Seeing red

[emjay]

And the question being what effect would that have on the system? It's an interesting question... what would it take to 'break' the neural network?

I wouldn't use the term broken.  Interference might break a digital system (it might not anyway), but the brain is what it is, and I wouldn't say that rare events would generally mean a "breaking."  I can imagine (and this is just speculation) that you could see epileptics as systems that are sensitive to constructive interference (i.e. harmonics), and that things like spiritual experiences might be, as well.

Yeah, not necessarily break but just drastically alter its functioning. I wonder now too if epileptic fits might be that sort of wave effect, and if so it's not a good thing. As for spiritual experiences, have you had any? Or what you'd liken to them? Ie in meditation. I haven't had any experiences that I would deem spiritual so I can't relate to it. But expert practitioners of meditation can 'quiet' the mind and experience all sorts of weird stuff. The point of meditation is to let thoughts and sensations float through your mind without being engaged as it were... so you're aware of them but you don't feed them. And that would fit in with what I've been saying about contexts, in that contexts are 'refreshed' by engaging with them, so perhaps what's going on in advanced meditation is that contexts are being allowed to weaken and deactivate... resulting in the equivalent of an empty mind And then there'd be the question of this feeling of connectedness that people report; a kind of at-one-with-the-universe/no-self feeling. But I have no ideas yet on that

Anyway, the point of all that was to hopefully understand what could go wrong if a butterfly effect, snowball thingy happened So I was thinking, since the neurons rely on maintaining very specific potential differences and concentration gradients relative to the extra-cellular fluid then I think it would be fair to say that the content of the extracellular fluid must be regulated just as much as it is inside neurons. And for that the blood-brain barrier springs to mind, because it requires active transport of nutrients that it allows through the barrier (which is not everything... not toxins in the bloodstream for instance) via special transport molecules/cells, whatever they may be. So the question is if you've got an edge case where say all neurons are either in the resting state or in the fully excited state, what would be the situation in the extracellular fluid?

That would be like having every start in the galaxy line up, I suppose.  

As for your question to both of us, about pulling neurons 1-by-1, I really don't know I'm sorry. I think a neural network will always find a way to represent whatever it can, depending on its connectivity, but with decreasing neurons and thus indirectly decreasing connectivity, the scope of the representations would reduce. But how to translate that into stable or variable I don't know... I think it would always be pretty stable whatever size it was but I don't really know what you mean.

I suppose my question is whether adding more members adds a statistical balancing force that will never be disrupted (like the QM particles in my table never "spiking" and causing it to light on fire or something), or whether the increased complexity adds to the chance of a rogue wave-type situation where SOMETIMES remarkable things will happen as a gazillion discrete events just happen to line up.

Okay I've just been reading about it, and I'll just put this out there. The cerebral cortex - that is the thin outer layer of grey matter that covers the cerebrum in all its characteristic folds... gyrus and sulci... which allows gives it more surface area - is made up of six layers of neurons with bidirectional connectivity as I've explained. Different parts of it handle different functions... visual processing... learning... motor processing etc, and have different concentrations of certain types of neurons in the different layers, but what's common to most of it is these six layers. And what's interesting, and what I didn't know until now, is that they're arranged in columns as per this image:

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...and that the difference between a human brain and any other mammalian brain is not the number of layers, but the number of columns. So the human brain has drastically more columns than any other animal brain, but the form of those columns is roughly the same in all mammals. So to the question of what would happen if you remove neurons one at a time, I'd say it depends where you remove them from, so if it was removing columns at a time in the cerebral cortex, I think the effect would be to reduce the representational space, and thus the complexity of the associations and the information processing that was possible.

It's fascinating and I really want to start understanding this structure intimately. The question is, am I willing to spend 75 quid on a book called Cerebral Cortex: Architecture, Connections, and the Dual Origin Concept? It's so tempting because my problem at the moment is I understand the principles and network dynamics of a generic network of that type and arrangement but I don't know much about the structure of specific brain areas. Maybe it's about time I did?