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What intelligent machines need to incorporate from the neocortex
- computerex 9y agoFor those interested, Jeff Hawkins wrote a book called On Intelligence and he is largely the guy behind: https://en.wikipedia.org/wiki/Hierarchical_temporal_memory https://en.wikipedia.org/wiki/Hierarchical_temporal_memory Deep learning proponents focus on solving specific problems using mathematical models inspired by biology, whereas HTM proponents argue that biology is important and it should play a more central role. Deep learning folks are more geared towards applied AI, whereas HTM's are way more ambitious and are trying to solve the problem of intelligence/AGI. Numenta, the company behind HTM's has a platform called NuPic for "intelligent computing": https://github.com/numenta/nupic https://github.com/numenta/nupic But as far as I know HTM's have never been applied to anything non-trivial successfully.
- paladin314159 9y agoI recently read On Intelligence, very interesting take on the core principles of the brain. Perhaps someone more knowledgeable can comment on this, but it feels like deep recurrent networks do a pretty good job of capturing the concepts that Jeff Hawkins considers really important: hierarchy/invariance and sequences/prediction. Plus they're really effective in practice!
- computerex 9y agoThe concept Hawkins considers really important above all else is the biology. He rejects deep learning as being a fundamentally different form of computation than the one the brain performs. There are are no parallels to be drawn between RNN and HTM's, really. Apples and oranges. HTM's goal is literally to try and emulate the neocortex.
- etiam 9y ago"Emulate the neocortex" is at best a metaphoric shorthand that will be misunderstood by many, and quite likely the wrong way of thinking about it. It is certainly not to be taken literally. There are plenty of things going on in a real neocortex that are not essential to intelligence and Numenta was working hard from the start to pick out the important ones at an appropriate level of modeling. This distinction becomes especially important in contrast to things like Henry Markram's projects, where people seem to be happily spending major-multi-million-euro sums of public funds to run poorly understood simulations with insufficient detail on a really big computation cluster. RNN:s are crude compared to the HTM as well as to the more recent CLA model, but they do share for instance the formulation as a dynamical system with recurrence. Some of publications coming from people at Numenta have made direct comparison between the CLA to for instance LSTM-based networks, and in my opinion they are entirely reasonable to do that. They are all suited to sequence modelling. Having said that, I agree the comparison to RNN:s isn't to be made without understanding some of what goes into the HTM or CLA, and I agree that Hawkins emphasizes biological intelligence.
- ghthor 9y agoThey built a infrastructure monitor using the HTM https://grokstream.com https://grokstream.com Also http://www.cortical.io http://www.cortical.io is pretty dann cool.
- meri_dian 9y ago>"Intelligent machines don’t have to model all the complexity of biological neurons, but the capabilities enabled by dendrites and learning by rewiring are essential. These capabilities will need to be in future AI systems." This is the fundamental challenge that we face. Our ability to build AI that can emulate human thought is not limited by a poor understanding of the brain. Our current theoretical understanding of how human cognition arises from neural processes is probably close to a level sufficient to build human level AI. What limits our progress is the staggering computational demand of simulating a massive network of highly dynamic units. Shortcuts, simplifications and clever algorithms will only get us so far. At this point, processing power rather than theoretical understanding is the limiting factor.
