2 May 2017

VISUAL DYNAMICS IV: THE ORGANIC SYMPHONY OF SIGHT


So far, we have delineated the outer regions of the visual instruments.  Now we are finally ready to travel within the inner structure of the eyes and seek clarity surrounding the manner that the incoming light signal is captured, processed and harmoniously translated into a symphonic rendering of sight.


THE INNER EYE

It is a common misunderstanding that 'seeing' is done with the eyes.  On first appraisal, it is easy to understand why considering that vision is obliterated when they are enveloped and that damage to the eyes is common, resulting in blindness or various other forms of visual impairment.  In reality, this impairment is due to the fact that the preliminary organs responsible for harvesting the light signal have been corrupted whilst the secondary organ responsible for actually translating that signal into a visual rendering remains intact.

The eyes are largely responsible for light harvesting and pre-processing of the light signal and they operate on the borderlands of the bodies' domain, interfacing with the external fields for the seizure of light that compliments the subsequent post-rendering processes within the deep brain.



We already understand that the incoming light is making contact with subjects in the environment, partially absorbing and refracting off those subjects that eventually come into contact with the visual organs themselves.  The first point of contact occurs at the region of the cornea, the translucent membrane that envelops the outer eye.  The cornea serves the unique purpose of further refracting the light towards the part of the eyes known as the lens.  The lens serves to continually focus this refracted light signal into the inner chamber for processing.  Like the pupil, the lens has the ability to alter its shape which consequentially influences how the light signal is focused.  When we want to hone in on fine details the lens contracts, thereby manipulating the light signal at higher intensities.  When we want to observe objects from a distance the lens muscles relax, thereby broadening the signal range.

We also know that the passage through which the incoming light is travelling can also be controlled.  The sensitive muscles that surround the pupil have the ability to contract or expand which controls the amount of light that enters the inner chamber.  This a reflexive response to the environmental conditions: darker conditions will cause the pupil to expand thereby allowing more light in to compensate for the lack of signal, with pupil contraction occurring in light abundant conditions so as not to overwhelm the optics with more information than it can process.  This is what happens when we are 'blinded' by too much direct sunlight, as the range of light signal becomes too much for the brain to process, but also, our reaction to wince and retract from the sunlight is an automatic reflex to protect the inner structure of the eyes from ultraviolet radiation.

So, already we can tell that there is quite a complicated degree of refinement even before the light has been passed into the inner chamber of the eyes for further pre-processing.  The light modulating filters in the cornea, pupil and lens are conditioning the signal in preparation for its contact with a highly significant arrangement of the internal structure of the eyes known as the Retina.


ELECTRIC LIGHTS

The retina is comprised of several features within its design which aim to convert light into a bio-electric signal that the brain, in its mastery, will translate into a rendering of the visual world.  The retinal formation occurs early when we were still in our embryonic state and its development alongside the early stages of brain formation include it as part of our central nervous system (CNS).  We will not pursue a thorough explanation of all the retinal parts here, only to focus on the essential components of its design that are informing the roles of light conversion.

The retina is comprised of an intricate layer of modules called photoreceptors; these are split into two distinct categories that process the light called rods and cones.  These rods and cones are responsible for the conversion of light into bio-electrical information that then travels beyond them and into the deep brain for post-processing into a visual image.  The retinal space is covered by approximately 7 million cones and over 100 million rods to supply this task.  These modules are also specialised to stimulate in response to specific conditions that compliment the incoming light signal.  For example, rods activate during periods of dim light and are useful in facilitating a monochromatic visual response.  Cones, on the other hand, activate prominently during environments where there is a healthy abundance of the light signal and aid in the perception of colour ranges.

Both of these receptor types contain synaptic outgrowths that react to the pre-processed light signal entering into the eye structure and correspondingly, convert that into a bio-electric response.  Rod and cone interpretations can be combined into new information complexities before they are passed on to the optic pathways that will relay their messages to the deep brain.  The information highway that relays that signal onto the brain is called the Optic Nerve.



The optic nerve is a connection between the visual organs and the specialised portions of the brain responsible for visual translation.  It is the connection that relays this converted signal, now converted into bio-electrical information, on towards the specific areas of the brain for the final translation into a complex visionary impression.  The optic nerve has networks that both run both directly and intersect over into the adjacent hemispheric points of connection in the brain (as seen above).

So, now we have followed the light path making contact with the outer reaches of the eyes, being contorted by various filtering regions before being passed directly into the inner reaches of the organ itself, where this luminous element is dissected and converted into a bio-electric signal.  This converted signal embodies the new information that will compliment the great rendering of our visionary experience.  Despite the complex architecture of the light harvesting organs, they are simply not capable of discriminating between the necessary details within the electrical signal that transfigure that code into a detailed and interpretable impression of the visual world.

The first arrangements in our symphony are complete.  However, for the complete dynamics of the organic composition to reveal its full potential, we will have to account for the final, and most significant stages of this dynamic process.  A process that occurs within the regions of some of the deepest and oldest parts of the brain.


