REPLY TO A COMMENT

by Gerald Huth on February 25, 2011

I have received a very thoughtful comment regarding my work. I will reply point by point interspersing my thoughts with the text. This may finally get to the fundamental difference between this interpretation that is based on modern physics and the traditional biological view of the retina (I am convinced, however, that my attempt to break through what I term years of misunderstanding will continue to fall on deaf ears!).

For the record, light photons do not “rain down” on retinal receptors interacting with pigment molecules in some statistical “photon catch” scenario !  Rather, this biological structure evolved to detect the wave nature of light interacting directionally with “nano-antenna”  spaces formed by the appositions between individual receptors. Furthermore, this interaction occurs in heretofore unconsidered dimensions of space and time that are now at the forefront of our measurement capability (femtosecond spectroscopy, for example).  A new understanding of the vision process follows from this realization.

But to the reader…please realize that what I am about is physics – the pure physics, describing in modern nanotechnology terms, light interaction with the outer segment of retinal receptors and ultimately demonstrating  where this leads in understanding the vision process. These physics describe an interaction in space and time that is entirely new to vision science in the sub-micron spatial domain and on a time scale that is at the limit of our ability to measure experimentally – femtoseconds.  This generally describes the regime of quantum physics. (Although not associated with vision, I note even today a report of a finding of  “quantum antenna” structures ‘Quantum antennas’ enable exchange of quantum information between two memory cells. There is much teaching in this report.)

So very much of the vision process is explained by this realization. Further, this is not a new “theory” but exactly explains and is derived from fundamental experimental measurements that have been made in the science of vision that date back to the initial determination of the trichromicity of the process and Osterberg’s 1935 accepted measurements of retinal topology.. The concept of light wave-interactive “nano-antennas” makes clear for the first time that determination of the sensation of “color” does not reside directly in the process of retinal light interaction. This assumption has been a “shortcut” that has taken our thought process far astray. Edwin Land’s seminal work on the perception of color is finally explained together with such historically unexplained phenomenon as the color constancy of vision  and finally, a quantitative understanding of the eye’s ability to discern the interaction of  single quanta (photons).

I have been told on occasion that “if I only had studied biology…I would understand the situation etc.” (this point will become evident in the text that I will critique below). It seems clear that in these later years vision science has become the province of biologists, geneticists, etc, with precious little physics input. Indeed, I suppose there seemed very little that physics could add if the reaction time of the eye was accepted in the biophysical sense as functioning in the millisecond time domain.

In this regard, I find interestingly that the most cogent contemporary vision results are in the engineering discipline of computer vision (I have noted for, example, work in this field on a spiral algorithm for forming the visual image that is in concert with this work).

But (finally) to the Comment (original in italics with my response in capital letters):

“Blue” cones do exist. We know this. We have isolated them. We have tested their responsiveness in the retina in vitro and in vivo. We know they are different from “Red” and “Green” cones. We know their connections to ganglion cells and from there on in the LGN and visual cortex. They do exist.”

THE ENTITIES THAT I WOULD PROPOSE YOU HAVE ISOLATED SHOULD PROPERLY BE TERMED “BLUE SENSITIVE LIGHT INTERACTION SITES. IN THIS WORK  THESE SITES ARE SHOWN TO CORRESPOND TO THE HISTORIC AND ACCEPTED MEASUREMENTS OF THE DENSITY AND DISTRIBUTION OF BLUE SENSITIVE CONES THAT YOU REFER TO.  THESE SITES ARE NANO-ANTENNAS FORMED BY THE STATISTICALLY  DISTRIBUTED, AND RARE NEAR THE FOVEAL EDGE,  ROD-ROD APPOSITIONS. I HAVE CRITIQUED IN-EXETENSIO THE IN-VITRO MEASUREMENTS THAT I BELIEVE YOU MUST REFER TO – AND FOUND THEM VERY WANTING – INTERROGATING A SINGLE RECEPTOR LENGTHWISE ETC WITH ALL OF THE ATTENDENT QUESTIONS. THE IN-VIVO MEASUREMENTS MIGHT REFER TO THE WORK OF ROORDA ET AL AND, AS I HAVE EXPRESSED, THESE MEASUREMENTS AGREE AS TO POSITION AND DENSITY EXACTLY WITH THE NANO-ANTENNA FINDING – NO ORDERED “MOSAIC”.

