New Chromaticity Diagram

MAJOR THEMES OF THIS WORK
PROCESSES IN BIOLOGICAL VISION



Last Update 02 July 09         Rhodonine™ and Activa™: See Citation Page

This work differs fundamentally from the conventional wisdom concerning Vision.   Many of these variances are summarized on this page.

The most important differences are summarized in the following sections:

PARADIGM SHIFTS SUPPORTING THE THEORY

One of the primary reasons for preparing this text, which grew beyond all expectations, was to provide a sufficiently broad base to successfully challenge the conventional wisdom that photoexcitation in vision involved the process of isomerization. As described, that process has always required energy from a distinct source separate from the incident photons. There was another mechanism that was clearly more appropriate.

There was a similar problem in the area of how the above photoexcitation process led to an electrical signal within the neural system. Exploration led to a rational solution to this problem. That explanation led to a more complete understanding of how the generated signal was transmitted to the brain, etc.

The following basic principles were defined based on the available laboratory investigations. They are in blatant conflict with the conventional wisdom. However, they do provide the most comprehensive explanation of any available theory of vision. This explanation extends to levels of detail that are not even discussed in alternate theories.

It is hoped that these basic principles can be kept in mind as the reader explores this site and the printed text. It is hoped that the reader will discern the value of these proposals when he/she examines the added insights they provide into the visual system in man and other animals.

I.  Vision is basically tetrachromatic, not trichromatic

An astounding finding of this investigation was the fact that the basic architecture of biological vision is tetrachromatic. In the fully developed visual system, four chromophores are used to support four spectral channels. These channels are in the ultraviolet, blue, green and red. There has been a growing awareness for some time that many chordates exhibited tetrachromatic vision. During the last quarter of the 20th Century, it was shown that the retina and later parts of the human visual system are tetrachromatically organized. The human visual system is limited by the lens group of the eye. This property is shared with other large animals. As a result, these animals are fundamentally blocked tetrachromats instead of trichromats. This fact is important when exploring the short wavelength capabilities of the visual system (and when attempting to correlate genetic code to vision).

II.  Rhodonine instead of Rhodopsin

The experimental literature is now conclusive that rhodopsin is not formed within the photoreceptor cells. The photoreceptor cells are known to secrete opsin that is then extruded to form the disks found in the Outer Segment associated with each cell. The opsin is then coated with a chromophore in liquid crystalline form that is created within the retinal pigment epithelium layer of the retina.

It is proposed that this liquid crystalline material, known as Rhodonine®, is the chromophore of vision. This material is fabricated from retinol by a well defined series of processes. Rhodonine is a close relative of the chromophores used in color photography. It is excited by a quantum mechanical process exactly as in color photography and is de-excited by a well known process (used commonly in solid state transistors) occurring at the dendrites of the photoreceptor cell. No external source of quantum level energy is required. This excitation/de-excitation process precisely describes the "waveform generator" signal reported in the literature.

Rhodonine is found in four varieties, all of which are used in vision. Using the proper technique, any one of the four variants of the material can be extracted from a retina and reconstituted in the laboratory. (This experimental sequence has never been performed with the putative rhodopsin)[5.5]. The recovered material exhibits precisely, and without difficulty, one of the four spectrums found in vision. The actual operational spectrum of the putative rhodopsin has never been recorded in-vitro in the laboratory.

III.  The neuron as an electrolytic semiconductor device

Conventional wisdom since the 1950's has been that the axolemma of the neuron, a simple bilayer film of liquid crystalline triglyceride material, is an active two terminal device. There has been no explanation of why it is active. As an alternative explanation, it is proposed that when two such bilayer films are brought into close proximity, the resulting structure can form a three terminal electrolytic semiconductor device, known as an Activa®. This device acts like a conventional solid-state semiconductor device. The Activa is an electrolytic, (organic) semiconductor device, US Patent #5,946,185. Such a device can be found at every junction between two plasmolemmas in the nervous system. The three terminal Activa is the fundamental building block of the nervous system and accounts for the detailed performance of the synapses, the Nodes of Ranvier, and both the de-excitation of the chromophores of vision and the adaptation process. [8]

IV.  Replacement of the constant field equation of Goldman

With the introduction of semiconductor theory to explain the fundamental character of the biological membrane at the molecular level, the constant field theory that has evolved based on Nernst, Donnan & Goldman is found to be inadequate. The potential barrier found within the relative portions of the plasma membrane of a neuron introduces a variation in the potential field within the membrane that profoundly impacts the permeability of that membrane. The state of a neural conduit is best explained by a new variable field theory.

