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What the brain's wiring looks like

bbc.com

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Re: What the brain's wiring looks like

#91

Post by wu-ikkyu »

louithethrid wrote: post #85
jnicholasp wrote: post #64

Earlier quoted context omitted.

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

Whatever it is, it follows a deterministic ruleset, else there be madness. If it follows a deterministic ruleset, and we can observe it directly or indirectly, and write those rules down- theorize about those rules - we can allmost call it physics. If the feeling of beeing a clock, winds up a spring in the clock that works a mechanism that feels like fear on beeing predictable (aka exploitable) - that does not make t…

Quantum physics has thrown a wrench into the 17th century Newtonian theory of the universe being totally mechanical, like a game of billiards.

Re: What the brain's wiring looks like

#92

Post by jnicholasp »

Alain-lf wrote: post #67
jnicholasp wrote: post #64

Earlier quoted context omitted.

> 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.

> Because, as far as we can tell [...] conciousness is dependent on our brains.

This is neither a logical/mathematical proof, nor an empirically established fact. So how do you know? Why are you making statements of faith in what seems to be the scientific worldview, when the actual scientific worldview is that we should never make statements of faith?

Re: What the brain's wiring looks like

#93

Post by wu-ikkyu »

louithethrid wrote: post #63
wildmusings wrote: post #42

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.

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…

Is admitting that we do not know so uncomfortable that you must invent fairy tale strawman arguments to cover up our ignorance? Hubris is the antithesis of science.

Re: What the brain's wiring looks like

#94

Post by jnicholasp »

tazjin wrote: post #69
jnicholasp wrote: post #64

Earlier quoted context omitted.

> 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.

> Lets assume there is some sort of physical process involved

You're begging the question. Why is "some sort of physical process" the only hypothesis space you're considering?

Re: What the brain's wiring looks like

#95

Post by jnicholasp »

louithethrid wrote: post #85
jnicholasp wrote: post #64

Earlier quoted context omitted.

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

Whatever it is, it follows a deterministic ruleset, else there be madness. If it follows a deterministic ruleset, and we can observe it directly or indirectly, and write those rules down- theorize about those rules - we can allmost call it physics. If the feeling of beeing a clock, winds up a spring in the clock that works a mechanism that feels like fear on beeing predictable (aka exploitable) - that does not make t…

At the very bottom of physics, if we ever reach it with our observations and theories, there will be something that simply is, and is not explained by the interactions of some sub-system. The foundational elements of physics are probably non-conscious (assuming the currently known particles and fields are indeed non-conscious).

What grounds do we have for asserting as certain that consciousness is not a foundational thing-that-simply-is, but must definitely be composed from sub-systems that are themselves non-conscious?

Re: What the brain's wiring looks like

#96

Post by taneq »

vilhelm_s wrote: post #53
nwjtkjn wrote: post #51

Earlier quoted context omitted.

This might be naive, but I wonder if the essential part of mouse data could be compressed if only we understood it better.

The mouse genome is only 160 megabytes, and contains the instructions for building the brain as well as building everything else, so the "secret sauce" of how to make an intelligent brain should not be extremely large, once you figure out how to do it. :) A lot of the actual connections must be either random, or encoding things the mouse learnt while growing up.

The busy beaver of 1.6x10^8 can produce an awful lot of stuff.

Re: What the brain's wiring looks like

#97

Post by GolDDranks »

babyrainbow wrote: post #80
FeepingCreature wrote: post #72

Earlier quoted context omitted.

Is there any reason to doubt it?

Imagine the whole domain of physics to be P and our current knowledge to be a subset of it, P'. Is there any reason for the operations of brain to be limited to those involving P' only?

There is. It's called quantum field theory. QFT has the peculiar property that the interactions between elementary particles in it are symmetric in space and time. What that means, is that if an exotic particle is capable of interacting with some of the commonly known everyday particles, which we know the brain is made of, we are also capable of producing that exotic particle using our common, everyday particles. That means that if exotic particles exist, they interact with the everyday particles very weakly - otherwise we would've already produced them in the LHC.

That means that even if exotic particles existed, they wouldn't have a practical effect on everyday matter, and thus, to our brain.

This all, of course, lies on the assumption that the symmetry property of QFT is correct. It's very likely to be (at least in everyday conditions, such as in a slab of fat in 37 C heat bath) – after all, QFT is the most experimentally precise scientific theory ever discovered in the history of science.

Re: What the brain's wiring looks like

#98

Post by wu-ikkyu »

tux1968 wrote: post #33
wu-ikkyu wrote: post #27

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 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.

Define "magic". If we cannot understand something, does that make it magic?

Any sufficiently advanced technology is indistinguishable from magic.

Re: What the brain's wiring looks like

#99

Post by josefx »

dunk010 wrote: post #88
josefx wrote: post #86

Earlier quoted context omitted.

> whereas your code is an abstract entity designed to run on a rather simple analogue of a Turing machine. I cannot adequately put the insane laugh required as response to that into text form. So I will only write this and be just as right: going by physics the brain of a mouse can be adequately approximated by a perfect sphere.

I guess we'll all have to just imagine you're right, then. Mwahahaha!

The definition of a turing machine is mathematically perfect. No threading, no IO, no error correction, no errors, no asynchronous events, no processes fighting over shared resources, no resources that might or might not disappear at the blink of an eye, in short no nothing. In that it is equivalent to a spherical brain, any complexity relevant to the problem at hand removed.

Re: What the brain's wiring looks like

#100

Post by vilhelm_s »

dunk010 wrote: post #79
chongli wrote: post #77

Earlier quoted context omitted.

only 160 megabytes Take a bunch of source code. Compile it, obfuscate it, compress it, and encrypt it with AES such that the result is a 160MB blob. Now see how long it takes to figure out what it does, given a computer that costs a lot of money just to load your program and a long time to give you a result. The upper bound on the complexity of DNA as it relates to the complete expression of an organism phenotype is…

Most developers think of the genome like a big load of source code, and if only we could work out where the if and for statements were we could read it. This is an extremely naive and overconfident point of view; the analogy between source code and genomes is very poor. The genome is coding for proteins (by way of RNA). Those proteins are subject to all of physics (think: electrostatics, hydrophobics, ....), whereas…

It's true that genes and proteins is nothing like code, but in the context of understanding the brain, I think that should be cause for optimism, because it means that nature has its hands tied behind its back. The genes can't just contain a description of how the brain should be wired together, because the description also has to be "self-executing"; the entire object must robustly self-assemble just from proteins physically interacting. So although 700 megabytes of mouse genes could potentially contain a lot of stuff, it might be possible to do the same thing much more simply if we can program a digital computer instead.

Like, the connectome for C. elegans has been mapped out; it's can be written down as a 2 megabyte ascii text file. Just the connectivity is not enough to actually reproduce the behavior of the worm, you would also need data about the weight of each connection, but it's still a lot less data than the worm genome (about 25 megabytes---I hope I got the number right this time!). The worm genes also need to contain a lot of additional stuff to build functioning cells internals, etc, stuff which hopefully is irrelevant to the actual cognition.

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