Dreams and Photoreceptors

I was awakened by a dream. Suddenly I realized it wasn’t a dream but I have wakened into a dream!

Dreams and Photoreceptors

I don’t know how exactly I have witnessed this dream by my own biological eyes. Just to mention human has an eye made of flesh and nerves connected to the brain, the neural network of nature, which has the capability of distinguishing image data. It works more or less similar to a manmade camera in many senses. Just my belief is human has made a prototype of natural eye using some metals, plastic and electricity. Though we can see images in a flat continuum [say its flat but it isn't at all flat;retina is spherical], I mean we use our eyes to understand images without pixels! Is that a miracle? How we can see things without any distortion or discontinuity even though eye is made of distinct cells that have sensitivity over light in discrete pattern?

Let’s simplify this question.

We can assume the retina, which is sole responsible to convert light signal through some sort of electro chemical reaction into ions that will enable to transport the light data to the brain along the wires of nerves. In this case retina is made of tiny special cells called rods and cones. Both cell types will convert light data into ions which carry signals along the neuron chains.

In this manner rod cells and cone cells will make the surface of retina as a continuum to catch the light image and proportionately transferring those quantum energies into energized electron radicals through the optical nerve. So we sense the imagery data.

My problem is, if these distinct cells or discrete cells arranged over an area must generate light signals individually and those must be acting as separate data loggers hence the image we should sense must be having dots of colors of image parts similar to a printed picture on a newspaper. Because individual light sensing cell produces its own signal and brain is suppose to capture the entire picture by assembling all together. But if this is the process, it is there a chance to reproduce the image as a combination of a data which was generated by individual cells. For example if we have rod and cone cells[these are actually not in the same proportion. Anyway!] in a matrix of 1000x1000 then the image must be having dots or signals of the same 1000x1000 matrix!

wow...this is so mysterious! Is that the Matrix movie all tells about this?

"No.. no... it isn’t, please don’t misinterpret. Matrix is a more general term. Not only the movie itself! ;)"

But in nature we can see objects without the dots of separation so called pixels in digital context.

How can this happen? Are the photo sensitive cells interpolating the missing data at their boundaries through an algorithm who acts in the brains visual area?

Or though we have this nature of discreteness in the seeing objects but we are unable to disintegrate the actual image?

Or are we really getting perception of totally delusional field of light integrated with a seamless color matrix?

My quest finally is whether we involved seeing aspects of retina while we are dreaming?

I was searching some fact sheets available in the web to investigate this phenomenon of the eyes, but I rarely found free content for these areas as shared research papers on the subject. But whatever my argument stands still for the clarity of the resolution of our own human eyes images which should be bound to the limit of the number of rod and cone cells.

If we carefully study the arrangement of the retina we can see these rod and cone cells are discretely organized on the sub surface covered with another membrane of transparent which covers and protect the retina from the internal fluid of the eye which makes the media for the light to travel through the lens to the retina wall.

Retina – A thin multi-layered sensory tissue that lines the back of the eye. The retina contains two types of photoreceptors called rods and cones. Visual information received by the photoreceptors is translated to neural signals by the nerves called ganglion cells. The rods are more abundant in the peripheral retina and work to detect light/dark changes as well as shape and movement. Cones detect color and distinguish fine detail which is why they are denser in the central retina, especially in the fovea.

So it is easy to understand the anatomy of the eye, which shows many details of the eye structure but I want to focus the subject into the retina. So shall I insert another link to pursue the retina in detail?

The human retina contains approximately 120 million rod and 1 million cone photoreceptors. The figure below illustrates that the distribution of photoreceptors across the retina is not uniform. Cone density is highest at the fovea, where recent estimates place it considerably higher than the figure above suggests -- approximately 300,000/mm2; rod density is highest at about �18 degrees eccentricity. Rods are actually absent in fovea (which is why dim stimuli, such as stars, cannot be seen when gazed at directly, but become visible when images slightly eccentrically -- to the side -- where rods are plentiful). Primates and birds have true foveas (some birds, notably hawks and eagles, actually possess two foveas per retina!); other species such as squirrels, cats, dogs, deer, etc., have a less dramatic regional specialization, and possess what is called an area centralize or a visual streak.

What we can say finally? The human eye is the most High Definition screen for mankind rather to the manmade LCD or LEDs upto now. Isn’t it?

But my quest remains. What about dreams? Are they High Defined or not?

1 Response to "Dreams and Photoreceptors"

Dinithi Pavithra said...

... excellent article .. keep it up!! :D

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