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Consciousness is supported by near-critical slow cortical electrodynamics

pnas.org

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Re: Consciousness is supported by near-critical slow cortical electrodynamics

#41

Post by azeirah »

eightysixfour wrote: post #39
darawk wrote: post #20

Earlier quoted context omitted.

> I think all it would mean is that the human brain is non-deterministic. Chaotic systems are still deterministic. They're just extremely sensitive to their initial conditions/inputs.

I always find it interesting drawing the determinism line on chaotic systems. For example, is a chaotic system that depends on initial conditions so precise that having adequate measurement to predict the outcome would violate the uncertainty principle still deterministic?

As far as I understand it, determinism is about being able to predict the next state if you have all knowledge about a system.

That we can't have all knowledge about most systems in the real world doesn't mean they're not deterministic.

And who knows what kind of magical science we'll find in the future that turns everything we know about measurement upside down?

Re: Consciousness is supported by near-critical slow cortical electrodynamics

#43

Post by alan-hn »

awb wrote: post #12
colechristensen wrote: post #6

Earlier quoted context omitted.

Eh, not really. It's hard to describe features of chaos / nonlinear dynamics simply. There are features of chaotic systems that undergo phase changes from one type of behavior to another. Think a signal on one side of the transition to look like a pure sine wave and on the other side of the transition to look like purely random white noise. What these guys are reporting is that they found a parameter, a signal they c…

> It's also the kind of thing that can open a backdoor for free will in a deterministic universe, your brain in this chaotic state might behave deterministically but the actual state would never be knowable with enough precision to predict the outcome of inputs for any amount of time (butterfly effect). I think all it would mean is that the human brain is non-deterministic. That’s different from free will though whic…

I personally don't think that any macromolecular physical system can be entirely nondeterministic. We just don't understand how to make predictions for the system yet, but being beyond our understanding doesn't make it nondeterministic.

Re: Consciousness is supported by near-critical slow cortical electrodynamics

#44

Post by abeppu »

markhahn wrote: post #24

This strikes me as totally unsurprising. How could it be otherwise? It's basically saying that a brain normally operates in an interesting dynamical mode: not chaotic, and not very regular. Wow? If it were chaotic, we wouldn't have coherent or consistent behavior at any scale. If overly regular, we'd be incredibly dull and unable to respond to the environment. You could do this with a computer. If your signals coming…

I didn't read the whole thing, but I did find parts of it surprising.

Some things that jumped out at me:

> during conscious states, the electrodynamics of the cortex are poised near a critical point or phase transition and that this near-critical behavior supports the vast flow of information through cortical networks during conscious states

But we've had a lot of success building artificial systems that support a "vast flow of information" which I would expect are mostly nowhere near such a boundary. Stuff moves around within a periodic structure, and moving more info has corresponded to moving more information per period. Why would we not expect a pile of neurons with a ginormous number of connections to be able to move a lot of information even through largely periodic behavior?

> we found that the Lempel–Ziv complexity of the model’s simulated electrodynamics (with noise inputs) was maximal when the deterministic component of its dynamics were poised near this critical onset of chaos

I guess if the measure of "information richness" is based in compressibility of electrical activity ... is it surprising that it isn't higher in the chaotic phase? Why wouldn't one expect the chaotic system to produce as much or more random output?

Re: Consciousness is supported by near-critical slow cortical electrodynamics

#45

Post by colechristensen »

Buttons840 wrote: post #40
awb wrote: post #12

Earlier quoted context omitted.

> It's also the kind of thing that can open a backdoor for free will in a deterministic universe, your brain in this chaotic state might behave deterministically but the actual state would never be knowable with enough precision to predict the outcome of inputs for any amount of time (butterfly effect). I think all it would mean is that the human brain is non-deterministic. That’s different from free will though whic…

Deep philosophical discussions around free will can benefit from first defining what "free will" means.

Deep philosophical discussions around free will often consist entirely of defining what "free will" means.

Re: Consciousness is supported by near-critical slow cortical electrodynamics

#46

Post by croddin »

markhahn wrote: post #24

This strikes me as totally unsurprising. How could it be otherwise? It's basically saying that a brain normally operates in an interesting dynamical mode: not chaotic, and not very regular. Wow? If it were chaotic, we wouldn't have coherent or consistent behavior at any scale. If overly regular, we'd be incredibly dull and unable to respond to the environment. You could do this with a computer. If your signals coming…

A computer sending compressed or encrypted network traffic would look as if it were sending unexpected noise if you don't know how to read it.

Re: Consciousness is supported by near-critical slow cortical electrodynamics

#47

Post by tpfl »

netsharc wrote: post #7

It's a weird feeling to realize how we're all just hardware, and it might be possible to wake up someone who's "brain dead"/vegetative by LSD (the paper mentions how psychedelics affect this cortical electrodynamics, and as this old article[1] mentions the LSD). Imagine someone flipping a switch (in the future where tech to control the electrodynamics exists) and you're awake and aware of your surroundings again. [1]…

No post body was provided.

Re: Consciousness is supported by near-critical slow cortical electrodynamics

#48

Post by bjornsing »

markhahn wrote: post #24

This strikes me as totally unsurprising. How could it be otherwise? It's basically saying that a brain normally operates in an interesting dynamical mode: not chaotic, and not very regular. Wow? If it were chaotic, we wouldn't have coherent or consistent behavior at any scale. If overly regular, we'd be incredibly dull and unable to respond to the environment. You could do this with a computer. If your signals coming…

I had the same reaction. I wouldn’t be surprised if you could even formalize it and say that all information processing takes place on this edge between stability and chaos. That’s where all interesting/useful Turing machines live, for example.

Re: Consciousness is supported by near-critical slow cortical electrodynamics

#50

Post by unsui »

robbedpeter wrote: post #15
verisimi wrote: post #11

Earlier quoted context omitted.

"Think a signal on one side of the transition to look like a pure sine wave and on the other side of the transition to look like purely random white noise." This reminds me of something Rupert Sheldrake says is possible - that consciousness is 'off-site', that the body is more of a radio receptor.

There is no magic, nor room for it for any person that believes in the scientific method. There are a sufficient number of real mysteries and wonders not to waste time with pseudoscience. The brain is not a consciousness antennae, and there are no good reasons to think so. Consciousness is an emergent phenomenon entirely dependent on and contained within the brain.

agreed.

brain-as-a-radio-antenna is a common trope amongst those who would believe that meatspace isn't capable of generating consciousness alone (always looking for some sort of elan vital, to equate with another pursuit for the magic stuff of life).

From a purposely scientific perspective, we have to begin with the working assumption that materialism is true, until such point that it is conclusively proven false.

There is no evidence that the brain works in any way like an antenna, at least insofar as any electromagnetic waves or other such messaging systems supported by the physics of our current world as we know it.

Thus, the brain-as-antenna thinking necessarily pre-supposes an other-worldly explanation; it assumes what it's trying to prove.

Even if it were true (HIGHLY unlikely), we can't begin with that as the starting point in our search for understanding it. Otherwise, our brains are incredibly adept at shaping our thoughts and concepts to fit those prescribed notions of animacy and otherworldliness.

It's no wonder that many pseudoscientific principles BEGIN with the presupposition that you have to be willing to believe in order for the effect to become apparent.

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