V.  The eye as a change detector, not an imager

Because of conceptual simplicity, conventional pedagogy teaches that the eye is an analog of the simple box camera (with a simple lens system) and the retina acts like a piece of photographic film. Unfortunately, the overwhelming evidence that the eye is not an imaging device is not introduced at higher levels in the educational system. Volumes have been written on the fact that the human eye is blind in the absence of motion between the optical line of sight and the scene. This motion is normally provided by the tremor associated with the ocular globe of the eye.

It is proposed that the photoreceptor cell is a change detector and not an imaging element. Recognition of this well documented situation leads to a detailed explanation of the adaptation process and color constancy, as well as many special optical illusions.

Vi.  The specific definition of color at the fundamental level

In the absence of a precise definition of color in the conventional wisdom, a paradigm shift may be an inappropriate description for this section. However, it is necessary to define a color uniquely from a conceptual, scientific and practical perspective.

A perceived color for a long wavelength trichromat is defined precisely by the pair of values, (P,Q), associated with the two chrominance channels of animal vision. These are best visuallized via the New Chromaticity Diagram for Research. This Diagram demonstrates the bilateral orthogonality of the visual system, a P-channel and a Q-channel, as opposed to the long assumed trilateral symmetry, RGB or xyz, of the system.
The individual is taught, within his cultural and semantic environment, to associate a name to each set of perceived P,Q values. The values describe the precise color perceived. The semantic name is that used to report the perception of that color by the individual.

Based on the above definition, the precise definition of white is also available.

"White is the reported color, of a light or an illuminated surface, perceived by an animal when each and all of the chrominance channels of its visual system are reporting a null condition to the cortex for that incident illumination. For a long wavelength trichromat, this condition corresponds to a null in both of the chrominance channels, P:Q::0:0"

The above definition leads to one additional definition required to avoid controversy. For completeness, it has been divided into two variants.

Neglecting the effect of the illumination for a moment.

Any two surfaces that cause the same (P,Q) values to be perceived and interpreted by the cortex when illuminated by the same source, are defined as metamers in object color space.

For completeness, a broader definition can also be given.

Any two surfaces that cause the same (P,Q) values to be perceived and interpreted by the cortex when illuminated by different sources, are defined as trans-metamers in object color space.

PREMISES DEVELOPED IN THIS WORK

To aid in understanding this work, it is useful to provide a roadmap of the premises developed within it. It is only by comprehending these premises as a group that the overall work can be considered and the scope of the entire work can be appreciated.

An attempt will be made to list these premises in a quasi hierarchal manner beginning in object space and proceeding toward the cortex. However, the system deviates substantially from a single topological signaling path, or even parallel topological paths. The bold roman numerals, e.g. (II), at the start of a subject indicates it is directly related to the above section on PARADIGM SHIFTS

These premises were developed in conjunction with the development of the various block and circuit diagrams of vision and are based on the data in the literature. The premises are confirmed by the ability of a new set of performance descriptors to define the performance of the visual system with a precision not found elsewhere. All of these performance descriptors can be filtered to emulate the performance previously measured in the laboratory with less than adequate instrumentation or experimental design. Many of these premises can be confirmed by the reader, in an anecdotal manner, using the simple tests defined at this web site.

Basic Premises

  1. A phylogenic tree of the animal kingdom can be presented that allows the visual system of Arthropoda, Mollusca and Chordata to be traced back to a common ancestor.

  2. The thickness of the physiological optical system forward of the retina plays a major role in determining the spectral capability of an animal.

  3. The photoreceptors of vision are quantum, as opposed to energy, detectors.

  4. Photoexcitation and de-excitation are quantum mechanical processes

  5. (I) Spectral absorption is accomplished in the Rhodonines, a resonant form of the retinoids while they are in the liquid crystalline state.

  6. The Outer Segment of a photoreceptor cell is NOT an integral part of the cell

  7. Translation of the signal from the disks of the Outer Segment to the dendrites of the photoreceptor neuron is a piezo-electric process.

  8. (II) The fundamental neural mechanism involves an active electrolytic semiconductor device, the Activa,

  9. The neural system is fundamentally electrolytic in operation.

  10. There is no functional equivalent of the morphological distinction, "rods and cones," in the animal visual system

  11. The first of two Activa within each photoreceptor cell is used to form the adaptation amplifier of each spectral absorption channel.

