by Gerald Huth on February 3, 2011

The Nobel Prize in Physiology or Medicine 1967 was awarded jointly to Ragnar Granit, Haldan Keffer Hartline and George Wald “for their discoveries concerning the primary physiological and chemical visual processes in the eye”

Wald’s Nobel Lecture The molecular basis of visual excitation was presented on December 12, 1967. I particularly like the opening paragraph:

“I have often had cause to feel that my hands are cleverer than my head. That is a crude way of characterizing the dialectics of experimentation. When it is going well, it is like a quiet conversation with Nature. One asks a question and gets an answer; then one asks the next question, and gets the next answer. An experiment is a device to make Nature speak intelligibly. After that one has only to listen”.

Further in  the text Wald  describes the “distribution of color function over the normal human retina”. This description, specifically his Figure 15, is precisely consistent with my finding that  “nano-antenna” receptor appositional  sites  form the light interaction centers on the retina.

I have abstracted that figure with its accompanying legend from his lecture:

George Wald was  an  experimentalist

who objectively  reported  his findings even when (as I view it) they were at odds with the contemporary vision paradigm.  His data for this distribution of “color centers” is totally inconsistent with the thinking of the time  that  ”cone receptors detect color” and   rod receptors “possess greater sensitivity and a  black and white response”. This is a  mistaken belief (again, in my view)  that  persists even to this day and that has become dogma in the field of vision science.

NOTE: I must add a fundamental finding of this work that the sense of “color” is not detected at the receptor plane  and the term should not be used here. It was always a shortcut!  In place of the term “blue  sensitive cone” etc one should read “the rod-to-rod nano-antenna appositional sites that define the short wavelength limit of visual response”.

Wald first reports that the central all-cone foveal fixation area (i.e., to 1 degree of eccentricity) is “blue-blind”. He had  previously published this finding in a paper  “Blue-Blindness in the Normal Fovea”, JOSA, Vol. 57, No. 11, November 1967, to which  I have repeatedly made reference. This must mean that there are .no “blue sensitive” or “S” cones in the fovea – and the fovea contains >99% of all of the cone receptors. This has presented an historic dilemma for

which I can find no answer in the literature of vision. Wald’s finding seemingly has just been ignored preferring to envision a “retinal mosaic” as some sort of  biological  analogue of photographic film.

He  goes on to state that “from there to about 20-30 degrees from the fixation point is trichromatic”.

This is the exact retinal area that I have proposed is involved in  formation of the visual image. Trichromicity, however, is seen in  the nano-antenna order that is derived from the statistical distribution of  the two types of receptors. This order is comprised of  two regions whose lateral extensions correspond to the long and short wavelength limits of visual response separated by the geometrically-determined mid band reference point (the “Land point”). The subsequent  (in the bran?) sense of “color” is derived from a synthesis of  the light interaction from these two regions.

Regarding this mid band reference point, in the morphology of the retina there is obviously some tendency for  rods to associate with single cones  forming, at 7-8 degrees, a complete octagonal “eight rods around each cone” spatial order. It is this spatial order forming the 550 nm wavelength  that, in addition to explaining color vision,  is the basis for  the  heretofore unexplained color constancy of vision.

Wald goes on to state: “beyond this range, to perhaps 70-80 degrees out, the retina behaves as though red- or green- blind; and still further out as colorblind (monochromatic)”. This again is precisely as I have proposed – this region is populated entirely with rod receptors (albeit a very few widely distributed remaining cones). It is not at all involved in the image formation process but functions at the short wavelength end of the visual spectrum as a wide angle “light meter” controlling pupillary constriction and light entrance into the eye.





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