28 April 2017

VISUAL DYNAMICS II: THE ANATOMY OF VISION


Before we make any major advances into detailing how the eyes perform their function in-depth, that it to say the transformations taking place within the structure, it is going to be necessary to acquaint ourselves with its organic form in the outer.


This will not be an extended investigation into the structural properties of the eye as it is only necessary to harness the essential features of the instruments we are dealing with.  This outline will clarify the most significant properties of the external features to avoid getting lost in meandering analysis and pointless detail.  However, let it be stated that the levels of structural complexity within these organs is so great, and the symphony of actions taking place within them so subtly harmonious, that it would take several exhaustive volumes worth of material simply to relate the entire known dynamic in any real measure of detail.  For our edification as Artists, it is unnecessary to comprehend the entire structural properties of the eyes, only in relation to how they perform as sense organs appropriate to the experience of our work, so we will isolate the most relevant material and cut away the chaff where we can.

Let us make another thing clear before we begin.  This material is our entry point into the subject of sight, not the destination.  And as Artists, we should understand at least some of the important organic functionalities of our most essential instruments before we attempt to make any profound statements about the Art subject that mediates our sense of the world.

For we cannot say anything significant about Art until we understand the organism that creates Art.

When most of us look in the mirror and notice our eyes, we are really noticing five main criterion: 

the PUPIL, 
the IRIS, 
the LIMBUS,
the SCLERA,

It may not be immediately perceived, but there is also a transparent film residing on the surface of the eye called the CORNEA.  These are the subjects that make up the major external properties of the eye on the borderlands of visionary technology.



So let us examine each of these structures in sequence and contextualise their position starting with the Cornea.  In order to perform their function, the eyes obviously need to be exposed to the environment they will interface with.  Like fishermen on the sea, they require an interface with the very element that they will be dependent on for harvesting of their bounty.  That element namely being, light. 

Light is the primary that informs the language of sight.  It is the base material for all subsequent styles of conversion into the visual language.  And the first point of contact on the eyes that this precious material comes into contact with is the Cornea.  The Cornea is a manipulator of the light signal, serving to focus the light that reaches the eyes by bending and refracting the light onto the lens of the eye.  The lens transmits that refracted light within the structure eye for further processing.  Despite it's transparent and seemingly insubstantial appearance, the Cornea counts for approximately two-thirds of the eyes' optical power, that is to say, the organs agency to manipulate incoming signals not the degree of energy or power within the total structure of the eye itself.  It also serves to protect the organ from unwanted foreign bodies such as dust, liquids and bacteria from the external environment.  Damage to the Cornea can result in a corruption of the incoming light signal, with vision appearing too distorted or too blinding.  


So how does the light pass through the membrane of the Cornea, onto the lens and then into the very structure of the eyes for further processing?  As we discovered, incoming light is refracted by the Cornea and passed on to the Lens.  The opening through which this light is allowed access is via the Pupil which is noticed by the circular black space in the very centre of the eye.  It is literally a void in the centre of the eye.  This opening has the ability to expand and contract as a way of reacting to incoming light signals, typically a greater light source dilates (contracts) the Pupil whereas a weaker light source makes the opening expand to allow for more potential light to be processed as a compensation for the loss in signal.  The mechanism by which the Pupil is allowed to expand or contract is controlled by small muscles in proximity to the Pupil, in the region of coloured tissue named the Iris.  Eye colour is determined by a special pigment cell called Melanin.  These cells can be found in most optic organisms and are also the same cell pigments that determine skin colour.  The less melanin content in the iris structure will mean a fairer colour, the more melanin content means a darker colour.  A deficiency in these cells contributes to the condition known as albinism.

As we approach the outer periphery of the Iris the colour deepens into a dark band around the circumference.  This is the regional border between the external Cornea and the large white regions known as the Sclera.  The border is populated by mysterious structures known as the Palisades of Vogt, claimed so because their exact function is still unknown to science, although some speculate that they may play a role in the ageing and maintenance of the cornea. 'Vogt' is a Germanic term referencing a lord of guardian over a particular territory.  Another interesting mention about the palisades is that their arrangement appears unique to every given individual, making them compatible to fingerprints.  It is worth mentioning these unusual regions if only to indicate that the full dynamics of the visual organs is not yet comprehended much like many other mysteries of organics.  Even with such sophisticated optical technology the body still invites inquiry.

Finally, we break out into the outer regions.  The Sclera covers the largest visible area of the eyes and is indicated by its opaque white surface.  The Sclera is given its white colour via the sclera proper, a thick white tissue coated with a membrane of mucus that lubricates the eye part.  However, there is more interesting functionality regarding this zone of the eye than mere hygiene.

In humans, this region is always white however in other mammals the tone of the coloured Iris compares to the region of the Sclera giving the appearance of a large field of colour with no whites. 

It has been speculated that the prominent whites of human eyes compared to other animals, may have evolved due to the way that human creatures use their eyes as an instrument of social communication (I shall speak to this in greater detail later).  Eye contact in primate groups is used as a means of intimidation and the creation of a social hierarchy.  Research with humans and their domestic dogs have indicated that these animals may also be able to respond to socialised visual communication although at a much lower dynamic range than humans.  So, despite these specific regions of the eyes possessing inherent properties responsible for tasks ranging from hygiene to light displacement, the ingenuity of the human creature has responded to the visual contrast between the eye regions and adapted this into a means of social manipulation.  This is visual dynamics: the unique consequences of vision expanded into wider potential via evolutionary creativity.

The significance of an elementary understanding of the physical properties of the eyes are not to be understated.  There is much more to be said about vision outside the domain of biology and despite the general fashion for reductionism in our age we cannot glean a comprehensive understanding of the true dynamics of a complex system by merely reducing its properties down into base matter and declaring that density our enlightenment.  By the same token, if we do not acquaint ourselves with the essential properties of a system, then all continual statements might be marked upon unsupported foundations. To glean a mature and truly rational response from a multifarious subject such as sight, it demands a multi-disciplinary manner of investigation.  As I stated in the introduction to this series, this multifarious approach to research will characterise our meditation on the expanded nature of vision and creative studies.

In the next feature, I will briefly speak to the relationship between light and the organism, before we travel beyond the surface of the eyes into the inner chamber, where light becomes a language in a symphony of metamorphosis.

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