Rethinking the Process of Vision

I am often asked what medical or other benefits might follow from my explanation of the vision process? I have pointed to a number of such areas as they have occurred to me but it certainly seems that any fundamentally new understanding must inevitably lead to new “take off points” in our broader view of, and, perhaps more importantly, what lies beyond, what we understand as vision.

Examples of possible medical benefits:

a.) Although medical literature generalizes that exposure to ultraviolet (UV) radiation somehow leads to the condition termed ‘age-related macular degeneration’ (or AMD) no direct physical linkage is presented. I am sure that the physics-minded would understand a general connection of the higher energy of ultraviolet light with damage to biological structures, however, this is still only a generalized statement. It is apparent that the retina can sustain damage over the years that it takes AMD to develop and in this regard there is progress in vitamin, mineral nutrient supplements that I would guess aid in UV-induced damage repair. It has even been reported that the ‘gene related to AMD has been found’…but this is beyond me! This model provides an understanding that the size of rods comprising the peripheral retina actually defines the short wavelength limit of visual response and, concurrently, controls constriction of the pupil of the eye and thus overall light entrance into the eye at short wavelengths adjacent to the damaging UV region. It is my premise that this is the “first cause” of the AMD condition. Although saying nothing about the “disease” termed AMD it certainly substantiates efforts aimed at advising the population to avoid UV exposure even in their younger years. Somewhat tongue-in-cheek, if one wants to involve genetics, one should set out to genetically modify the diameter of rod receptors (by increasing the diameter of their inner segments) to increase inter receptor distance thus moving the short wavelength limit of vision away from the biologically damaging UV region!

b.) A number of research projects are currently underway around the world aimed at fabricating an ‘artificial retina’ silicon chip to aid the sightless. These efforts as far as I can determine assume that the retina is the intensity-only-sensitive image plane of the optics of the eye and therefore employ in some form the technology developed for camera imaging, i.e., charge-coupled devices etc. This work proposes that the retina is actually the Fourier or focal plane of the eye and thus is responsive not only to light intensity but also to light phase (that encodes direction of incoming light). This implies that a Fourier transforming, and not an intensity-only-sensitive, camera-like process is operative in forming the visual image. An entirely new light is therefore shown on these developmental efforts and I believe an insight is available whereby it may be possible to actually reproduce the biological retina. This is technical…but… I propose that the new technology of “porous silicon” surfaces might be used to fabricate such devices as it is possible to visualize that such surfaces might conceivably be configured to form visible light detection surfaces capable of simultaneously detecting both intensity and phase.

c.) “Color blindness”. This new view defines an entirely different mechanism as the cause of this condition. I propose that it is not the ‘absence of a certain class of cones’ as generally proposed, but rather the result of an alteration (genetically induced) in the ratio of the size of cone to rod receptors with the result that the fundamental, geometrically-determined mid-band wavelength reference point is shifted in wavelength and concurrently moved from it’s normal location at 7-8 degrees of retinal angle (I assume that the refractive properties of the lens and body of the eye do not change). Land demonstrated in his work that even a slight shift in the location of this wavelength greatly altered the perception of color. Again, if one wanted to “correct” this condition the path (for future generations) would be to genetically alter or control the diameter of either cone or rod receptors (their inner segments).

Examples of new physics-based concepts that might follow from the concept:

a.) I greatly admire the thoughts of Julian Barbour (“The End of Time – The Next Revolution in Physics”, Oxford University Press) questioning the concept of time itself and replacing it conceptually with an existence based on probability. The sheer breadth of the idea seems at once to solve the great historical conundrums of physics. In the context of my idea, it is a property of the Fourier plane of a condensing lens (the location of the retina as I propose) to bring light from all points of an extended image into time coincidence at this point. I can imagine ‘time coincidence’ as the negation of time. The image on the retina it seems to me is the only place where such ‘timeless’ negation occurs (I must note that the only location of a ‘pure’ Fourier transform on the retina is at the fovea and results solely from long wavelength, i.e., red, interactions). From my window ..I see light reflected from a host of varying distances (and thus times) …I see light reflected from distant mountains that left those points on the image microseconds ago and light reflected from my computer monitor that was reflected nanoseconds ago….and yet each point of light is brought into a state of ‘zero time” on my retina! Is the “instant of time” determined on my retina? Meaning?