I BELIEVE THAT THE IDEA THAT SUCH CONES EXIST DERIVES FROM AN ATTEMPT TO SEE AN ORDERED “TRICHROMATIC MOSAIC” THAT WOULD BE THE ANALOGUE OF PHOTOGRAPHIC FILM WITH THIS THINKING  CONTINUING EVEN TODAY. THE REAL ORDER IS THE FINDING IN THIS WORK OF A TRICHROMATIC, NARROW WAVELENGTH-RESPONSIVE ORDER THAT DERIVES UNIQUELY FROM THE EVOLVED STATISTICAL MIX OF TWO SIZES OF RETINAL RECEPTORS .

“The conformation of cones in the retina is basically random”

I REALLY DO NOT UNDERSTAND SUCH A STATEMENT.   MEASUREMENTS OF THE TOPOLOGY OF THE RETINA CONSISTENTLY SHOW THAT THE ALL-CONE FOVEA IS COMPOSED OF HEXAGONALLY CLOSE PACKED CONES AND THAT THE POINT AT 7-8 DEGREES – THE “YELLOW SPOT” –SURPRISINGLY EXHIBITS COMPLETELY ORDERED OCTAGONAL PACKING.

“Only in the fovea midget cones are virtually the only population, and with increasing eccentrities  (sic) they become sparser. It is true that midget cones in the fovea are arranged hexagonally, and rods in greater eccentricities octagonally – it is the most efficient way to pack things together.”

THIS SEEMS TO AGREE WITH MY ABOVE STATEMENT BUT, WHAT ARE “MIDGET CONES”?  I REALIZE THAT THERE IS SOME DIFFERENCE ACROSS THE RETINA IN THE SIZE OF CONES BUT I WOULD PROPOSE THAT THE GENERALITY THAT TWO (MAJOR) SIZES OF RECEPTORS – CONES AND RODS – DESCRIBES  RETINAL TOPOLOGY.

“But this doesn’t mean much other than that cones are quite sparse outside the fovea – their arrangement is random and it’s not true that there is one cone in the centre of an octagonal arrangement of rods.”

PLEASE REFER TO PLATE 6 FROM PIRENNE’S “VISION AND THE EYE” WHERE THE  COMPLETE OCTAGONAL MOTIF IS DIAGRAMMED. THIS IS DATA THAT WAS OBTAINED SOME SEVENTY YEARS AGO !.

“Remember, the retina is a biological apparatus – it is not precisely arranged and cannot be so”

THIS IS THE CRUCIAL POINT OF THIS WORK AND I WANT TO EXPRESS IT AS CLEARLY AS I CAN. THE NANO- (“NEAR FIELD” OF OPTICAL WAVELENGTH) SPATIAL DOMAIN IN WHICH NANO-ANTENNAS FUNCTIONS ONLY IN THE LIVING STATE OF THIS BIOLOGICAL MATERIAL. IT’S  SPATIAL ORDER IS EXQUISITELY EXACT. ELECTRON MICROGAPHIC VIEWS OF BIOLOGICAL MATERIALS REPRESENT THE DISTORTED STATE OF DEAD TISSUE AND HAS HISTORICALLY OBSCURED THE PRESENCE OF THIS NANO-ANTENNA MECHANISM.

“It is not the distribution of cones and rods that mediates vision at the retinal level, rather the underlying connections between horizontal and amacrine cells and other cones and bipolars, that determine how things are put together”.