  12. The transient performance of the adaptation amplifiers is due to both the excitation (bleaching) of the chromophore material and the limited metabolic supply phenomena.

  13. (III) In order to accomodate the extreme range of radiant intensity in the natural environment within the limited dynamic range of the perceptual signaling channels, the adaptation amplifier effectively removes the average component of the signal representing the radiation incident on a given photoreceptor cell.

  14. The second Activa found within each photoreceptor cell operates as a grounded base amplifier with an input terminal, emitter, connected with the emitter of the adaptation amplifier within the same cell.

  15. Following logarithmic conversion at the pedicels of the photoreceptor cells, separate signaling matrices are created using lateral cells to create the primary perceptual signals used in the visual process. These matrices are of two types, those using horizontal cells to create the luminance, chrominance, and polarization signals and those using amercine cells to create the appearance signals.

  16. The signal processing related to the photoreceptor cells of the foveola is fundamentally different from the ex-foveola cells. These signals are treated uniquely.

  17. The employment of separate luminance and chrominance signaling channels, employing distinctly different mathematical manipulations, is not compatible with a "linear vision model" except under the most restrictive small signal conditions. In addition, it is clear that the chrominance signaling channels of vision do not employ "additive color" principles.

  18. (IV) By plotting the relative value of the voltage representing P and Q compared to their quiescent value in the visual system of the long wavelength trichromats, it is possible to obtain a definitive New Chromaticity Diagram for Research.

  19. The signal projection system of chordates employs a very sophisticated spatial and temporal encoding system to minimize the mechanical stiffness associated with the optic nerve.
  20. The system employs a "matched pair" of time dispersion filters, mechanical topographic structures, to allow stereoptic and other spatial signals to be processed in the time domain without disturbing the overall operation of the system with respect to the cortex.

  21. The vast majority of the neurons in a given animal are operated in the analog mode.

  22. The fundamental mechanism displayed by a neuron is not the excitability of the axolemma. It is the "excitability, i. e. transistor action" achieved at the junction between two lemmas.

  23. The so-called voltage clamp configuration has not been well characterized in the past. The circuit diagrams of this work, reachable from the Navigation Bar, illustrate at least five fundamentally different operating states obtainable by implementing the standard voltage clamp protocol.

  24. There are three fundamental types of electrolytic circuits within the neural system

  25. The operation of the projection neurons of the neural system (such as the ganglion cells of the retina) are poorly understood.

  26. The literature has not clarified the high rate of signal manipulation possible within the neural system

  27. The literature has not yet defined the organizational architecture of the cortex, at least of the primates.

  28. The neural system of animals achieves extremely high efficiency through the use of completely reversable electrolytic and electrostenolytic processes, the use of diodes as sources of resistivity, but not resistance, and operation at very low current densities.

  29. There is considerable danger in attributing color defects in the visual system to specific genetic factors due to the large variety of failure modes within the visual system. It is very unlikely that all of the failure modes relatable to a single clinical condition can be assigned to a malfunction of only a single gene.

FUNDAMENTAL CONCLUSIONS

I.  Maxwell & Hering were both right

By examining the visual system, in sufficient electrophysiological detail, it becomes clear that Maxwellian Theory plays a dominant role in the achromatic operation and Hering Theory plays a dominant role in the chromatic operation of the visual system. The development of a detailed model of the process shows that the debate that has been running for over 100 years is based on apples and oranges.

Abney and later Grassman were wrong with respect to vision

The field of Photometry has developed based primarily on the assumption of additive color mixing of lights. Only with the advent of color reproduction via printing has subtractive color mixing through the use of pigments become important. Abney and later Grassman codified the laws of additive color, including the assumption of linearity, as they apply to lights and used those properties to describe vision. By examining the visual process, it becomes abundantly clear that the laws of vision are not based on additive color mixing. The so-called Basic Equation of Photometry does not apply to the perception of brightness. It applies only to the luminosity of a scene.

II.  Color, as a phenomena, can be defined rigorously

There is no widely recognized, detailed definition of color in the literature. The reason appears related to the number of different situations where the phenomena arises. By subdividing these situations into eight cases, a definition of the phenomena of color can be given for each one. The most important cases involve light emanating from a source, sometimes called aperture light, light reflected from a surface, sometimes called, surface light, and the electrical signals resulting from the detection of light by the photoreceptor cells, and known in this work as perceived light. The perceived light is processed in two distinct signaling channels, the luminance channel and the chrominance channel. The light in the chromimance channel can be properly defined as perceived color.

