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What the brain's wiring looks like
- dubrocks 9y agoFunny, it looks about as complicated as I would have imagined it.
- booleandilemma 9y agoJust wondering... How complicated does a brain have to become in order to understand itself? Could a brain exist that is so complicated that it could not understand itself, or does a brain's understanding always scale up with its complexity?
- livingparadox 9y agoThat very much depends on whether the complexity increases intelligence/comprehension or whether it is merely increased complexity.
- eanzenberg 9y agoRight.. There are brains larger than ours with less intelligence.
- 24gttghh 9y agoSuch as? We humans do colossally stupid things on a daily basis with our so-called intelligence.
- booleandilemma 9y agoJust in terms of size, elephants have larger brains than humans, and we are arguably more intelligent.
- deleted 9y ago[deleted]
- Razengan 9y agoTechnically, considering a long enough timescale, a brain is the Universe trying to understand itself.
- AnimalMuppet 9y agoDoesn't "try" imply intending? But the universe isn't a someone who can intend to do something. Your statement sounds like mysticism, trying to soften the emotional coldness of the materialist view of the universe.
- Razengan 9y agoThe space dust that coalesced into our solar system and planet eventually (picture it in fast-forward) became us and we "try" to understand stuff, no?
- AnimalMuppet 9y agoYes. But the space dust didn't intend to become us. It's something, not someone.
- Razengan 9y agoAre the neurons and chemicals and electrical impulses in our brains someone?
- xj9 9y agocollectively, yes. so the question is, where does the line between animate and inanimate lie?
- deleted 9y ago[deleted]
- Razengan 9y agoWhat about the brains of other animals or the nervous systems of insects, or the neurons in an octopus tentacle? Are they someone? It’s an interesting line of questioning. What makes “someone?” Is a living but braindead/comatose human body someone? Many may be inclined to say yes, yet a statue or other inanimate likeness of a human wouldn’t be considered someone.. How about a thing that doesn’t resemble a human at all but gives the exact same responses to inputs that a human brain would? Say, on a computer screen? If you were told that a real person is sitting somewhere and sending these responses, you’d say it was someone, but probably not if you were told that it’s an AI... It’s mostly all subjective and we just pick the definition that’s convenient for us to work with and comprehend.
- s-macke 9y agoYou should first define what actually means "understanding the brain" before you try to answer this question. Does "understanding of the brain" mean, that we can construct or simulate a brain? An artificial brain, which reproduce our intelligence and consciousness? There is no reason to believe, that we can't do this. A brain is part of our world, governed by physics. However, we will never be able to understand the thought process down to each individual activation of the neuron. That's like trying to "understand" and follow the movement of each atom in my coffee next to me.
- deleted 9y ago[deleted]
- criddell 9y ago> 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?
- s-macke 9y agoI 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 misaligned to its counterpart, ...... one billion pages later .... noise coming from dentride no 496839 .... one billion pages later .... let to a decreased potential at muscle cell no 9678402 and hence a millimeter shift of the finger tip no 3. ...... Do you want to here the exciting story about my semimenbranous muscle at time index 4386702121us :) Do we understand the brain when we have this information? What I want to say is, that our brain cannot store so much information and handle it. Hence, we cannot "understand" the brain on this level. ("The person did this, because .... ")
- giblaz 9y ago
- monster_group 9y agoQuestions such as these are tackled in the excellent book Infinity and the Mind [0]. [0] https://www.amazon.com/Infinity-Mind-Philosophy-Infinite-Princeton/dp/0691121273/ref=tmm_pap_swatch_0?_encoding=UTF8&qid=1499286076&sr=1-1 https://www.amazon.com/Infinity-Mind-Philosophy-Infinite-Pri...
- wakkaflokka 9y agoI love these types of books. I'm about to buy this. Is there any reason to get the most recent version (says "with a new preface by the author") over the $2 paperback?
- triplesec 9y agoYes. If the author is alive and you wish to reward their huge efforts and encourage them to write more of such books, buy them new.
- laythea 9y agoPut it this way. Our brains can't even answer that question.
- vinchuco 9y agoI remember hearing someone answer "if the brain was simple enough that we could understand it, it would be so simple that we wouldn't" to that question. Can a computer compute itself?
- booleandilemma 9y agoSo we can only understand the brain because it is complex. The brain may be the only object with this property.
- dredmorbius 9y agoIC design is largely a process of simulating and specifying the next generation of integrated circuits. So in the strict sense, not only can a computer compute itself, but it can compute its (more capable) successor generation. Practically, this now occurs in large server farms, so it takes a large number of computers to compute themselves and/or progeny. But this is very much what happens.
- alanbernstein 9y agoIt's fun to think that this is a sufficient definition of consciousness.
- anotheryou 9y agoLooks like any MRI. I did this from scans of my brain and than tried to follow the visual cortext to my eyes. I couldn't, because the scans only show the general direction water flows in, but the nerves behind the eye cross and at this point you can't tell what is just noise and what are interlaced nerves. Would be interesting to know how much better this model is.
