great idea in inviting Markram to your blog. Henry is actually a very welcome and frequent visitor at the center where Neurdon was born, CELEST. He points out a number of true statements (among which Eugene’s Izhikevich simulation in 2005 that, from the neuroscientific perspective, wes of a larger scale and more interesting that the current one).

I would like to take a step back from the controversy, though. I am not sure how much Modha’s statement has been, either on purpose or voluntary, distorted to fit various interests (IBM, reporters, etc). I have read the paper, and I was surprise to notice that the architecture chosen by Modha and colleagues to implement in C2 (described in Figure 1) is impressively similar to the one I published in 2008 in Brain Research, and started presenting in various conference in 2006. In fact, I recall talking to Modha about it in SfN in DC, I believe, in 2006!

I am therefore very familiar with the model and its limitations. I simulated a smaller scale of Modha’s architecture with Steve Grossberg to study how stable learning of synaptic connections can develop in the presence of STDP. I would love to see, if this is the direction that Modha is undertaking, their take on this essential and very complex issue.

Finally, I would like to point out that, despite I have to agree with Henry on the neuroscientific impact of the IBM work (not very big, I have to acknowledge), I think that the real value of the contribution is purely technical, namely…skip the first few pages and go read the details of their simulations. They successfully handled 147,000 processors, 144 terabytes of memory, by getting only a .3 percent deviation in workloads across cores. That, I believe, is the contribution of the work…. it sounds less sexy than simulating a cat brain!