3 ms·
Those don't really work, though: http://lesswrong.com/lw/88g/whole_brain_emulation_looking_at_progress_on_c/ http://lesswrong.com/lw/88g/whole_brain_emulation_l
by streptomycin 14y ago
Those don't really work, though: http://lesswrong.com/lw/88g/whole_brain_emulation_looking_at_progress_on_c/ http://lesswrong.com/lw/88g/whole_brain_emulation_looking_at...
From the Human Brain Project http://www.humanbrainproject.eu/neuroscience.html http://www.humanbrainproject.eu/neuroscience.html
Why not begin with simple organisms like C.elegans?
There are two problems here. The first is feasibility; the second is the relevance of our results.
Feasibility. Neuroscientists have mapped all of C.elegans’ 300 or so neurons. However, enormous amounts of key data needed are still missing. For instance we do not have enough data on the physiology and pharmacology of C. Elegans neurons and synapses. And we still have limited data on the distribution of ion channels, receptors and other proteins on neurons, synapses and glia. Without this data we cannot build unifying models. A second problem is how easy it is to obtain the data. The crucial requirement for unifying models is the ability to access the data needed. Obtaining a deep understanding of the molecular machinery of a single neuron or a single synapse is just as difficult in C. Elegans as in human beings. And many datasets – particularly data on cognition - are actually easier to acquire in rodents, or even in humans. So we can’t just say: “let’s do this quickly in worms and do complex brains later”: we have to solve the same basic challenges, whatever brain we model. What we are actually doing is building a generic strategy we can use to reconstruct any brain.
Relevance: Studying the “simple” nervous systems of organisms like C.elegans or drosophila, is obviously very important, particularly for molecular and genetic studies. However the organization, electrophysiology and function of the mammalian brain are quite different. One of the HBP’s most important goals is to contribute to the development of new treatments for brain disease. But pharmaceutical companies already have great difficulties in translating results from mouse to human beings; with simpler organisms these problems become much worse. If we want to make a real contribution to clinical research, it is probably unwise to invest heavily in simple systems, so distant from the human brain.
- kanzure 14y agoI never claimed that the physiology of C. elegans should be preferred over that of the human brain.
- streptomycin 14y agoNo offense intended, I'm just trying to contribute to the discussion.
- tgflynn 14y agoIt sounds like they're saying 300 neurons is too hard so let's do 10^11 instead. Science usually proceeds somewhat incrementally from easier problems to harder problems and I'm not seeing the foundation here. Weren't simple genomes sequenced long before it was proposed to sequence the human genome ?
- neuroguy 14y agoThe argument is partially like that, but the more complete version is: 1) We know a lot about brain cognition through psychology, AI etc 2) We know a lot about how people process from all the years of expermentation. 3) The big things we don't know, is exactly what the role of the cell is, or how it processes. For example, is it they synchronous firing of cells that allows us to experience? What is actually going on in all those billions of cells etc. 4) We know a lot about the electrical activity in the brain, some about the molecular and chemical processes etc, but what we don't have is an overarching way of putting all this together, so we know what we are looking at. 5) We don't know what C. Elgans think about or what causes them to do things, so we will have a harder time understanding what exactly makes them tick. I apologize if there is repetition, unclear lines, or bad reasoning, I am in the middle of running some brain simulations, and had a minute while it ran.
- varjag 14y agoOn the other hand, activity patterns of C. Elegans neurons can be comprehensively studied, it's behavior is well studied in how it responds to simple stimuli. Simulating it has all the promising properties of good old scientific method. It is debatable whether building a $1.6B catatonic brain will advance neuroscience more than a comprehensive, experimentally matched simulation of a simpler system first.
- neuroguy 14y agoI don't think there is much debate about it. I think it is fairly obvious that this project will advance neuroscience quite a bit, even if it would be a smarter choice to start with the C. Elgans. A project like this, putting together what we currently know from experimentation is the necessary next step. Will it bring the massive game changing understanding of the brain that it is hoped, who knows.