THIS GETS NTO THE UNDERLYING SLOWER BIOPHYSICAL  (OR CHEMICAL) SIGNAL PROCESSES THAT I DO NOT DISPUTE. THE NANO-ANTENNA LIGHT INTERACTION SITES CERTAINLY CONNECT WITH THESE UNDERLYING BIOPHYSICAL LOGIC FUNCTIONS.

“Rods play no role in colour vision”

CONE-ROD NANO-ANTENNA APPOSITIONS AT 7-8 DEGREES OF RETINAL ECCENTRICITY FORM THE GEOMETRICALLY DETERMINED MID-BAND WAVELENGTH NECESSARY AS EDWIN LAND FOUND UNDERLYING THE SENSATION OF COLOR. THIS SEEMS TO PARROT THE ERRONEOUS THOUGHT THAT “RODS DETECT“BLACK AND WHITE” – SEE MY LAST COMMENT ON SCOTOPIC AND PHOTOPIC VISION .

“They saturate at very low light levels. They DO still signal at higher light levels – but that’s why cones are so much less sensitive.”

IT IS THE LARGE TOTAL AREA OF ROD-CONTAINING RETINA THAT HAS LED TO THE HISTORICAL MISINTERPRETATION THAT RODS ARE MORE SENSITIVE TO LOW LIGHT LEVELS.

“For a cone to signal light, the signal needs to be about 12 times more than that a rod can possibly signal. Otherwise there’d be too much noise.”

AS EXPLAINED IN THIS WORK, “NOISE” – AND I PRESUME THE WRITER MEANS ELECTRICAL NOISE – IS TIME SENSITIVE – IF SUCH NOISE CORRESPONDS TO RANDOM ELECTRONS, THE SHORTER THE “TIME WINDOW” THE LESS NOISE. AS LONG AS ONE CONSIDERS THAT THE VISON PROCESS OPERATES IN THE SLOW MILLISECOND TME DOMAIN ONE WILL THINK THIS WAY. NOISE IS ELIMINATED IN THE ULTRA-SHORT FEMTOSECOND TIME DOMAIN AND THIS EXPLAINS AS I HAVE NOTED THE ABILITY OF THE EYE TO “NOISELESSLY”  – IN CONCERT WITH A SIMPLE POISSON CALCULATION – DETECT SINGLE QUANTA…PLEASE!

“It is not taught that rods are “light or dark” detectors. Far from it. We know that rods’ primary role is vision in very low light levels – night vision basically”

AS I NOTE ABOVE

“There are people who are born without cones – they only see black and white (well actually a bit more green),

AS THEY SHOULD – THEY HAVE NO ADMIXTURE OFTWO SIZES OF RECEPTORS TO FORM THE GEOMETRIC NANO-ANTENNA BASIS FOR LAND’S COLOR PERCEPTION.

“and they need to wear special sunglasses because otherwise in photopic conditions they wouldn’t see anything. “Light or dark” detection is mediated by a separate system”

AGAIN, SEE MY LAST COMMENT ON PHOTOPIC AND SCOTOPIC VISION.

“Every cone synapses on two separate populations of bipolar cell – an “OFF” population which expresses ionotropic glutamate receptors, thus depolarizing the cell when the cone releases glutamate, which happens in the dark – remember cones hyperpolarize to light. This population signals a reduction in light levels compared to background. The “ON” population carries glutamate GPCRs (mGluR6), which initiate a cascade in response to glutamate which hyperpolarizes the cell – meaning that in the absence of glutamate and thus presence of light, they fire.”

MORE BIOPHYSICS THAT I ACCEPT – BUT NOT RELEVANT HERE.

“Anyway, point is: I think your idea that the distribution of cones and the physical properties of light and the retina can underlie certain things in vision has merit and should be explored further. But please, do not dismiss what we know about the biology of the retina. I think that if you better examined our current knowledge of the retina, you would be able to more precisely modulate your theory.”

WELL….?

Respectfully submitted,

GCH

Revised 2.26.11

Ojai, CA/USA

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