The important fact is that the spectral properties of aperture light are additive as a function of wavelength, the spectral changes brought about by reflection or absorption by a non-radiative medium are subtractive as a function of wavelength, and the spectral properties of perceived light are manifest in two orthogonal bipolar voltages obtained by a discreet subtraction process between pairs of signals of different spectral origin in the photoreceptor cells.

Because of the subtractive nature of the perceived color signals, the fundamental assumption concerning additive colorimetry and the entire C.I.E. structure of Color Standards is inappropriate for precisely describing the visual process.

III.  The New Chromaticity Diagram can be combined with the Munsell Color System

By overlaying the Munsell Color System on the New Chromaticity Diagram for Research, it is possible to assign unique absolute spectral wavelength components to any color sample based on a New Combined Chromaticity Diagram. This three dimensional diagram is named The Sensation Space of Human Vision.

It is possible to increase the precison and accuracy of the Munsell System using this new Sensation Space as a tool. The samples must be observed under the illumination conditions specified in the original Munsell protocols,which are the same as those called for by the ICSS-NBS publication of 1955 (and reprined in 1976-77). These protocols call for daylight illumination using a northern exposure (no direct solar illumination), essentially corresponding to an equal quantum flux illuminant at 7053 Kelvin as defined in this work. Within this work, this illuminant is defined as Illuminant F or D70.

The above ICSS-NBS publication listed 267 specific color names to describe the complete Munsell Color Space. There was no suggestion of a correlation between any of these names and spectral wavelength. Using the above overlay method, specific spectral attributes can be assigned to each of these names, subject to an agreement on how to determine the centroid of the color space assigned a specific name.

This assignment method assigns the same spectral wavelengths to metamers since the assignment is based on the median spectral content of the sample in each of two spectral bands, as represented by the P and Q channels in perceptual space. If desired, auxiliary spectral filters can be used to determine individual secondary spectral wavelength designations for individual metamers.

FINDINGS RELATED TO THE NEURAL SYSTEM

I. The neural system is electolytically rather than chemically based.

The neural system consists of a series of electrolytic conduits separated by Activas, active electrolytic semiconductor devices similar to transistors.

The equilibrium laws of Nernst, Donnan, Goldman and Hodgkin & Huxley do not apply to neurons.

Based on the knowledge gained since the 1950's, it is clear that the biological bilayer membrane used to form the neural conduits is not permeable to ions. These membranes can be symmetrical at the molecular level in which case they are also impermeable to fundamental electrical charges. If they are asymmetrical at the molecular level, they remain impermeable to ions but are electrically asymmetrical and semiconductive to fundamental charged particles (electrons and holes).

The asymmetry of the biological bilayer membrane to electrons is clear proof of the existance of a variable electrical field within the membrane. Such a field is inconsistent with the fundamental assumption of a constant electrical field used in the derivation of the Nernst, Donnan, Goldman and Hodgkin & Huxley equilibrium equations.

II. The argument over a chemical versus electronic synapse is over

The vast majority, if not all, synapses are fundamentally electrolytic and contain an Activa.

The electrolytic hypothesis provides detailed answers to questions about the synapse. These same questions can not even be expressed under the chemical hypothesis.

FINDINGS RELATED TO THE CORTEX AND MID-BRAIN

Great strides are being made at this time in our understanding of the brain. Only particularly relevant comments will be made here.

I.  The organization of the brain is not linear or sequential

Literature of the late 20th Century has been showing the topology of the cortex of the brain related to vision as essentially linear or consisting of two parallel linear paths with crossover connections. In both cases, entry to the visual part of the brain was via the "primary visual cortex," labeled V1. This is inappropriate.

Entry points

There are two primary entry points to the cortex for visual signals. Signals from the lateral geniculate nuclei of the thalmus enter the cortex via the "coarse imagery" visual center, labeled V1 or area 17.

Signals from the Precision Optical System associated with the tectum enter the cortex via the precision imagery visual center, located within area 7.