- nabla9 9y ago>Our current theoretical understanding of how human cognition arises from neural processes is probably close to a level sufficient to build human level AI. This is not true at all. The brain of C. elegans (roundworm) has been mapped exactly (connectome is known) and we know it's 302 neurons and 8000 synapses well (it has just 959 cells total) but we still can't fully understand how its primitive brain works. It don't even have spiking neurons and it's still a mystery. It would be relatively straight forward to simulate. There is even software for doing it. To fully understand how even simple brain works, we must understand gene expression inside brain cells, role of somatic brain mosaicism inside brain, brain chemistry, neural connectome, how cortical columns work, neural coding, etc. When you get all this right, you need to fine tune it. Hyperparameter optimization for human level AI so that it's not epileptic, autistic, schizophrenic, manic, idiot or AI equivalent of these and million other things must be really hard process. --- http://www.openworm.org/ http://www.openworm.org/ http://bluebrain.epfl.ch/page-52741-en.html http://bluebrain.epfl.ch/page-52741-en.html http://cajalbbp.cesvima.upm.es/ http://cajalbbp.cesvima.upm.es/
- grondilu 9y agoThanks for reminding us of openworm. The fact that scientists are still working on simulating an animal with barely a thousand cells surely relativizes claims about simulating a mammalian brain, let alone a human one. Frankly, it's even kind of discouraging.
- danharaj 9y agoHow would one go about self-studying neuroscience to the level of say, a second year grad student not yet specializing in anything? That is to say, familiar with the basic concepts and able to make sense of current research given enough time.
- computerex 9y agoUdacity, coursera, edx, YouTube, Wikipedia, google should have you covered.
- bra-ket 9y agohttps://www.amazon.com/Principles-Neural-Science-Fifth-Kandel/dp/0071390111 https://www.amazon.com/Principles-Neural-Science-Fifth-Kande...
- return0 9y agoThat and Larry Squire's Fundamental https://www.amazon.com/Fundamental-Neuroscience-Fourth-Squire/dp/0123858704 https://www.amazon.com/Fundamental-Neuroscience-Fourth-Squir... are the bibles. Don't be intimidated by the size of the books they are actually easy to read.
- trextrex 9y agoWell it depends on which part you are interested in. The Neuroscience book by Mark Bear gives a nice introductory overview of the biology behind a lot of neural processes: https://www.amazon.com/Neuroscience-Exploring-Mark-F-Bear/dp/0781778174/ https://www.amazon.com/Neuroscience-Exploring-Mark-F-Bear/dp... If you're interested in computational neural models, I would highly recommend Wolfgram Gerstner's recent book (available for free online): http://neuronaldynamics.epfl.ch http://neuronaldynamics.epfl.ch The book by Dayan and Abbot on theoretical neuroscience is quite nice too: https://mitpress.mit.edu/books/theoretical-neuroscience https://mitpress.mit.edu/books/theoretical-neuroscience After this, you'll probably want to read new review papers, since it's a field that's moving quite fast now. (Especially with new measurement techniques in the past few years)
- Noseshine 9y ago
- amelius 9y agoAnd perhaps what the neocortex needs to incorporate from intelligent machines: backpropagation? I mean, so far we have no biological evidence of backpropagation, and it seems pretty useful.
- deleted 9y ago[deleted]
- bobosha 9y agoI have followed Hawkin's theory from its inception ca. 2005, since then they have been through multiple evolutions: from hierarchical bayesian models (with then collaborator Dileep George) and now an Sparse representation with Subutai. However, they have struggled with a "killer app". Barring some toy examples, very little by way of real-world use-cases.
- return0 9y agoRecently Matt Taylor from numenta had a reddit AMA (https://www.reddit.com/r/artificial/comments/6beeqj/5182017_1200_pm_pst_iama_with_matt_taylor_numenta/ https://www.reddit.com/r/artificial/comments/6beeqj/5182017_...). I was disappointed to find out that numenta does not really have collaborations with neuroscientists to test or adapt their theories. Their theories in general are not well known to computational neuroscientists either. In that sense, i m not even sure about the authority of numenta on neocortical theories. For example, the article mentions the ability of clustered synapses to act independently, but , on the one hand, it has been shown independent dendrites can be approximated as an extra neural network layer (so they ARE covered by today's ANN approximation) , and OTOH there s a number of papers showing that synaptic clustering does not exist in sensory areas. And learning by rewiring is basically the introduction of random connections which persist only if their weight increases enough (roughly corresponds the continuous formation of filopodia and the fact that large spines persist longer). Machine learning at the moment is an empirical science that has made great strides without consulting neuroscience for it. I think that has been a good thing: without having to bend towars some biological plausibility researchers have been more exploratory and creative, which has led to the creation of an empirical body of knowledge from which neuroscience could benefit in the future. OTOH, having watched the field of computational neuroscience there has not been a lot of progress since , basically the 80s. So i believe it would be best to leave each of the two fields go their own way.