THE VISUAL CORTEX

The optic nerve has sent the filtered bio-electrical signal from the optics and is relaying it to the region of the brain responsible for the post-processing and distribution of the signal.  This region is called the Cerebral Cortex.  The cerebral cortex informs a huge part of our daily function such as language, verbal memory and sensory interpretation.  A portion of its mass is also what facilitates the experience of seeing.

The optic nerve is connected to a specific region of the cerebral cortex called the primary visual cortex or V1.  Due to this direct interconnection between the optic nerve and V1, it was previously assumed that this region, and only this region, was responsible for the processing of the visual signal.  Now we understand that whilst V1 is primarily involved in the immediate acquisition and distribution of the signal, it is also passed on to other regions around its proximity that specialise in various methods of discrimination and visual processing.  We could say that one sees with the V1 cortex and then understands 'what has been seen with the various specialised regions that collate the bio-electrical message into a harmonious symphony of visual experience.  The various regions are specialised in their sensitivities to various aspects of visual acuity and can cross-reference information with each other provided enough inter-connectivity is present between them.

The bio-electrical signal is discriminated in V1 in two different ways.  For simplicities sake, we will call them a 'where' and a 'what' stream.  The 'where' stream is concerned with spatial recognition in the environment and excels in coding locations of subjects, whereas the 'what' stream is concerned with object recognition and highlighting detailed specifics of a subject.  The regions of V1 and V2 on its periphery, are responsible for the distribution of the respective signals into the adjacent areas where it can receive their more specialised attention.



The area of V3 is where dynamic shapes and boundary definitions are translated, a key requirement in the creative construction of visual images.  The specialised cells that do the organising are called Orientation Sensitive Cells (OSC's).  There are certain types of these cells that are biased towards particular currencies of orientation: one type might stimulate to horizontal definitions, others to sharp bends, etc.

The intricacies of the area V4 is still a subject of discussion.  It's cells do seem to stimulate concerning variations of colour whilst not being wholly responsible for colour representation across the cortex.  Individuals who's V4 zone has been damaged often report a world tainted by "dirty" shades of grey.  Still, more of the exact properties regarding the processes and responsibilities of V4 has yet to be comprehended.

Movement is translated by the visual cortex's V5 region.  These cells are excited by irregular and expressive movements and are indifferent to colour due to the poverty of connections with V4.  The dynamic effects of fire have proven to be especially stimulating to these cell receptors, with its alternating slides between smooth waves and sharp flourishes of movement.  This would also suggest the hypnotic effect that fire has over the human temperament: we are effectively doping ourselves with cortex electricity as it reacts to the undulating patterns in our visual field.

Now we can accommodate a basic impression of the processes at work when we are contemplating a visual subject.  As visual artists, the element that we are primarily creating with and depend on to appreciate those creations is reconstituted light.  This reconstituted signal is then being fed through various specialisations of our organics and in their synthesis, yielding a sophisticated impression of the visual world.


THE ORGANIC SYMPHONY 

It is most appropriate to adress this process as a 'Symphony.' When we isolate and discriminate between the various parts of an orchestra we can see that each is comprised of a specific function and unique identity that works alone, and also in tandem with other instruments to inform the greater dynamic composition of the signals that we interpret as music.  It is the sophisticated interaction of these specialised parts that produces not a wall of cacophony, but an organised and harmonious translation of sounds into a sensory work of art.  We can transfer the blueprint of this analogy over to our appreciation of the visual systems in the human body, isolating and discriminating between the various specialised instruments of the visual body, each responsible for their unique role in an ever-greater transformation of what initially began as electromagnetic radiation from a star and now, weaves harmoniously together within the great translator of experience in the visual cortex as a dynamic sensory rendering of the forms of phenomenal life.

I will reiterate what I stated in my first entry on visual dynamics: that in order to become more conscientious and effective as artists, we have to initiate ourselves within a fundamental understanding of what informs our craft beginning with a preliminary education in the properties of our own organism.  For in its magnificence, our body is continually creating so that we might create.
The unique consequence of our evolved responses to life has united to perform this symphonic rendering of Transcendent Nature.

Nature has become sentient in us and we are the eyes with the corresponding intelligence and creative dexterity to reflect upon its own creation.  The deep dynamics of these organic systems in the brain have still not been satisfactorily fleshed out by modern science, nor I might add, successfully translated into a satisfactory system of comprehension by living psychology.  The brain is still a great, wild frontier for the sciences.  During our lifetime, there will certainly remain many fields of activity that remain elusive and mysterious, and no matter how much the rationalist academics might protest, as our comprehension of the organic systems accumulates so will our received perception over what may, or may not, be interpreted as 'reasonable.'

We have at least secured a material initiation to our process of uncovering the visual systems that inform the human experience of life.  Yet, our journey has just only found its feet.  Now we will begin a familiarisation with new styles of information that will further expand and contextualise our understanding of the visual states into a holistic appreciation of visual dynamics.

For now, we can at least say that we have satisfied the organic elements of our composition.  There may yet come a day when more is revealed concerning the deep complexities of the human nervous system and the bodies' ability to generate the audio-visual signals that compliment the visual world.  For now, we can only go on what we have, and what we have is provocative enough, even as an open book.

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