There are two primary forms of interconnection used in the neural system. They differ primarily in topography and can be considered convolutions of each other.
The simplest and most common is the simple in-line interconnection. This connection is used to connect one neural conduit to a second conduit. The connection is nominally symmetrical but need not be if the available space is a restriction. The most symmetrical form is that of the Node of Ranvier shown below in frame A. In this connection, the junction is located on the axis and the electrostenolytic processes are located in one or more collars surrounding the junction. The actual morphological structure of the neuron in this area is quite complex and difficult to image. It is not clear whether some of the sites of electrostenolysis are in direct contact with the surrounding medium or not.
The three frames of the figure are shown at very reduced resolution to accommodate a browser. Only in frame C is the external cell membrane shown as a bilayer. It should be shown in this form in all three frames if resolution allowed. The frames are shown at higher quality in Chapter 10 of the main work. Frame A shows the Activa as the vertical black rectangle at the center of the junction. It is supported by a group of electrostenolytic processess located in the longer rectangles arranged along the surfaces of the two conduits and on the bridging membrane between the two conduits. The bioenergetic materials supporting the electrostenolytic processes are shown entering the structure of the node and being stored in the metabolic reservoir labeled M as well as in the cross-hatched area adjacent to the surface of the conduits and membranes.
The dotted lines represent the currents going to and from the terminals of the Activa by way of the asymmetrical sections of the membranes involved. It is the summation in time of these three currents that are usually reported in the literature.
The simpler, and more prevalent in-line connection is that of the synapse shown in frame B. This more common form is also generally symmetrical but is shown here in an asymmetrical form merely to simplify the drawing. All of the critical functional elements are shown. The figure is shown at a higher magnification than in frame A. It shows some of the microtubules, neurofilaments and vesicles within the conduits. It also shows the components participating in the electrostenolytic process grouped in the upper part of the figure between the two conduits. The Activa of the junction is shown in the lower part of the figure between the conduits. The arrow represents the current path through the Activa. This topographic form may also be found in the so-called spherule type axon terminal of the photoreceptor cell.
It should be noted that a synapse can form whenever asymmetric sections of conduit membrane are brought to the appropriate spacing in an area supplied with the necessary metabolic fuels. The "growth process" involved appears quite simple. When the two surfaces are brought into the proper juxtaposition, two important phenomena occur. First, the spacing becomes so narrow that all large molecules are forced out of the junction by the rules of Brownian motion. Second, the remaining solvent, water, forms a liquid crystal of hydronium. The result is the formation of an Activa in this space that demonstrates "transistor action." Although it is only a suggestion worth exploring, such a new active site can be used to form a memory cell in the same manner as EPROMs (electrically programmable read only memories) are made by man. Two neurons in close proximity can easily form a latchable electronic memmory cell using this technique.
The convolution of the simple inline form is shown in frame C. The general topography shown has appeared frequently in the literature. The electrical overlay is presented here for the first time. This configuration is most commonly used when it is desired to interconnect one conduit with a large number of conduits such as in the case of the pedicel of the photoreceptor cell. The centerline position is now occupied by a electrostenolytic reservoir (marked M). This reservoir is marked by the horizontal stripping and extends into the narrow spaces analogous to the tributaries leading to a lake. The synapses between the photoreceptor cell and the two horizontal cells and the synapses between the horizontal cell and the bipolar cell are all located within these tributaries. This provides these junctions with access to the required metabolic supplies and electrolytically conductive paths associataed with the surrounding medium. The details associated with this figure are discussed in detail in Chapter 10 of this work.
As shown, the figure represents one pedicel, two horizontal cells and one bipolar cell. The central structure at the bottom of the frame is the dendrite of a bipolar cell. Other bipolar cell dendrites are shown passing near but not participating in the activities at this junction. The structure on the left labeled HD represents the dendrite of a horizontal cell. The structure on the right, consisting of the two areas labeled HP and HA, is a second horizontal cell.
The areas within the dashed lines are the electrolytically conductive reticulums of the various cells.
The functional performance of this network can be described in a few steps. All of the electrical waveforms found in the pedicel area are analog waveforms. The waveform associated with the photoreceptor cell is the generator waveform in the form it exhibits at the pedicel. The distribution Activa of the photoreceptor cell is shown and labeled the presynaptic Activa in this figure. The output signal of this device travels down the reticulum into the pedicel comples. The voltage signal is applied to both of the horizontal cells shown. The signal applied to the dendrite of the left horizontal cell exits the cell out of plane as shown by the small x. The signal applied to the poditic terminal, HP, of the right hand horizontal cell exits the pedicel area out of plane, is processed by the Activa within that horizontal cell, and returns to the area within the pedicel along the axon of the horizontal cell. This signal is passed to the bipolar cell dendrite via the synapse at the lower right of the figure. The signal then passes down the dendrite conduit to the Activa of the bipolar cell, labeled the post synaptic Active, for further processing or transmission.