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What the brain's wiring looks like

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Re: What the brain's wiring looks like

#62

Earlier quoted context omitted.

Because the brain is composed of physical matter which obeys the laws of physics.

> Because the brain is composed of physical matter Is consciousness?

Yes, the process that makes conciousness is also governed by physics.

Re: What the brain's wiring looks like

#63

Earlier quoted context omitted.

>There is no reason to believe, that we can't do this. A brain is part of our world, governed by physics. How do you know consciousness is "governed" by our contemporary understanding of physics?

It's unfortunate that you're being downvoted. This is a classic and unsolved problem in the philosophy of mind and the people stating confidently that of course the mind is a purely physical system are ignoring many problems with that hypothesis, not least the lack of any conclusive evidence for it.

Oh, yes, the lack of fine grained knowledge/easy understandable particle-physics allows for everyone to postulate the most fantastic theories into the percived gaps.

I for once believe that at the neuronal level, the sugar is spun into little pixies that fly around in the brain transfering information.

Dementia is occuring when somebody does no longer believe in fairys - and the little sugar elves die. So its always good to start any conversation on this with "I-do-believe-in-fairys" to keep the memory fresh.

Re: What the brain's wiring looks like

#64

Earlier quoted context omitted.

> Because the brain is composed of physical matter Is consciousness?

Yes, the process that makes conciousness is also governed by physics.

> the process that makes conciousness is also governed by physics.

How do you know that this is true?

Re: What the brain's wiring looks like

#65
post #33

Earlier quoted context omitted.

It's not a question of our contemporary understanding being sufficient to model a human brain. Rather it's that there is little or no reason to believe the brain and consciousness are pure unassailable magic. So it should be within the scope of future scientific understanding.

The brain and consciousness need not be magic for the philosophical issue to arise. The fundamental question is objectivity vs subjectivity. Consciousness is subjective, yet science is an objective affair. Can the objective be used to explain the subjective, or is the objective an abstraction from intersubjective experiences? If it's the latter, then the project to explain everything in scientific terms is doomed, be…

>The brain and consciousness need not be magic for the philosophical issue to arise. The fundamental question is objectivity vs subjectivity. Consciousness is subjective, yet science is an objective affair.

Pain is also "subjective", but we understand pain, who it develops and moves in the body, etc.

Plus, that consciousness is subjective is another way of saying we haven't mapped it specifically, so this is a kind of circular logic.

The "subjective" part is just a set of states of an objective construct (the brain, which is a physical object).

Re: What the brain's wiring looks like

#66
post #15

Earlier quoted context omitted.

> However, we will never be able to understand the thought process down to each individual activation of the neuron. Is that true in general, or are you specifically talking about human brains?

I mean a complex thought process. Like how to come from an activated retina cell to a movement to a part of a body. At time index 586578382342us the cell no 15547349 got activated which led to a slightly improved electric charge around the axon of neuron no 68342. The connection strength, as you remember, from time index 3870127106 is now 1% higher ..... one billion pages later ..... but the atom here is slightly mis…

Exactly - consciousness is clearly an emergent phenomena of these kinds (and possibly other kinds) of interactions in your brain due to the large scale.

In order to reason about the emergent phenomena, you have to "zoom out" - look at bigger pieces, not the individual atoms or neurons.

The tricky part here is that it seems that there is no particular reason for the bigger pieces to be separated into easy to reason about "modules". It could of course be the case, but I don't really see the evolutionary advantage between a "mess of wires" that works well enough and a system that is modularised.

So, if the brain is a modularised system, then there is hope of understanding it, as you can understand a computer that another commenter mentioned as well.

But, if not, then it might be the case that indeed a human brain will not be able to understand it by itself. If there is an underlying structure that's just intermixed with the other parts, then perhaps with the help of computers we can separate them logically.

There is of course the possibility that modularisation is simply not possible, because of (almost) full connectedness and interactions. Mr Penrose for example suggests the case of quantum entanglement leading to consciousness and if that really is the case, then there is essentially no way to "understand" why a certain decision was reached by the brain.

Re: What the brain's wiring looks like

#67

Earlier quoted context omitted.

Yes, the process that makes conciousness is also governed by physics.

> the process that makes conciousness is also governed by physics. How do you know that this is true?

Because, as far as we can tell, everything that is part of our universe is governed by physics.

Our brains are part of this universe, and conciousness is dependent on our brains.

Re: What the brain's wiring looks like

#68
post #57

Earlier quoted context omitted.

It's unfortunate that you're being downvoted. This is a classic and unsolved problem in the philosophy of mind and the people stating confidently that of course the mind is a purely physical system are ignoring many problems with that hypothesis, not least the lack of any conclusive evidence for it.

Can you really have conclusive evidence for "there is no magic"?

Don't ask people to prove a negative.

Re: What the brain's wiring looks like

#69

Earlier quoted context omitted.

Yes, the process that makes conciousness is also governed by physics.

> the process that makes conciousness is also governed by physics. How do you know that this is true?

What's the alternative?

Lets assume there is some sort of physical process involved that we don't understand or even know about (unlikely), it would still be part of the physics that govern our universe.

Re: What the brain's wiring looks like

#70
Just to clarify, MRI scanner at Cardiff is Siemens Connectom A, a specialized research 3T MRI scanner for which the main designs were part of Human Connectome Project.

It is not exactly "hot news", as it is already in research use for several years already (in the US, at MGH). It is, still, however, pretty unique in a way that it was optimized for human in-vivo diffusion MRI (tracing of white matter pathways in alive human subjects :-).

Diffusion MRI scans which can be obtained by this scanner are of exceptionally high quality and resolution (spatial and angular), and contain lots of data that can be fed to mathematical models to infer fiber crossings, etc.

However, despite the high spatial and angular resolution it is still at least an order of magnitude short of what is necessary to capture local axonal connections and this type of imaging certainly does not tell you the direction the signal is flowing.

Still an important progress IMO.

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