- trextrex 9y ago> OTOH, having watched the field of computational neuroscience there has not been a lot of progress since , basically the 80s. So i believe it would be best to leave each of the two fields go their own way. I wouldn't really say that. There's a lot of progress being made in using and understanding biological processes for useful tasks. Not surprisingly, the biological mechanisms are surprisingly complex and rich and vary a lot through the brain (like you mentioned with the dendrites. Dendrites also work like coincidence detection mechanisms sometimes in some layers of the cortex [1] for instance) [2] gives a very nice overview of what is needed from both machine learning and computational neuroscience to solve the entire problem of understanding the human brain. There was the liquid state computing paper [3] in 2002 which showed that random networks of spiking neurons can perform some computations and have memory even in the absence of special learning rules. There has also been quite some work on understanding e.g. the role of assemblies of neurons (groups of neurons firing), assembly sequences, plasticity rules, theory formulating neural activity in a probabilistic manner, a better understanding of the role of inhibition, dendrites etc. And lastly, there have been huge advances in neuromorphic computing, both digital and analog. In some cases, the performance on these chips (that use spiking neurons) approaches that of state of the art machine learning. e.g. [4] [1] http://www.sciencedirect.com/science/article/pii/S0166223612002032 http://www.sciencedirect.com/science/article/pii/S0166223612... [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5021692/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5021692/ [3] http://www.mitpressjournals.org/doi/abs/10.1162/089976602760407955 http://www.mitpressjournals.org/doi/abs/10.1162/089976602760... [4] http://www.pnas.org/content/113/41/11441.abstract http://www.pnas.org/content/113/41/11441.abstract
- stefantalpalaru 9y ago> The neocortex stores these patterns primarily by forming new synapses. We don't know that. We have no plausible theory and no working model for biological memory storage. This whole article is jumping the gun. Before emulating the neocortex we'd need an understanding of how it works and we don't have one.
- gene-h 9y ago>Our discovery is that every region of the neocortex learns 3D models of objects much like a CAD program. Citation needed. If this was the case, certainly we'd have some experiments that show this? Especially since every part of the neocortex is supposed to be doing it. Now if we can make artificial neural networks that work with 3D data, learning such things as 3D data to value, 3D data to 3D data mappings that would be damn useful. IE, estimating how much it would cost to make something from a CAD model or how aerodynamic a thing is without running costly CFD. I'd also argue that we don't need 'truly intelligent machines' to "build structures, mine resources, and independently solve complex problems" Ants and termites are capable of doing similar tasks and I'm doubtful the author considers them 'truly intelligent'. >it should be possible to design intelligent machines that sense and act at the molecular scale. >These machines would think about protein folding and gene expression in the same way you and I think about computers and staplers. >They could think and act a million times as fast as a human. So if the author means in simulated environments, we are quite slow at simulating molecules. For molecular simulation, we need something like femtosecond(10^-15 s) time steps whereas each time step is on the order of milliseconds. We are trillions of times slower than realtime. This is for completely classical systems, if we take into account quantum effects, it's much longer. Oh and our simulation methods for such things are terrible. Intelligence would help here, but it's not going to be millions of times faster than a human. Now if they mean videoing what's happening with a microscope and learning from that, well the problem is we don't have a perfect microscope for seeing such things at the nanoscale. So in order to figure out what's going on we have to get creative and make tests for each thing we're trying to analyze. Now if the author means nanorobots inside cells doing learning and what not, just having such machines would be useful in and of itself. Heck if we could make such things, we wouldn't need to worry about problems such as gene expression or protein folding because we'd be able to make our own damn proteins or our own damn cells for that matter. Even with drexlerian tech doing this sort of machine learning at this scale is pretty ridiculous. Current nanobot designs require something on the order of kilobytes of memory[1]. In addition, gene expression, protein synthesis and folding are slow processes. Average protein synthesis time for eukaryotes is 2 minutes[1](eons as far as simulating these things is concerned!). So getting this data can't happen much faster than a human can think. [0]http://people.umass.edu/bioch623/623/Second.Section/7.%20CoT.Web.2.08.pdf http://people.umass.edu/bioch623/623/Second.Section/7.%20CoT... [1]http://www.rfreitas.com/Nano/Microbivores.htm http://www.rfreitas.com/Nano/Microbivores.htm
- andbberger 9y agonumenta makes my kook sense tingle... but Jeff Hawkins did found the Redwood Center for Theoretical Neuroscience (now part of HWNI), and for that I am grateful.
