- Introduction
- Recap
- Objects
- Object relations in woodcuts
- Object relations in LWS-N
- Additional
- Conclusions
- References
This post builds on reference 1, something of a new departure for LWS-N (introduced getting on for two years ago at reference 9), to describe anew how LWS-N builds objects from a sheet of neurons, for projection into consciousness.
The search key ‘srd’ has now been upgraded to ‘sre’ in honour of this new departure.
Recap
To recap on what was intended as a suggestive story at reference 1, we have our 4 square centimetres of unit square, populated by a two dimensional array of one million neurons, more or less arranged in 1,000 rows and 1,000 columns. While our more usual assumption has been that LWS-N is 5 square centimetres in area, containing 100 million neurons, more or less uniformly distributed over that area. No split into a left hand part and a right hand part, in the way of most brain structures. No maculae or foveae after the way of retinas – at least not yet. On the other hand, we might well allow eye movement within a frame of consciousness, to keep the frame strong and up to date. Eye movement which does itself not make it to consciousness.
Figure 1 |
Figure 2 |
Figure 3 |
Figure 4 |
Figure 5 |
The span of a region will be connected although it may contain holes. It will be very roughly convex, that is to say, holes apart, it will contain its interior.
Spans of distinct regions may intersect, may overlap. Indeed, the span of one region may be inside the span of another.
The present post tries to carry the story of reference 1 into the expression of visual objects from the outside world, objects with edges, shape, textures, position relative to the subject and position relative to other objects. More or less the layer objects about which we have posted before.
Some of this is described by the soft-box model above. In which:
- Active neuron is distinguished from neuron, with one of the former belonging to exactly one region
- We allow parts to contain more than one region, thus allowing colour and texture to vary within a part. Not further discussed in what follows
- Frame is added left to remind us that what you get here is very transitory, unlikely to be lasting more than a second or so
- We assign neurons to positions on our unit square, despite neurons being far from point objects, as already noted above
- We have omitted spans, which need their own model.
Objects
An object is a subset of the set of neurons in our unit square, all firing at the same frequency, which is maximal in the sense that there are no neurons just outside the object which have that same primary frequency. Two different objects can have the same primary frequency but there has to be a reasonable air gap (as it were) between them.
We do not require an object to have exclusive rights over a patch of our unit square, with some overlap being shown in the figure above.
But we do require an object to have a reasonably simple boundary with the rest of the world, the black line in the figure below, to be made up of a small number of straight lines and smooth curves. As the boundary gets more complex, the object is more likely to be lost in the background, not experienced as an object at all. This lack of experience corresponding to a lack of a coherent travelling wave of activation both spanning that object and distinguishing it from its background.
Figure 6 |
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Figure 9 |
Figure 10 |
Figure 11 |
Figure 12 |
With the issue here being that the brain might work all this out, but how does it express the answer in LWS-N? Can it do so within the confines of one topically organised layer, or does it need another layer to carry some supplementary information. Issues which we have been turning over for at least a couple of years. For which see, for example, reference 2.
A simple answer might involve forcing exclusivity, for each object and each part to have exclusive occupancy of its bit of two dimensional space. But such a simple answer allows neither for our knowing more about the objects than can be seen from a single point of view nor for objects and parts being transparent – and while ancient man might not have had glass, he did have water.
Object relations in woodcuts
Figure 13 |
- Looking at the real thing, where we started
- Looking at the real thing, through a window, reduced and framed by that window
- Looking at a colour photograph of the real thing hung on the wall
- Looking at a black and white photograph hung on the wall
- Looking at a full colour painting hung of the wall
- Looking at a black and white woodcut hung in the wall
- Looking at a reproduction of such a woodcut, what we have here
Roughly in descending order of proximity to the original, whatever that might mean. And the thought is, that the woodcut, with its very limited range of expression, is perhaps closest to, or at least comparable to what LWS-N has to do when turning the firing of a small sheet of neurons into the subjective experience of the scene.
So we turn now to object relations on a woodcut, with one such being reproduced by telephone above – not bad full screen on this laptop, not good inserted in a Word document – reproduction which does include image processing artefacts, for example in left hand end walls and in the sky – but which still serves the present purpose. With the immediate interest being the tricks and techniques the woodcutter uses to generate a sense of the real, using what might be thought to be a medium – a flat block of wood – which was not terribly promising. The idea of a woodcut being to cut lines and areas out of the wood, leaving what is left to print black – which means that the simplest motif is a white line on a black background – as in Figure 16 below.
