Paper link: http://www.cell.com/abstract/S0092-8674(15)01191-5 for those who want to skip to it.

Abstract:

Highlights

•The Blue Brain Project digitally reconstructs and simulates a part of neocortex

•Interdependencies allow dense in silico reconstruction from sparse experimental data

•Simulations reproduce in vitro and in vivo experiments without parameter tuning

•The neocortex reconfigures to support diverse information processing strategies

Summary

We present a first-draft digital reconstruction of the microcircuitry of somatosensory cortex of juvenile rat. The reconstruction uses cellular and synaptic organizing principles to algorithmically reconstruct detailed anatomy and physiology from sparse experimental data. An objective anatomical method defines a neocortical volume of 0.29 ± 0.01 mm3 containing ∼31,000 neurons, and patch-clamp studies identify 55 layer-specific morphological and 207 morpho-electrical neuron subtypes. When digitally reconstructed neurons are positioned in the volume and synapse formation is restricted to biological bouton densities and numbers of synapses per connection, their overlapping arbors form ∼8 million connections with ∼37 million synapses. Simulations reproduce an array of in vitro and in vivo experiments without parameter tuning. Additionally, we find a spectrum of network states with a sharp transition from synchronous to asynchronous activity, modulated by physiological mechanisms. The spectrum of network states, dynamically reconfigured around this transition, supports diverse information processing strategies.

(somewhat biased) Background and context

A few years ago Markram was awarded around a bilion euros (maybe split across 2 projects?) to simulate a rat microcolumn, then a rat brain, and eventually a human brain. While the project had a cool goal and there was a team of really talented people behind it the neuroscience community largely panned the project. It was considered basically impossible, terribly unscientific, and cronyesque. It seems the project had gone off the rails source and that Markram might soon no longer be in charge.

Regardless of the drama, the above paper represents a MASSIVE scientific effort and makes some pretty substantial claims about what their simulation can do. Unfortunately, it's also 30 pages and not the simplest document ever produced. I do a little modelling and I'm having a hard time thinking through the claims.

Anyone who works in the cortical world have any thoughts about this paper? Is it a big step forward? Is the data presented in a way that is sane and accessible and can be used for further modelling? Do the claims of this paper make sense? Is the Blue Brain project being unfairly hounded? Is the BRAIN Initiative better designed?

(If anyone can't access the paper drop me a PM and I'll send you a copy)