- taneq 9y agoYeah, the ratio of bold statements to demonstrated effectiveness seems a little high. And after all their talk about embodied sensorimotor whatnots, HTM doesn't seem that good for, well, actually doing things, compared with mainstream deep learning (eg. AI Gym stuff.) Also I don't get why their method cares about sampling rate. It just seems weird. > A data sampling rate from once per minute to once per hour, with the “sweet spot” being between once per minute and once every five minutes (faster velocity data can be aggregated or sampled as well)
- shahbaby 9y agoStrongly believe that if anyone is going to solve human level intelligence in our lifetime, it's going to be Numenta. 'But we can't even figure out worms!' - Worms are made up of neurons but they perform a different function from what the neocortex does so studying them is not like studying a simpler problem, it's studying an entirely different one. 'But ML can do X better!' - Unlike industry or academia, Numenta's primary goal is to figure out how the neocortex works, it's not about profit or publications. 'Biology contains details we don't need!' - Numenta's approach is not biologically inspired, it's more like biologically constrained. They avoid implementations that are functionally different from how the neocortex works. I would highly suggest reading On Intelligence to learn more.
- deepnotderp 9y ago"Unlike industry or academia, Numenta's primary goal is to figure out how the neocortex works, it's not about profit or publications." Numenta is literally a corporation...
- foldr 9y ago>Worms are made up of neurons but they perform a different function from what the neocortex does so studying them is not like studying a simpler problem, it's studying an entirely different one. Huh? Take your pick of creatures that display highly intelligent behaviour and have less complex nervous systems than humans. Insect navigation would be a good example. If we can't figure out the biological basis of that -- when in many cases we already have a good idea of what calculations are being performed -- then our chance of "solving human level intelligence" is zero.
- shahbaby 9y agoThe problem is in defining intelligence by behavior. What we see as intelligence in insects most likely originates from an entirely different process. Jeff talks about this exact issue in this speech he gave, 10 years go. He mentions it around the 11 min mark but the whole video is a great intro to what this is all about. https://www.youtube.com/watch?v=G6CVj5IQkzk https://www.youtube.com/watch?v=G6CVj5IQkzk
- theprop 9y agoSome professor asks students on the first day of neuroscience, if all there is to know about the brain is a mile long, how far have we gotten so far? Students guess a few yards, a hundred feet, ten feet...the professor says no no, not even 3 inches.
- mr_overalls 9y ago"The question of whether Machines Can Think... is about as relevant as the question of whether Submarines Can Swim." --Dijkstra (1984) The threats to computing science (EWD898).
- SAI_Peregrinus 9y ago"Machines won’t become intelligent unless they incorporate certain features of the human brain." How arrogant! The features they list aren't unique to humans, or even to mammals. They're all present in the nidopallium of birds as well. Machines won't become intelligent unless they incorporate certain features of intelligent life.