b.) I have written elsewhere in this work about the possibility (I actually believe, probablility) that the optical “antenna” detection structures (receptor appositions) of the retina possess the capability for radiating a light signal back into the environment. It is a well understood and fundamental property of antennas that they are able to radiate electromagnetic signals as well as receive them. I have proposed even further that the Fourier plane of the retina acts as a ‘phase conjugate mirror’ that would radiate such signals back along the exact path upon which they entered the eye. If this picture were true it would question the historic role ascribed to the eye as a passive optical receiver. I have ascribed a physical ‘connectedness to external reality’ to this two-way passage of light and see some possible relation to consciousness ..at least via the visual pathway.
Meaning?

A bit of relevant text from Erwin Schrodinger’s Mind and Matter”

“I wonder has it ever been noted that the eye is the only sense organ whose purely receptor character we fail to recognize in naive thought. Reversing the actual state of affairs, we are much more inclined to think of ‘rays of vision’ issuing from the eye, than of the ‘rays of light’ that hit the eyes from outside. You quite frequently find such a ‘ray of vision’ represented in a drawing in a comic paper, or even in some older schematic sketch intended to illustrate an optic instrument or law, a dotted line emerging from the eye and pointing to the object, the direction being indicated by an arrowhead at the far end. - Dear reader, or better still, dear lady reader, recall the bright joyful eyes with which your child beams upon you when you bring him a new toy, and then let a physicist tell you that in reality nothing emerges from those eyes; in reality their only objectively detectable function is, continually to be hit by and receive light quanta. In reality! A strange reality! Something seems to be missing in it.”

And later on in a discussion of a quantum physics description of ’subject and object’ as proposed by Bohr, Heisenberg, and Born:

“We cannot make any factual statement about a given natural object (or physical system) without ‘getting in touch’ with it. This ‘touch’ is a real physical interaction……..”

More thoughts as they occur.

GCH

Added March 19, 2006

I reiterate my earlier Comment proposing that measurement of the wavelength sensitivity of ‘retinal mosaics’, made by Rooda & Williams at a retinal angle of one degree, be made at larger retinal angles. I predict that such measurements will show an increasing density of green ‘cones’ with increasing retinal angle reaching a maximum density (i.e., all green response) at 7-8 degrees. These green sensitive centers will not (could not because there are very few cones here) correspond to cone response but rather to cone-rod appositions which reach a maximum at that angle.
GCH

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I had proposed in my original paper that the figures in the paper by Roorda / Williams (Nature, Vol.397, pp 520-522, 11 February 1999) portrayed regions somewhere beyond the one degree retinal angle claimed by the authors. This was based on the presence of regions of green and blue sensitivity (their Figure 3). The authors claimed that these were due to the presence of green and blue sensitive cone receptors and that the views represented the configuration of these different species of cones at one degree of retinal angle. .
I now believe that I misspoke and that the views did represent the distribution of color detection centers at this angle but that these are not due to the response of cones but rather seem consistent with my hypothesis. I also believe that the rather heroic imaging methodology used in these measurements probably portrays an accurate picture of the distribution of such centers and that it may be used to validate my model.
The authors state that their measurements were made at a retinal angle of one degree and that all of the color centers are cones and that therefore no rod receptors appear in the views. However, Wald in Figure 9 below taken from his paper (“Blue-Blindness in the Normal Fovea”, Jour. Opt. Soc. Am, Vol. 57, No.11, November 1967) recounting Osterberg’s data notes that at one degree the density of cones and rods is approximately equal at 40,000 per sq. mm. Now, I will grant that at this angle cone and rod receptor densities are falling and rising precipitously introducing the possibility of error in measurements made in this region. However, I believe a more logical explanation is that the measurements are accurate and are explained by my model.

