Seeing red

[emjay]

You will be surprised to find, maybe, that in the context of talking about brain and mind, I doubt there are any experiences we have that don't have some neural correlate.  Keep in mind that this is throwing out skepticism about the source of experiences, etc., which we've already probably talked about enough.

I'd like to list a few possibilities for consideration, not all (maybe not any) which are my own ideas.

First of all, let's start with the assumption that there's a physical universe, and that mind is exclusively a product of brain function, or at least of properties or functions of material in the brain.  Even given this, there are many levels upon which mind could supervene.  Let's list out a few of these levels just for hoots.

1)  Experience only supervenes through the coordinated effort of at least several brain parts.  Perhaps you need at least enough input to determine patterns, you need an organ capable of measuring events through a sense of time, etc.  Without all these components, you can't have anything said to be remotely conscious.

I just don't look at it at that level, but rather the network as a whole. So although neuroscience may identify/map different functional areas of the brain - and long may it continue to do so... by the different types of neurons, structure, and connectivity... they are ultimately all interconnected. Except for say split-brain patients where the corpus callosum that connects the two hemispheres of the brain is severed, leaving two networks, and no surprise for me given my theories, at least the appearance of two separate consciousnesses.

2)  Experience supervenes whenever certain brain parts (say the visual cortex) receive sufficient stimulation.  So if you stimulated a dead brain, little bubbles of "consciousness" would flash into that mental canvas for a moment despite the total lack of coherence of function in the brain in death.

Again, I see it at the whole network level rather than a specific function area. But that said, if hypothetically the visual cortex could be severed from the rest of the network it would still be a network in its own right. But it would be smaller and the connectivity would be different, at least pertaining to the rest of the - now hypothetically severed - network. So given my current theory, I would not necessarily expect the perception to take the same form as it does for the whole network... and that might depend on how the visual cortex is connected to the rest of the brain (which I'm afraid I don't know). If it was connected through a bottleneck as it were, like the corpus callosum, then I'd expect the perception to be similar (probably) because the states and relationships in the network would not be subject to that much outside interference, but if it was highly interconnected at every level in the visual cortex with far flung areas of the brain, then those additional relationships and states would change the overall constraints of the network, therefore different relationships and states would have to be differentiated in perception so I'd expect it to be different.

Regarding your second point, I fully agree and think something like could well happen. Basically, given input, a neural network 'settles' into a stable state of activation... that is to say first it's a kind of cascade of activation - as activation spreads through the network, with everything fluctuating, but eventually it settles down to a steady state of activation across the whole network. And given the connectivity in the brain it is possible for pockets of self-sustaining activity - in other words feedback loops - to exist, even once the input is turned off as it were. These little pockets are necessarily interconnected so they can be thought of as little mini networks for the sake of my theory. This is what I believe ideas to be - as in imagination/memory - with the vividness (where vividness just means different states represented) of the perception increasing the larger and more interconnected the pocket of activity becomes with additional input.

To be honest, the implications of this do give rise to genuine fears in me about what may happen during, and even after the death of the brain. There are safeguards in the brain to stop in getting over-excited - inhibitory neurons being one and 'neuron fatigue' which I don't know enough about but I believe would eventually cause a pocket of activation to stop. I don't know in enough detail about the physiology of the brain and how it is affected in the dying process. At a very rough level I know that neurons 'work' by allowing different types of ions from the 'extracellular space '(which has a similar make up to seawater) into the cell via passive channels and active pumps... and out of the cell in the same way, and that the purpose of these pumps etc is to create a potential difference across the membrane of the cell. But there it gets hazy for me because I don't understand electronics very well. But suffice it to say that the 'action potentials' of a neuron firing rely on the presence of these ions in the extracellular fluid. So one question for me is what happens to them after death? Then there's the pumps... they're not passive... they require energy so probably a neurons energy stores would run out. Then there's the neurotransmitters which I believe, though I'm not at all sure, receive their raw materials from the blood supply via some kind of transport molecules. But don't quote me on any of this... it's very very complicated and it's been a long time since I read anything about this in depth. But suffice it to say I don't know whether the brain could be stimulated after death... if the raw materials required for neural functioning would be present or for how long... nor do I know - and don't laugh - whether cremation could trigger neural activity... so I admit it is a worry (and perhaps an irrational one) that makes me seriously consider how I'd want to be disposed of after death. But nothing perhaps that a bit of dedicated study into the physiology couldn't solve.

3)  The essence of consciousness exists at a neuronal level-- this is the basis of perception, and every firing neuron has a kind of miniscule "awareness," although the person himself may not actually have access to it.  The conscious mind would be a kind of dynamic structure composed of billions of these tiny "idealets," if I can coin a word here.

