I first comment on the problem of perception of 3D world "out there" constructed with 2D retinal information. All the processes that convert that information in to a highly compressed (nearly by a factor of 100) data stream in the optic nerve are well understood. The most of the information via the LGN comes to the cortical called V1. That which goes elsewhere permits what is known as Blind sight (but I will not speak much of it as it mainly gives minor assistance to vision, with little of no perception - Monkeys with V1 removed, can still pick up a nut from the floor, without groping for it. A larger fraction of their retinal data than in humans goes directly to the superior colliculus that does this. In non-humans that area of the brain is usually called the Tectum.) Many who concern them selves with visual processing gloss over the first problem in V1. Namely how does the continuous 2D field of neural excitation get parsed into discrete objects. My suggestion for how is discussed in detail in the Ref. 1 of the link below - a paper I published back in 1994. I was studding what is known about how nerves of the brain interact. Here is a discussion of that: http://toritris.weebly.com/visual-system-3-v1---line-detectors.html Hubel & Weisel got the noble prize for the discovery of "line detectors" in V1, which BTW they are not but all call these orientation sensitive cell "line detectors." Those cells are more complex than H&W realized. The stimulus that H&W presented to the money with indwelling micro-electrodes in V1 was field of uniformly spaced parallel black on white lines on screen they could rotate. (So no need to control where the money was looking). If you do a 2D spatial Fourier (Gabor function more correctly) on that grid pattern stimulus, Yes it has strongly spiked orientation, but also a strongly spiked spatial frequency. Their cells are, I am nearly sure are detecting both. I.e. those H&W cells are actually doing a transform of the visual field to "Fourier like" space. See figures A, B, C &D here: http://mri-q.com/uploads/3/2/7/4/3274160/fourier_transform_and_ph_enc.pdf The last, D, is a well known photo of president Lincoln in both normal form and in the Fourier transform - both contain exactly the same information; however, the FT version does not change if the original image from the real world is shifted a foot left or even if made half as large (but the scale of the FT does change in this second case,) BUT NOT THE RELATIVE WEIGHT of the components. - That makes identification of object in FT space independent of factors, like location, that don't change what the object is. Why I believe, and experiments suggest, the brain operates on the FT version of the field of view at later stages, say in the temporal lobes where object identification is done. But still they need first to be parsed into object from the continuous field of neural stimulation in V1. In my next post is how, I believe that is done (compressed version of first part of Ref 1 of link below). here is more related to ALL perception I hope reader will find interesting: http://www.sciforums.com/showpost.php?p=905778&postcount=66 there I explain and justify my RTS view of perception with focus on showing genuine free will is not necessarily inconsistent with the natural laws that control the firing of every nerve in your body. Then see: http://www.sciforums.com/threads/wh...e-will-an-illusion.104623/page-5#post-2644660 and posts 84,86 & 94 where I clarify my POV more. Next post here will return to the more narrow question as to how do neurons parse continuous field of stimulation in V1 into separate "objects" for later brain stages to identify.