At one degree of retinal angle, and as I have said previously, the smaller rod receptors are beginning to “intrude” in a statistical manner into the hexagonally ordered (and tight packed) array of larger cones (remember that although the densities of the two receptors are about equal the cones are almost twice as large as rods). Therefore, a statistical distribution of rod-cone appositions is observed (Osterberg) that I would claim form the green centers observed by R/W. As rod density rapidly increases a statistically smaller number of rod-rod appositions is present (again, see Osterberg’s figures) that I would claim correspond to the fewer blue sensitive centers in this region.
I have proposed that if R/W would extend their measurements to retinal angles beyond one degree they would observe an increasing number of green sensitive centers until at 7-8 degrees the field would be totally green, i.e., rod density is sufficient to completely surround each cone at this point presenting a field of green detection centers.

GCH

The following is another bit of abstracted text from Arthur Koestler’s “Ghost in the Machine”, pp168-169:

“………The revolutions in science are successful escapes from blind alleys. The evolution of knowledge is continuous only during those periods of consolidation and elaboration which follow a major break-through. Sooner or later, however, consolidation leads to increasing rigidity, orthodoxy, and so into the dead end of overspecialization. – to the koala bear. Eventually there is a crisis and a new ‘break-through’ out of the blind alley – followed by another period of consolidation, a new orthodoxy, and so the cycle starts again.

But the new theoretical structure which emerges from the break-through is not built on top of the previous edifice; it branches out from the point where progress has gone wrong……….”

GCH

You open your eyes in your dark bedroom at night. All that you see are colorless outlines of doors, windows, edges, etc. – the image is completely devoid of the sensation of color. Textbooks on vision tell you that under this circumstance the ‘black and white-sensitive’ system of rod receptors with its purported higher sensitivity to light has taken over from the less sensitive color detecting cone system. Did it ever occur to ask: what is the basis for this statement? I remember a statement from a recognized vision science researcher that “no one believes this anymore”! The question that follows is: how is the image from either one of these cone and rod “systems” actually formed on the retina? This consideration is never discussed but it is just concluded that the eye is a kind of “camera” and the retina a direct analogue of a kind of photographic film. Textbooks are replete with “inverted arrow” diagrams indicating this. Such a retina would require that the cones and rods were arrayed in some sort of logically ordered mosaic. However, a perusal of measured receptor density data shows a wildly asymmetric distribution of cones and rods. Most (>99% ) of the cones are found in a very small central area of the retina encompassing less than one degree of retinal angle (the fovea). The preponderance of rods are located in the peripheral retina at angles generally greater than 10-20 degrees. Moreover, rods and cones are found to be statistically distributed across the retinal surface. What is one to make of this?

How can one persist in believing these statements found in textbooks used daily by students? How did one arrive at the notion that cones detect color (and that they have reduced sensitivity to light), and that rods detect black and white (with high sensitivity)? I propose that these statements are totally false!

My explanation follows directly and exactly from the measured asymmetric distribution of receptors. I conclude that what one is seeing in that dark bedroom is an image formed solely on the all-cone fovea from the long (red) wavelength end of the visible spectrum. This is precisely the opposite of what has been taught! This view assumes that at low light levels the long wavelengths of the visible spectrum predominate. Examples that corroborate this: to provide visualization at low light levels, i.e., under nighttime conditions, the military in “night vision” systems relies on sensing wavelengths in the near infrared region just beyond the red end of the visible spectrum. This is also the reason why we choose the color red for stoplights and for low light level illumination in aircraft cockpits. It is obvious that the optimum wavelength for low level vision, i.e., discerning at least the outline of the visual image at the lowest light level, is red.

Then, why does the sensation of color disappear under these conditions? It is not because of any lower sensitivity to light of cone receptors. Rather, color disappears because the intensity of light falling on either side of the fixed mid-band reference point at ~ 7-8 degrees of retinal angle falls below a level at which a color sensation-producing ratio can be determined by underlying neural circuitry. Moreover, this exactly corroborates the color vision theory of Edwin Land.

The historical misunderstanding about the supposed higher sensitivity to light of rod receptors is also now understandable. Taken singly, there is no physics based reason to believe that rods are more sensitive to light than cones. But, the preponderance of rods that comprise the periperal retina act in parallel to control dilation of the pupil of the eye at low light levels. Rods therefore do play a role in low light level detection..but only by virtue of their massive numbers! I have termed this complex of peripheral rods the “light meter” of the eye.

