A Series Of Statements
by Gerald Huth on September 11, 2005
I recall a reference to the effect that the outer segments of the retina should be viewed as an “almost crystalline array“. This captures the idea of this model..it is the precise (and exquisite!) geometric spacing of the array of receptor outer segments (or “nanowires”) that is effecting light interaction.
There also seems to be some evidence that the outer segments of individual receptors contain the ability along their length to dynamically alter their exact position relative to adjacent segments… somewhat like corn stalks moving together in a wind! I would like to hear more…
It occurs to me that I should add that the term”living” retina applies to the above comments… not the “dead, freeze dried” microscopic sections that vision science normally associates with a view of retinal receptors.
In fact, the term “living” must be associated with this entire model that relies entirely on structural order. I can imagine that the state of order implied in the model completely (and quickly) disappears at death.
One should realize the technological implications of this new model. The RGB filters of our cameras, CRT, LCD, plasma screens, and television pickup tubes only approximate what the eye achieves with exact geometric precision (a green mid-band filter used in the above devices is sensitive to an arbitrarily chosen wavelength near mid-band and, additionally, has a finite bandwidth). Moreover, retinal receptors detect and process narrowly tuned RGB brightness values i.e., a signal proportional to the density of the geometrically defined RGB antennas. Technology attempts to accomplish this at the source (i.e., remote to the eye) by sending three signals ) using “triad” or striped arrays of RGB filters in imaging displays. This model indicates with geometric logic exactly how and where on the retina these three RGB signals are received and “decoded”. The mechanism for synthesizing “color” in the eye seems to be exactly as Land deduced by obtaining the ratio of two brightness values on either side of the geometrically determined mid-band point.
I do not consider this work “a scientific hypothesis that must be experimentally verified, etc.”. Rather, as I have shown, in one stroke it actually explains the many experimental results that do not fit into the “traditional model” for vision and the eye (Wald’s finding of a “blue blind fovea” for example). It shows from first principles how the never explained, skewed distribution of cone and rod receptors on the retinal surface are directly correlated with (and follow from) the light refractive properties of the structure of the eye. It seems that the field initially correctly deduced the trichromatic nature of vision but then “picked the wrong model” and has ever since been attempting to “stuff all experimental results into it…” where they don’t fit… but they now do! Edwin Land correctly (and brilliantly!) deduced from external measurements the operation of the vision process but the only model that he had available for the inner workings of the eye was the tradtional one that wrongly conceived the organ as a “camera.”
It is apparent to me that the field of vision science with it’s view of the eye as the analogue of a “camera” quite some time ago reached a dead end. This new view of the vision process, in addition to logically explaining experimental results obtained over the years that have appeared irrational, is predictive as it must be if it to have any validity.
Some examples (I will term these short range predictions… longer range will follow):
- Careful computer simulation of light refraction within the eye will show an exact correlation with the geometric response of retinal receptors proposed in this model (the “Rosetta Stone”). This is already evident, but unrealized, in the magnitude of longitudinal chromatic aberration of the eye.
- The model elicits the first principles leading to the condition of macular degeneration, namely, that the diameter of rod receptors (which sets inter receptor spacing) in defining the short wavelength limit of vision controls the entrance of biologically damaging ultraviolet light into the eye ultimately leading to this degenerative condition.
- Genetic expression of retinal receptors will be found to effect the structural dimensions (i.e., diameter) of the inner, space defining, segment of receptors.
- A review of George Wald’s experimental efforts will show how well they correlate with this model. I have in mind his finding of a “blue blind” fovea, his discovery of only one retinal “pigment” (when he thought, using the traditional model, that here must be three), and his description of the wavelength sensitivity of the retina in his Nobel lecture that, in fact, closely agrees with this geometrically deduced model.
- Assuming that the geometrically defined receptor appositions of this model define the short and long wavelength limits and the exact angle to which mid-band (~550 nm) is refracted, many correlations will be made. Pupillary constriction will be shown to be controlled by the short wavelength limit – the corollary of which is that the rods of the peripheral retina will be shown (if they have not already been) to be connected in parallel effecting the “light meter” that I have proposed.
It will be shown that brightnesses at the three primary wavelengths detected by the retina , and ratioed on either side of the geometrically determined mid-band point will verify the mechanism of vision propose by Edwin Land. In fact, Land’s theory and simulations made external to the eye will be found to be directly transposable to computational mechanisms operative within the biological substructure of the retina of the eye.
- And many more… to be added
A Series Of Statements
by Gerald Huth on September 11, 2005
I recall a reference to the effect that the outer segments of the retina should be viewed as an “almost crystalline array“. This captures the idea of this model..it is the precise (and exquisite!) geometric spacing of the array of receptor outer segments (or “nanowires”) that is effecting light interaction.
There also seems to be some evidence that the outer segments of individual receptors contain the ability along their length to dynamically alter their exact position relative to adjacent segments… somewhat like corn stalks moving together in a wind! I would like to hear more…
It occurs to me that I should add that the term”living” retina applies to the above comments… not the “dead, freeze dried” microscopic sections that vision science normally associates with a view of retinal receptors.
In fact, the term “living” must be associated with this entire model that relies entirely on structural order. I can imagine that the state of order implied in the model completely (and quickly) disappears at death.
One should realize the technological implications of this new model. The RGB filters of our cameras, CRT, LCD, plasma screens, and television pickup tubes only approximate what the eye achieves with exact geometric precision (a green mid-band filter used in the above devices is sensitive to an arbitrarily chosen wavelength near mid-band and, additionally, has a finite bandwidth). Moreover, retinal receptors detect and process narrowly tuned RGB brightness values i.e., a signal proportional to the density of the geometrically defined RGB antennas. Technology attempts to accomplish this at the source (i.e., remote to the eye) by sending three signals ) using “triad” or striped arrays of RGB filters in imaging displays. This model indicates with geometric logic exactly how and where on the retina these three RGB signals are received and “decoded”. The mechanism for synthesizing “color” in the eye seems to be exactly as Land deduced by obtaining the ratio of two brightness values on either side of the geometrically determined mid-band point.
I do not consider this work “a scientific hypothesis that must be experimentally verified, etc.”. Rather, as I have shown, in one stroke it actually explains the many experimental results that do not fit into the “traditional model” for vision and the eye (Wald’s finding of a “blue blind fovea” for example). It shows from first principles how the never explained, skewed distribution of cone and rod receptors on the retinal surface are directly correlated with (and follow from) the light refractive properties of the structure of the eye. It seems that the field initially correctly deduced the trichromatic nature of vision but then “picked the wrong model” and has ever since been attempting to “stuff all experimental results into it…” where they don’t fit… but they now do! Edwin Land correctly (and brilliantly!) deduced from external measurements the operation of the vision process but the only model that he had available for the inner workings of the eye was the tradtional one that wrongly conceived the organ as a “camera.”
It is apparent to me that the field of vision science with it’s view of the eye as the analogue of a “camera” quite some time ago reached a dead end. This new view of the vision process, in addition to logically explaining experimental results obtained over the years that have appeared irrational, is predictive as it must be if it to have any validity.
Some examples (I will term these short range predictions… longer range will follow):
It will be shown that brightnesses at the three primary wavelengths detected by the retina , and ratioed on either side of the geometrically determined mid-band point will verify the mechanism of vision propose by Edwin Land. In fact, Land’s theory and simulations made external to the eye will be found to be directly transposable to computational mechanisms operative within the biological substructure of the retina of the eye.