I don't believe it's at the level of neurons, only networks. Ultimately a neuron is multi-purpose, and in my way of thinking not only can come to represent anything that it can detect, but can also represent more than one thing, though perhaps not at the same time. There are plenty of dendrites to go around so the same neuron could partake in different ways in different relationships. So I can't assign meaning to a neuron except through its relationships with others in the network.

4)  The most elemental "spark" of consciousness exists whenever information is exchanged, anywhere in the universe-- for example when a photon is absorbed with light information from a distant star by a receiving atom-- even if this is not part of an organism.  In this case, the cascade of information through electrochemical transmission in a single neuron would represent already a relatively massive corridor of "consciousness", though it would likely still be too insignificant to raise the conscious attention of a human being.

This is really where we came in isn't it... when I first met you guys? I kind of conflated yours and Rhythm's positions because they both relied on 'information' - which also appeals to me - though now I understand the difference between you. I admit it does hold an appeal and could even be the next logical step up from my theory in this thread in that I see consciousness as differentiating states and relationships and what is the universe but a helluva lot of different states and relationships?

I think the latter case is interesting.  It would mean that mind is intrinsic to all matter, not just special systems.  It would be the coordination of idealets into larger ideas, then concepts, and then a world view that WE would perceive as conscious awareness, much like only a gazillion particles working together can appear as a "thing" to us.

This would then eliminate the need to ask how mind supervenes on a physical brain.  Instead, all material interactions would be seen as mindful, with ours just being a unique case.

Let's try a reductio process here, because that's how I arrive at this idea.  Take a brain, and kill a single neuron.  Then another.  Then another.  What would happen?  Would there be a kind of critical mass, at which the brain would suddenly go into a coma?  Or would the quality of experience degrade imperceptibly but steadily, neuron after neuron, after neuron?  I suspect the latter, in which case not more than 2 neurons would be needed to support at least some kind of experience, although so primitive it would be almost quantum.

Given the choice, I'd say the latter, with the effect being as the result of each neuron removed reducing the complexity of the relationships and states to be differentiated in consciousness.

Now, let's take our 2 neurons, and start pulling molecules, 1 by 1.  Would there be a critical mass at which the neuron could no longer function, or would it gradually become less and less responsive?  Again, I suspect the latter.  I don't think any 1 particular pulled molecule would "turn off the lights," but instead you'd have shades of gray.  At some point, you'd have that structure which would allow the most minimal possible perception, though again I'd call it something like a "perceptling" or something like that to indicate its primitive elemental nature.

What, now, if you replaced the body of the neuron with wiring?  Would it still function?  One might suppose that so long as the emission and reuptake of neurotransmitters was possible, the method of transmission along the body wouldn't matter.  What now if you swapped out the synaptic mechanism with an electric mechanism, would it matter?  It's hard to see how, right?  So this would mean that a simpler system-- an electric wire-- should also be able to support the same elemental "perceptling."

Now we can go freaking nuts and continue pulling out metal molecules, maybe replacing them with fiber optics, or even just photons transmitting across a "synapse" of empty space."

Well, this is not really different than say a photon leaving the sun and being absorbed by an atom in a rock on Earth.

Sorry for the long ramble, but my point is this: without being able to determine otherwise, it seems to me that the most elemental structure capable of having some primitive perception would be a single body transmitting or receiving a photon.  In other words. . . mind is intrinsic to all matter, and matter is therefore not energy/matter, but energy/matter/mind.

This basically illustrates the problem with my theory. I go down to the level of nodes and relationships in a network, but no further. So from my perspective it doesn't matter whether the nodes are neurons, man-made chips, or implemented entirely in software; it's the states and relationships they represent that counts. But that therefore means that I've imposed my own abstract 'informational' layer between mind and matter that feels like it helps bridge the gap but doesn't really... it helps me understand it functionally and seems to correlate but it still doesn't bridge that gap. Because go low enough looking at a neuron... or anything else for that matter... and all you'll find is atoms in flux. So what is a neuron when it's representing a value? It is essentially just the flow of ions into and out of a cell. So looked at at that level the brain's neural network, in situ in the extracellular space is a maelstrom of activity with ions essentially being recycled as they move into and out of cells. Hard to pin anything down when looked at at that level. Likewise, relationships at that level just add synapses to the maelstrom.

So perhaps it is more like your theory where the states to be represented are not the abstract informational states in my intervening layer - which fails to bridge the gap - but the actual states of matter in the universe... and therefore as you say, energy/matter/mind. Something to think about