocrine systems occurs, systems from primary animal and vegetative poles A - V:
- dorsally in epiphysis (pineal gland) which earlier in evolution was a median eye, a photoreceptor in lampreys for instance, now in humans is a light-dependant producer of melatonin that have with sleep and seasonal regulation to do,
- ventrally in hypothalamus with hypophysis, which produces neurohormones for the autonomous inner system, regulating e.g. hunger, thirst, body temperature etc., functions of the digestive, vegetative system.
   Thus, this polarity reflects primary directions A-V: from outside environment inwards in dorsal pineal gland, from inside the body outwards (forwards) to the ventral gland hypophysis-hypothalamus.
   The fundamental coupling in these glands between chemical and electric communication, hormones via blood system versus nerve signals, is a polarity which can be associated with mass and structure (d-degree 3) and covalent bonds on one hand and charge (d-degree 2 in our model) and metal ions on the other.
   The smell organ with the olfactory tract connects here, with its enormous chemical differentiation ability.

Regarding the function of diencephalon, different parts of it are involved in memory creation and storing.
   It's noteworthy that it especially concerns memories for spatial orientation, i.e. the 3-dimensional room, and memories for places, in agreement with our dimensional interpretations here.
   Probably sensory information from different areas of neocortex get connected here and generally it's a well known experience that memories need an associative "context" to reappear. Sensations of smell do often awake memories, cf. the olfactory tract here.
   Memories as stored "inwards" could have a parallel in the storage of DNA with methylated T-base inwards from RNA on the genetic level.

Further, elementary emotions are located to centers here. It's also obvious that essential emotional experiences influence memory storing.
   First such emotions are mentioned in terms of "fight or flight" (see about Lorenz), which can be translated to directions outwards/inwards, the outer poles 4b - 4a of d-degree 3 in our model.
   There are also centers for pleasure that activates a repeated reward behavior, which could be described as a kind of "circular" repetition.
   Another aspect is that many emotions implies polarizations such as openness - closeness, good - bad, negative - positive and in this sense reflect the property of charge as a physical quantity, in the dimension model assumed as a quality of d-degree 2.

e) Forebrain with neocortex:

In the forebrain , newer in evolution, the polarity radial - circular geometry appears clearly on the tissue level as a separation between inner, radial white matter of nerve fibers and outer "circular" surface of gray matter, the cell columns.
  The surface (d-degree 2) gets wavy, meandering as described above, (poles convex - concave and inside - outside of d-degree 2).
   Transverse fibers along the surface of circumference connect its different areas.

      Fig Ns-47-99-2

The forebrain as a whole can be regarded as a circumference, a layer around diencephalon as a central mass/space structure. As mentioned above about cerebellum the growth of cortex of cerebrum (telencephalon) on the embryonic stage is also circular (Fc p. 353) as a process around a center. It has been described as upwards on the ventral side, circular around the front and backwards on the dorsal side, in agreement with first directions of vegetative - animal poles when turned to a back - front axis.

Brain parts in d-degree steps:
      Fig Ns-48

Cortex of forebrain:

The lateral furrow on top divides the primary motor and sensory centers in accordance with the general, functional coordinate axes: ventral side for outward direction becomes the motor area and distal side for inward direction becomes the sensory area with visual area at back of the head.

About numbers of things as numbers in a dimension chain:
5 different types of nerve cells are mentioned in cerebellum, while neocortex has a multitude: a relation few - many as between higher and lower degrees. (According to an old classification there were "about 50" different areas in cortex of cerebrum.)
   While cerebellum (like also inner cortex of cingulate gyrus in diencephalon as it seems) contains 3 cell layers, neocortex contains 6 layers, as number of "potentials" in a dimensions chain:

   Fig Ns-49-103-1

Certain of the dimensional aspects above on the nervous system seem possible to find in the 6 layers in cell columns of neocortex; here the layers renamed from outside inwards:

   Fig Ns-50-103-2

After Nf p. 256:

Fig Ns-51-103-3

00: Unspecific sensory impulses in; general anticenter, outermost layer.

0-4: Motor impulses = outward directed impulses out from innermost layers.

3: Sensory impulses in to layer 3 from 3 directions: specific sensory nerve pathways from the body, nerves from the (3-numbered) cerebellum and from pathways along the surface of cortex from associative areas. The cells can be regarded as interneurons and have effects on the pathways from layers 0 and 4 according to the reference.

1-2: In loop version of the dimension model we have that debranched degrees in higher steps outwards may meet the other way around as steps 2←1← 00:
   In layers 1-2 nerve fibers called collaterals could be apprehended as illustration: branches from outgoing motor axons, layer 0-4, go to layers 1-2.
   Then, from layers 1 and 2 perpendicular threads depart along the surface (note the angle step) to other columns in cortex and have the function of lateral inhibition. Cf. interpretation earlier of stimulation - inhibition as a polarity in step 2-1 in the chain of all polarities within the nervous system.

[ The order S - M in layers 3 - 2 may seem to conflict with the view on higher d-degrees as characterized of the 0-pole and outward direction in relation to the lower one but could be a result of a retained polarity from step 4 - 3 in the loop model.

Different types of sensory impulses are located to different columns. Hence, the qualitative differentiation is radial, while the divisions in locations are circular, i.e. which domains in the skin the signals come from.
   (According to a figure in reference Nf p. 236 one could ask if there eventually is a more fundamental division too between a group of sensory impulses from the skin senses and one from the inner milieu of the body, from joints, tendons and muscles etc.?)
   Conceptually the qualitative differentiation between different senses should represent different d-degree steps in the dimension model (cf. following files about senses).
   If such identifications are possible, how are the different qualities projected and arranged on the surface of different columns within a certain domain? (No data in the used references.) Consistently arranged in some way - perhaps in circles derived from different depths of levels as in the funnel figure here?

      Fig Ns-53-104-2

In motor cortex a certain area of columns represents direction of movements in a joint, regulated by a group of muscles, which get represented both vertically and horizontally (Nf p. 253). (Perhaps in the same way as in the funnel figure above?)

A principal outline of association areas as peripheral around more primary motor and sensory ones should with application of the funnel figure imply that the deeper the integration center, the wider the area for integration, the more complex the sensory impulses and reactions. In direction upwards in the figure, along the vertical axis, there would be more and more limited, elementary perceptions. Cf. "tunnel vision". (?)

In bundles of nerves the nerve fibers go increasingly peripherally, the further from the front end of the body they come from. This arrangement agrees with the fundamental identifications here of the front - back coordinate axis, derived from first A-V-axis animal-vegetative poles, 00 — 0.

         Fig Ns-54-104-3       Fig Ns-55-104-4

Compare the patterns of growth in bird embryos around the primitive streak and amoeboid movements through currents in the cytoplasm, right figure above.

Psychological "faculties":

We may associate the main parts of the brain with the psychological "faculties":
- will in the deeper sense of aim and direction with the brainstem;
- emotions with diencephalon and the limbic system;
- conceptions of the world as 3-2-dimensional structures and "plane" pictures with the forebrain including parts of diencephalon and inner "cortex of cingulate gyrus";
- thoughts as linear connections between concepts with neocortex;
- speech as thoughts transcribed into motions in last (and every) step:

Faculties - D-degrees - Brain parts:

   

Fig-Ns-56*

Note: step 1-0/00, some kind of communication and motor activity in each step.
   Potential "speech", "thoughts" and "concepts" should exist already in higher d-degrees and more elementary animals without a forebrain according to the loop version of the dimension model.

*See further a book in Psychology, "The I and the Ego" (not translated into English), connecting to these faculties and the general model. A description of the book in English here.