The way that the brain delivers all this to LWS-N is a quite different matter to which we will return in due course. The present thought being that in doing this, the LWS-N compiler will have to use tricks and techniques which are in some sense comparable to those used here.
Note the conventions used by this woodcutter to suggest shape and texture, conventions which vary from woodcutter to woodcutter. Conventions which we get to know and which the brain somehow integrates into our seemingly seamless subjective experience. So in the figure above we have conventional markings suggesting the roundness of the poles supporting the roofs of the barns, and other conventional markings suggesting the leaves of trees and other plants. With neither convention being very close to what you might see in the real world or get from a photograph.
Note also that object relations in the two dimensional woodcut have to be coded in a different way to real life. Not least because small head movements here are of no help, they do not change the appearance of things here in the way that they do in real life.
Figure 14 |
The cockerel weather vane is reasonably clearly a cockerel, not a peculiar hole in a striped foreground object, even though the stripes on either side of the cockerel do not line up exactly. The eye does not notice this in normal viewing conditions. The white boundary serves to sharpen up the boundary, but at this magnification it does not seem to help in deciding whether we have a hole in the sky or a weather vane – in any event a white boundary which would not exist in real life.
Furthermore, the cockerel is in front of the tree to its left, albeit not very strongly. This must make use of the sequence cockerel sitting on roof of first building, first building in front of second building, second building in front of tree. And it may be we only get that sense when we are asked, or ask ourselves the question explicitly, when, in one way or another we put the brain to work on the question.
All of which works much better when the woodcut is viewed from a sensible distance, at a sensible scale. When the woodcut is taken in as a whole and the brain has all the information provided by the woodcutter to work on, not just the much small number of cues and clues it gets from a detail.
Figure 15 |
And even looking at the small portion at Figure 15 above, it is still a black object in front of a horizontally striped object, the white jagged boundary being more plausibly, more probably that of the black object than that of the striped object, from which it follows that the black object is in front.
The brain is bringing its knowledge of the real world to bear in its compilation, if we may use the LWS-N term, of the woodcut into the subjective experience of that woodcut. It is also making use of information about the whole in order to compile parts. So how does LWS-N – hypothesised to be self-contained – pull off a comparable trick?
Figure 16 |
Figure 17 |
Back to object relations in LWS-N
Figure 18 |
One thing we take away from the woodcuts, is that LWS-N is going to need some device or convention to express these object relations. And while we may be a bit shaky on distances and sizes, we do have strong perceptions of order and depth, we do have memories about either those objects in particular or objects in general, and LWS-N needs some device to express the relation in space, relative to the subject, of our two squares set against a background, complicated or otherwise, a relation derived from those perceptions and memories. The brain may use all kinds of clever cues, clues and algorithms to work those relations out, but what we need here is some way for LWS-N to express, to encode the answer, to project it into the subjective experience.
And for the moment we want to see what can be done within the confines of a single layer, within the confines of our (single) unit square, without supplements of the sort talked about at reference 7.
To this end, we suppose a world in which the nearer, more important things are in the middle of the scene, a world not unlike that of a proscenium arch theatre with wings on both sides, a backdrop, actors, actresses and other stuff arranged on the floor of the stage. Things of most interest tend to be in the middle of the scene. Possibly a rather simplified world, but note that we are only talking about the experience of a single frame of consciousness here, the experience of a second or so. If something else comes to be of most interest, the complier may well present a new frame. The parsimoniousness of consciousness of Chater of references 4 and 5 is relevant here.
We then suggest a rule in two parts. One: if objects A and B are close together, then if the primary frequency of A is greater than the primary frequency of B, then A is in front of B, is nearer the subject than B. Two: if we have two parts A and B of the same object C (for which the primary frequency will be the same), then if the secondary frequency of A is greater than the secondary frequency of B, then A is in front of B, is nearer the subject than B.
This does not exhaust two of our four parameters, our four degrees of freedom, but it does take a chunk out of them. There is less left to do stuff like colour and texture, which we shall, in any event leave to the next episode.
Figure 19 |
We have two objects in this experience, both of them made up of four parts, with a very modest amount of part overlap, bottom right. A background, with a fair amount of detail, but very much in the background. The left hand object has the high primary frequency, the right hand object has the medium primary frequency and the background the low. The left hand object is what we are focussed on, and it seems bigger than right hand object, whether or not it is in real life.