Organization

The cortex consists of an essentially two dimensional laminate of about six layers in thickness. Each small region of the two dimensional surface consists of functional sites defined as engines in this work. These engines are interconnected in a n-pointed star configuration that allows efficient interconnection between any two nodes of the star network. The engines associated with a given function tend to be located within a specific area. The location and inter-relation of the various areas appears to have been chosen on architectural and signal handling grounds.

II.  The signal processing within the brain is concentrated in a large number of processing engines

The signal processing function within the cortex appears to be concentrated in an uncountable number of individual signal processing engines. Most of the engines related to vision can be described as extraction engines that implement various extraction mechanisms (or signal processing routines). Additional engines, particularly in the frontal lobe of the brain can be considered cognitive engines implementing other routines. Engines along the intersection of the frontal lobe and occipital lobe appear to be primarily involved in the generation of neural signals to control the body. They can be considered implementation engines.

III.  The bandwidth of the signal paths within an engine are very high

The bandwidth of the majority of the skeletal and sensory nervous system is apparently limited by the tradeoff between signal bandwidth and signal transmission velocity with the instantaneous availability of electrical power as a parameter.

The bandwidth of the neural paths within the individual engines of the cortex, and possibly other portions of the brain are not limited by the above constraint (although inter-communications paths are).

Because of the extremely short signal paths found within a given engine, the limiting signal bandwidth of a circuit can be very high. This allows the signal processing within an engine to proceed at a much higher, and asynchronous, rate than in the peripheral and interconnecting nervous system. Although not quantified to date, the noise spectrum associated with the background obtained when recording signals from the cortex suggest the maximum rate may be on the order of a megahertz or higher.

FINDINGS RELATED TO READING

While many of the chordates,and a few molluscs (squid, etc.) are able to recognize relatively abstract features of objects, such as recognizing objects of different color, and to some extent different shape, even the other primates are not able to perceive the differences between intricately drawn shapes. This unique human capability has allowed the development of communications through writing and printing.

This unique capability has developed in the human through the more advanced evolution of a special analytical channel of vision that lower species have not achieved. This analytical channel is distinctly separate from that studied heretofor. It does not involve the primary visual cortex or the Lateral Geniculate Nuclei of the visual system. These major engines of vision are primarily concerned with the awareness of the environment surrounding the individual.

The unique abilities associated with reading and other procedures involved in the recognition and interpretation of fine spatial detail use a separate visual pathway known as the analytical channel. This channel originates in the very center of the fovea, the foveola, and proceeds to the Precision Optical System (POS) of the midbrain along a distinctly different neural channel than the rest of the information from the retina. The retina and POS combine with the oculomotor subsystem to form a high performance servomechanism (feedback loop) that is critical to the analytical process.

The pretectum of the POS is the key engine of the analytical channel. It both controls the operation of the eye muscles and extracts information from the image projected onto the foveola. It then transmits the information, in vectorial form, directly to area 7 of the cortex via the Pulvinar Pathway. The data does not pass by way of the principal visual cortex in area 17-19.

Area 7 of the cortex plays two roles. Its older role, shared with other animals, is to interpret the awareness information presented to it in vector form from areas 17-22 of the cortex. Its newer role, relative to evolution, is to perform the same functions at a more precise level using the more precise, and timely, information received from the pretectum.

The feature extraction engines of area 7 use the results of their interpretation for two purposes. Critical data, regarding the safety of the animal, is transmitted back to the midbrain, primarily the superior colliculus, in a reflexive mode designed to cause the animal to take evasive or aggressive action. All data is also passed to a saliency map that maintains a perception, using all sensory inputs, of the environment surrounding the animal. This saliency map is the foundation of the memory system.

The information passed to area 7 from both the pretectum and via areas 17-22 is vectorial in nature, involving concepts derived from the context and syntax of the information in the visual field of view.

The pretectum has a major task associated with the extraction of this vectorial information from the image projected onto the foveola. It accomplishes this task by scanning the image using a scan pattern it generates and generally defined as involving the tremor of the eyes. Tremor is a term describing the very fine, virtually continual, vertical and horizontal motion of the eyes. Each component of the tremor is typically less than 40 seconds of arc in amplitude and contains frequency components up to about 150 Hz. These motions are not clinically observable without special instrumentation. They are the key to the operation of the analytical channel and READING.

The reason these precision analytical tasks are performed in the pretectum is to minimize the time delay in signals passing around the servo loops of the POS. If they were performed in the cortex, the additional delay would reduce the reading speed of a typical individual by a factor of three.

(for more detail, go to the reading home page)