The assertion that rods are sensitive only to ‘black and white’ can also be understood. At low light levels when the rods have functioned to dilate the pupil the overall light intensity is not sufficient to activate the color signal on either side of the fixed mid-band point on the retinal surface. It is easy to see how these two separate effects have led to confusion about the properties of receptors.

The above assertions are corroborated very simply by the antenna/geometric model for retinal light interaction that I propose. In fact, I do not consider my thoughts an hypothesis at all but rather a rational explanation of data that has been accumulated in the vision science field for a hundred years!

GCH

A reprise of a Comment originally written in 2005. I think that this connection following from the geometrical aspect of my concept is interesting indeed. I have never been able to find Williams (see the link below).

“Edwin Land and Josef Albers both mused that the visual image in color was the “music of the eye” with the “score” (the image itself) being assembled from the “notes” (the individual colors). Auditory music has been described as “numbers coming (to the ear) in time”. Could it be that the color image represents analogous spatially distributed numbers? My representation of the retina defines a “spatial octave” (exactly eight rods fit around each cone) that very surprisingly, and never seemingly recognized, with the ratio of the size of cones to rods corresponding to the visual band (700-400 nanometers). Might there be some logic to the assembly of color wavelengths into a visual “musical score”? The twelve tertiary colors seem to correspond to the twelve musical tones as noted in an interesting paper by Williams (”A Look at the Musical and Color Scales”). Further, the harmony of the major CEG triad in music corresponds very closely to the scaled frequencies of the primary colors (RGB)”.

I have written elsewhere in this work about the role of the cholesterol molecule in the vision process. In summary, light interacts in the spaces between, and not within, retinal receptors. Energy from the interaction is transmitted orthogonal to the direction of incidence, i.e., in the plane of the pigment-containing thylakoid disks that are “coin stacked” within each receptor. The rhodopsin pigment molecules are contained within the bilipid membrane that forms the disks and are properly dichroically oriented to absorb energy from this direction.

Thus, light energy must be transmitted along (“in the plane of” or “through”) this membrane from the point of interaction on the receptor surface to the rhodopsin pigment molecules contained within the disks.

It is my contention that nature would have evolved a lossless mechanism for this energy transport. I believe that this has been accomplished in the form of the solitonic vibration. Solitons are a type of phononic (i.e., mechanical or “sound-like”) vibration that have the unique ability to transmit energy losslessly. An operative term here is coherent. A colleague of mine once used the analogy of wind blowing across a cornfield. Each cornstalk sways in the wind independently of the others with some “getting out of phase” the result being dissipation of the energy of the wind. This is somewhat the “general condition of things” and is the cause of red-shifting (i.e., energy loss) in biological light interaction. But, supposing that some sort of incompressible medium was placed between the individual stalks. The entire field would be constrained to move coherently and the energy loss from the random (some “out of phase”) swaying of individual stalks would be negated. This is the function of the cholesterol molecule contained within the bilipid membrane forming the thylakoid disk. The technical term is “intercalation”, i.e., each cholesterol molecule is of exactly the proper physical size to fit into the space between adjacent lipid molecules. Cholesterol-intercalated membrane allows lossless solitonic energy transport. This is the role of cholesterol.

I am always surprised with all of the attention given to the cholesterol molecule that this physics-based role seems never to be mentioned.

I have discussed elsewhere on this page the meaning of Hans Kuhn’s “photon funnel” experiment that supports the above assertion. Kuhn substituted the size-optimized octadecane molecule for cholesterol in artificial light absorbing (Langmuir Blodgett) layers and achieved what can only be explained by a lossless solitonic energy transport mechanism.

GCH

I am reading for perhaps the fifth time Arthur Koestler’s “Ghost in the Machine” (which I heartily recommend!). On page 78 Koestler, in a discussion of a hierarchy of physiological actions, reaches the topic of constancy – of size, shape and finally, color in the human vision process. This reminded me of how a logical explanation for the mechanism underlying the color constancy of vision is defined for the first time in this work. To wit:

The retinal surface contains a geometrically-defined area at 7-8 degrees that is spatially correlated with light refraction in the eye and located at the point where mid-band, i.e., 550 nm, wavelengths interact. Physically, this is the location where rod density is first sufficient to completely surround each cone. It is this spatial arrangement that geometrically defines mid-band. Light interaction at this location provides a wavelength-defining reference point from which all other wavelengths can be inferred/calculated to produce the color signal.