- stefantalpalaru 9y ago> The scan shows fibres in the brain's white matter, called axons No. It shows the general direction of water molecules moving (mostly) outside those fibres. The end image is the result of some statistical processing of those vectors and some interpolation between "slices". So what we see has been influenced by fibres, but it's not actual fibres. It is very likely that much of the detail and branching was lost in the process.
- criddell 9y agoWhere is the neuron cell body? Would they be at the outside where the fibers (axons?) seem to terminate? I wouldn't have guessed that it would look so linear. I was expecting a much more tangled appearance.
- skndr 9y agoThe tangled part is actually mostly 2mm thickness on the surface[0]. That's why the folds matter so much: [0] https://28oa9i1t08037ue3m1l0i861-wpengine.netdna-ssl.com/wp-content/uploads/2018/04/Self-Reflected-in-violets-1.jpg https://28oa9i1t08037ue3m1l0i861-wpengine.netdna-ssl.com/wp-... Check out this article for a pretty cool overview of the brain: https://waitbutwhy.com/2017/04/neuralink.html https://waitbutwhy.com/2017/04/neuralink.html
- criddell 9y agoThank you! Great links.
- nacc 9y agoJust to clarify, these MRI images looks at white matter, which are mostly bundles of long-range myelinated axons. This is more likely a map of major highways in the brain (Or really the map of bundles of major highways in the brain, as MRI only has millimeter resolution). The connectome at the cellular level is massive. I think part of the mouse visual cortical connectome has been mapped out, and the data is on the order of tens of terabytes.
- leemailll 9y agoRetina has been mapped, visual cortex not likely
- aristidb 9y agoThe article indirectly says it's using special MRI machines with much better than millimeter resolution. So I think your first analogy is likely better than your second.
- undershirt 9y agoI think I remember reading that mapping an entire human connectome would require all the world's current storage capacity?
- nwjtkjn 9y agoThis might be naive, but I wonder if the essential part of mouse data could be compressed if only we understood it better.
- vilhelm_s 9y agoThe 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.
- nikki93 9y ago
- odreem 9y agoThe real challenge here is to understand the brain, and consciousness, without putting it in computer terminology. https://aeon.co/essays/your-brain-does-not-process-information-and-it-is-not-a-computer https://aeon.co/essays/your-brain-does-not-process-informati...
- JepZ 9y agoSorry, but the author of that article clearly does not understand... It doesn't matter if humans store data the way computers do, the point is, that humans can be abstracted as state machines. Yes, humans are certainly different than our PCs today, but that does not mean that the principles are so different. E.g. humans seem to use a lot of lossy 'compression' while that is something we try to avoid in software in recent years. So we use computers for the things humans cannot do very well and therefore it appears that we are different. I think the whole discussion about putting the human mind into computer terminology is more about accepting that humans are just biological machines versus believing that humans are special because they have a soul and are different than any other animal.
- goatlover 9y agoAlternatively, it's a seductive metaphor because humans love to try to explain one thing in terms of another. Thus the universe is like a clock, and the laws of physics operate like clockwork. Until QM and the metaphor broke down. Similarly, the brain is like a computer. Until it's not. Interesting how nobody runs it the other way. A computer is like the brain. Why don't we? Probably because we understand computers a lot better than brains, and use that analogy to make sense of something otherwise mysterious. None of this has anything to do with a soul, btw. It's all a matter of how we think about things. The mistake is when we take our metaphors literally and try to make domain B fit into domain A, despite obvious differences. Then we end up with a convoluted view of B that's been distorted by being mapped onto A.
- odreem 9y agoThe point, as I see it, is that we are trapped in our own paradigmatic understanding of the world, and use the most advanced metaphors we have at our disposal to conceptualize something that is still complex beyond our reach. Hilarity ensues years later when we see the body understood as steam pumps or engine valves etc (described by Zarkadakis in the essay). The challenge for us in 2017 is to not fall into the same trap and to understand consciousness in a deeper way that isn't through the lens of "wires, circuitboards, central processors, data, etc etc" Its enticing but it detracts from understanding the consciousness of all living things in a more advanced way. I am with you on your materialist presupposition, I just think we can do better. I think the de-simplification of these terminologies will actually lead to better augmented reality and better AGI.
- SemiTom 9y agoThe sheer scale of connectivity of the human brain boggles. An interesting read on neuromorphic computing's attempt to build systems informed by the biological brain https://semiengineering.com/neuromorphic-computing-modeling-brain/ https://semiengineering.com/neuromorphic-computing-modeling-...
- JepZ 9y agoIt's a tree ;-)
- dredmorbius 9y agoTrees aren't brains. Forests are brains.
- psyq321 9y agoJust 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.
- DrAwdeOccarim 9y agoIt says it's 7T in the article?
- psyq321 9y ago7T is the Nottingham University scanner. Cardiff is 3T Connectom A. These are different sites / scans in the article. In fact, 3T Connectom A is actually more optimized for Diffusion MRI / white matter tract tracing compared to the available 7T scanners due to its enormous 300 mT/m gradient. In theory, the best of both worlds would be a 7T+ scanner with ultra strong gradient system such as the one developed by the HCP team, but such device does not exist yet AFAIK.