> If we were that close to simulating a human brain there would be implementations up on github already

IIRC, the Blue Brain Project uses NEURON.

    hg clone http://www.neuron.yale.edu/hg/neuron/nrn

Indeed it does. If you want to see open source models of the brain check out: http://senselab.med.yale.edu/modeldb/ListByModelName.asp?c=1...

Being outside of academia, I am not privy to the historical reasons that modeldb is the way it is. Something about it has always bothered me.. why on earth are all of these models in different languages? I mean, these aren't exactly CPAN modules or metasploit modules. How are these supposed to be combined reliably? And what about unit tests? what is going on here?

Edit: oh, man :( http://rudylab.wustl.edu/research/cell/methodology/cellmodel...

http://senselab.med.yale.edu/modeldb/ShowModel.asp?model=642...

https://github.com/OpenSourceBrain/Thalamocortical/blob/mast...

last two lines are "sleep(5)" and "exit()" ... that's not how you do python modules :(

Expanding on neuroguy's comment, there's many different people working on making models and pretty much (<simplification>) the only things that matter here are the collections of transfer functions; given inputs, how do outputs propagate. You can see that in the C++ (well, C from the looks of it) example you gave, there's a time value, a timestep, a bunch of physical attributes, and a series of functions - no matter what the language or system used all the other models there have similar features.

When people look at the work of others they are less interested in the modelling system used and more interested in the model, which most are happy to translate to whatever system they are using as the very act of crawling through and translating from one form to another forces a certain kind of deeper look at the details.

It's on par with Watson & Crick using plasticine and paddlepop sticks for their model while others use ping pong balls and wire coat hangers ... further down the track everything gets unified but at the early stages one form of modelling is more or less as good as another.

It is for exactly this reason that the people of http://www.neuroml.org/ are doing their work. Good catch! To combine and place everything in one overarching language that can be used in any of the many Brain Simulators. There are many each with their own advantages, which is why there are so many different languages.

It would be worthwhile to get some more CS guys in the field. Agreed. Please join us :)