While the blue is high secondary frequency, green medium and red low, this giving us the spatial ordering of the parts.
Noting, once again, that this is the experience of a moment, of a single frame of consciousness. Rankings may move around a bit for the next frame.
Figure 20 |
Figure 21 |
We have a clear boundary between the two parts of the object upper right the figure above, but how do we resolve the ambiguity about which of the two parts is on top, is in front, from the point of view of the subject? In the figure, this resolution is more or less achieved by depth of colour, with the darker blue being presumed to be above the lighter blue, although it is still possible for the brain to flip from one orientation to the other.
But assuming that we solve this problem in the world of LWS-N, the possibility opens up of being able to see three dimensional objects in the round, albeit with less intensity and less detail in the occluded parts. And it seems quite likely that people will vary in the extent to which they are able to do this. I associate to an anecdote, I think from Glazer of reference 8, about a colleague who was able to rotate complicated crystal structures in her mind, a trick which he was not anything as good at.
Figure 22 |
Additional
A few oddments follow, slightly relevant to foregoing.
I went to a concert at the Wigmore Hall while preparing this post and got intrigued by the eight wires from which the two microphone clusters were hung from the ceiling. The small circular holes in the ceiling from which the wires emerged were clearly visible. The lower parts of the wires, the parts which seemed to catch the light, were clearly visible, although some wires seemed much fatter than others - which I thought an illusion rather than a fact on the ground, or rather a fact in the air. But the main point of intrigue was the way in which the upper parts of around half of the wires were invisible, despite the brain knowing perfectly well where they were. It did not see fit to make up for the deficiencies of lighting or eyes. It did not join up the dots.
The LWS-N hypothesis is that it is the organised firing of millions of neurons generates an electrical field which, of itself, amounts to the subjective experience of consciousness. Neurons such as those illustrated in Figure 1 above. But we say nothing about what else that firing may do, apart from being used to supporting that organisation. We say nothing about what outputs there may be or about where all the energy of all that firing goes.
I have also been thinking about the generation of the hypothesised electrical field. I recently read somewhere, perhaps at reference 3, about the potentials captured by EEG machines being more to do with charge running around dendrites, than the concentrated charge of an action potential running up an axon. It would be good to know more about what one might expect of a field generated by this complicated mass of neural tissue – but I don’t suppose that I ever will.
Furthermore, when talking of neurons, we have been thinking of a uniform population of neurons, all built the same say, all behaving the same way, all modelled in a tractable way by one set of equations, one set of rules, although we do allow individuality in the growth of dendrites and axons. There is no central ground plan for these. This may be an acceptable approximation, an acceptable simplification, but we need to bear in mind that that is what it is. In a population of a million neurons there is going be some damage and some turnover; neurons at the margin which do not come up to specification for one reason or another. Rather in the way that in a register of 50 million holders of national insurance numbers there are going to be some curiosities. Odd freaks of name, number or registration. Possibly left-overs from the past - even on computerised registers.
Figure 23 |
Conclusions
We have carried the story of our unit square of neurons onto the expression of objects, their parts and the relations in space between them. Hopefully the next episode will cover colour and texture.
Which will leave the less obvious business of supplementary information about visual objects, handled in the past by having supplementary objects on supplementary layers, linked to the visual objects by column objects, objects which perhaps serve to pass activation from one region to another. A sample of the previous treatment is to be found at reference 7.
References
Reference 1: http://psmv4.blogspot.com/2019/10/the-field-of-lws-n.html.
Reference 2: http://psmv3.blogspot.com/2017/03/on-seeing-rectangles.html.
Reference 3: Electroencephalography (EEG): neurophysics, experimental methods, and signal processing - Nunez, M. D., Nunez, P. L., & Srinivasan, R. – 2016.
Reference 4: The Mind Is Flat: The Illusion of Mental Depth and the Improvised Mind - Nick Chater – 2018.
Reference 5: http://psmv3.blogspot.com/2018/08/the-myth-of-unconscious.html.
Reference 6: Neuronal Oscillations in Cortical Networks - György Buzsáki, Andreas Draguhn – 2004.
Reference 7: http://psmv3.blogspot.com/2017/07/binding.html.
Reference 8: https://psmv3.blogspot.com/2017/04/bragg-and-son.html.
Reference 9: http://psmv3.blogspot.com/2018/01/an-introduction-to-lws-n.html.
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