I would add that this geometrically-defined effect is in the nanometer (or, sub-optical wavelength) spatial domain. In fact, the entire hypothesis based on similarly dimensioned “optical wavelength antennas”. I will shortly write more about nanometer technology and its impact on the eye and the vision process. As anyone who reads the popular press knows this technology is under intense development, for example, in the field of semiconductor research. In this context one might even go back to 1993 and read “Optics of Nanostructures” in Physics Today (June 1993). With the development of “quantum dots and wires” one can see the connection with vision – retinal receptors are quantum wires! An example that I have cited – it has recently been found (references cited elsewhere in this work) that when light guides (read “retinal receptors”) are dimensioned in the sub-optical wavelength range light travels outside of the guide. All of the work that has been done modeling retinal receptors as traditional light guides must now be re-thought.

But…back to Koestler (p.78) on size constancy:

“The next stage in processing is very striking – once one starts thinking about it. If you hold the index finger of the right hand ten inches – the same finger of the left hand twenty inches, in front of your eyes, you see them as being of equal size, although the image on the retina of one is twice as large as the other.” (italics in the original)

K. obviously believes, and could not have believed otherwise, that the retina forms the image plane of the eye as depicted in those ubiquitous “inverted arrow” diagrams that populate vision texts…larger objects equal larger images on the retina.. But….on the Fourier plane retina an overall outline sketch of the perceived scene is detected on the all-cone fovea solely at the long wavelength limit of the visual band. Relative image size…? It would seem to me that image size is always the “proper size” for the image perceived .and any constancy is a mental construction and not related to the image formation process……”I expect all objects that I am in the habit of observing to be of a certain size no matter how they appear in my visual scene…and I will not take notice or be surprised”.

I will go on with this later but other things intrude…..

GCH

I had proposed in my original paper that the figures in the paper by Roorda / Williams (Nature, Vol.397, pp 520-522, 11 February 1999) portrayed regions somewhere beyond the one degree retinal angle claimed by the authors. This was based on the presence of regions of green and blue sensitivity (their Figure 3). The authors claimed that these were due to the presence of green and blue sensitive cone receptors and that the views represented the configuration of these different species of cones at one degree of retinal angle. .

I now believe that I misspoke and that the views did represent the distribution of color detection centers at this angle but that these are not due to the response of cones but rather seem consistent with my hypothesis. I also believe that the rather heroic imaging methodology used in these measurements probably portrays an accurate picture of the distribution of such centers and that it may be used to validate my model.

The authors state that their measurements were made at a retinal angle of one degree and that all of the color centers are cones and that therefore no rod receptors appear in the views. However, Wald in Figure 9 below taken from his paper (“Blue-Blindness in the Normal Fovea”, Jour. Opt. Soc. Am, Vol. 57, No.11, November 1967) recounting Osterberg’s data notes that at one degree the density of cones and rods is approximately equal at 40,000 per sq. mm. Now, I will grant that at this angle cone and rod receptor densities are falling and rising precipitously introducing the possibility of error in measurements made in this region. However, I believe a more logical explanation is that the measurements are accurate and are explained by my model.

At one degree of retinal angle, and as I have said previously, the smaller rod receptors are beginning to “intrude” in a statistical manner into the hexagonally ordered (and tight packed) array of larger cones (remember that although the densities of the two receptors are about equal the cones are almost twice as large as rods). Therefore, a statistical distribution of rod-cone appositions is observed (Osterberg) that I would claim form the green centers observed by R/W. As rod density rapidly increases a statistically smaller number of rod-rod appositions is present (again, see Osterberg’s figures) that I would claim correspond to the fewer blue sensitive centers in this region.

I have proposed that if R/W would extend their measurements to retinal angles beyond one degree they would observe an increasing number of green sensitive centers until at 7-8 degrees the field would be totally green, i.e., rod density is sufficient to completely surround each cone at this point presenting a field of green detection centers.

GCH