I saw a wonderful recording of a talk the authors gave a few years ago (which I regrettably can't find now), and it was amongst the most eye-opening talks I've ever seen.
It is sort of interesting… I think we will all admit that brains are more complex than computer chips. But I still wonder if there’s some general underlying principle that makes brains more reasonable to study in this fashion than computer chips.
For example, they talk about destroying one transistor, observing that the thing can’t play Donkey-Kong anymore, and concluding that that is the DK transistor.
But computer chips are designed to have incredibly long chains of dependencies where each specific transistor does exactly the right thing, every time.
For neurons, it isn’t so specific, right? They all might fire, depending on the timing, and whether or not they are… I don’t know biology, charged or whatever. The whole system works under the assumption that many complements will mis-fire or be duds are any moment.
It seems (to me at least) more reasonable, to come to the conclusion that the DK neuron is really a DK neuron, if removing it causes an un-recoverable DK related failure… because the whole system is based around handling failures! It is somehow special that something can break it.
Yes, there's more of a degree of redundancy in brains than microprocessors, but the 'lesion' approach tends to involve affecting more than just one neuron. The main point of that section is that you've got to be careful about what you define as a 'function'. In the processor case, if you defined function in terms of a register or instruction working properly, then this approach could actually give you a pretty good map. But if you've defined it as whether a particular game runs, it doesn't give you a good map at all, because most games exercise most functions of the microprocessor, and so which small parts aren't important to that particular game is only incidental. With brains the main thing is the underlying functions are not really known, so you need to approach with care.
I used to have the impression that the brain is more "mixed up" than it really is. It's quite hard to get the right impression as a layman. Experts push too hard towards the extreme that makes us think that everything is involved in everything and it's all thoroughly uniformly mixed, advising against believing those old naive brain charts etc. But really, certain functions are remarkably well localized. This kind of overcorrection is quite common if one often reads HN-like "well actually"-content, which is supposed to supplement a common perception with a small caveat. Beware of internalizing just the caveat and forgetting the main thrust.
Author of that paper here -- What an incredibly nice comment to wake up to at 3am, thank you! This paper made me quit neuro and switch to systems that are easier to model (small molecules) which it turns out are still annoyingly difficult!
I am always puzzled when biologists make analogies between living systems (or sub-systems) and human-designed devices (even complex devices). Human designed devices have an essential property that biological systems do not -- they were designed. While radios may seem complex, they are built from a relatively small number of component types with very well understood behaviors and typically limited numbers of interactions. Biological systems have no such constraints -- they were not designed, there can be many different ways to do the same thing (in the same cell), there are at least thousands, if not hundreds of thousands of different components, many of which have lots and lots of interactions. Considering how messy the systems are, it is quite remarkable that genetics and biochemistry discovered the basis of heredity (or at least some of it), the genetic code, hundreds of signaling pathways, etc etc. But there is no missing language, because there was no design that used that language.
As a CS graduate, I've always had a related inferiority complex towards "real scientists" like biologists, chemists, physicists who confront the real mess of reality, instead of our cozy self-made thought-castles as computer people. We live in a world where everything is intelligible in principle, if we take the time to dig into how it works; they live in a world of true mystery. However, I take consolation in the fact that seemingly CS can touch the esoteric and mysterious regarding computability and computational complexity.
Biological systems have also designs that emerged through evolution. Although the complexity may seem at different scales, the main difference is the measurements you can do. Both biological and electrical circuits are dynamic systems that have designs that gives them emergent functional properties.
As the article describes imagine having the list of radio components instead only instead of their topology (wiring diagram). The problem of figuring out how a radio works with this information, if youbknow little about their design, becomes quite similar with how figuring out how a biological system works.
The absence of a design diagram and our inability to measure components at the molecular level without disturbing the state of a system is the main reason bilogical systems are so challenging to understand.
I am a bit more comfortable saying "Biological systems also have 'solutions' that emerged through evolution." That is certainly true. But unlike designers, evolution is perfectly happy to re-invent the wheel (even if it is a less functional wheel). So different, evolutionarily independent, processes may provide the same solution, and of course solutions are constantly re-used to provide slightly different solutions. So I'm not sure that "complexity" is the hardest problem, though it certainly doesn't make things easy. The diversity of solutions for the same problem makes generalization/abstraction even more difficult.
Sure, but... how often do we object when fellow techies make analogies between just about anything and their field of expertise? We feel that our knowledge makes us quite qualified to explain the economy, to chime in on microbiology, and so on.
the two schematical views reminded me of a) the dualisms in Pirsig, and b) also of another similar one: two views of what-a-cat-consists-of - one according to the granny owner, and another according to the surgeon - but cannot remember which book was that from. Anyone?
Biology makes me thing if the universe/consciousness itself it's a product on information parsing itself, making that 'essence' or 'soul' (on how they defined it the Ancients) a truth beyond matter.
No, not something religious, but more related to computation.
But for this we should accept that 'data' it's an intrinsic part of Physics, not just matter.
I would like an intro to Thermodynamics, but IDK where to start.
The evolution approach is more like throwing spaghetti on the wall not design. The key event seems to “The Cambrian Explosion of Animal Life” which nature “ Experiment” body parts etc and see what is the best.
If a real biologist do it it will be like the evolution line approach which some thinks lead wu han lab created the covid funded by USA and approved by … That is debatable but the approach is not. Unless we can do evolve radio …
One must note bird seems to evolve use quantum mechanics to direct their migration. Hence that is not unthinkable.
The question is whether have radio communication has an evolution advantage. Ignore the issue of not science (as not refutable), that is the real question.
Or a recap from The Atlantic: https://www.theatlantic.com/science/archive/2016/06/can-neur...
I saw a wonderful recording of a talk the authors gave a few years ago (which I regrettably can't find now), and it was amongst the most eye-opening talks I've ever seen.
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