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by marmaduke 2518 days ago
> It's the most detailed and closest to reality way to simulate neuronal dynamics

Nope, you can keep going with the same logic: HH is just an approximatiin of the molecular kinetics and what you really need are the FEM models in 3D with all the protein pathways etc etc.

But this leads to an entirely intractable project. The science lies not in reproducing the exact neurons bug for bug, but keeping only the necessary details, within technical possibility, for explaining some observed phenomenon. LIF and AdEx neurons seem like a good compromise for neuromorphic hardware.

2 comments

the HH model is good enough to reproduce almost everything that is recorded from neurons (Thats why H & H got the Nobel prize after all). Even dendritic regenerative spikes are reproduced by such models. I think it's generally acceptable that one does not need to do molecular dynamics to recreate membrane voltages. LIF and AdEx are very crude approximations though (i.e. no dendritic spikes, no plateaus, impossible to use them to approximate compartmentalized calcium levels that induce plasticity). And if you go that route, you have to justify why they are a better choice than e.g. Izhikevich neurons or indeed just sigmoid units.
> I think it's generally acceptable that one does not need to do molecular dynamics to recreate membrane voltages

everyone draws the line somewhere, this is yours. Even we take this statement to be true, you still have metabolic networks changing transmitter concentrations, dendritic arbors evolving in entirely unidentifiable ways, etc. The goal of modeling is not to say that every detail is there, but ones relevant to account for specific feature of data.

While there is more detail that can be simualted, there is a vast very successful literature using compartmental models. Markram's work was the simulation of a cortical column with compartmental models anyway.
The problem with this of course is the necessary level of detail depends on the phenomenon: simulating seizure propagation is probably different from simulating emotions. For more complex tasks we have no clue what that level is.