They have built a section of a brain that has 10K neurons and 30M connections between them and they claim all it is needed is to "just scale it". They might be able to scale the number of neurons to the right amount in the near future (many estimate the number of neurons in the human brain between 10G and 100G). But the biggest problem is the number of neuronal connections. Current estimates on the number of synapses in the human is around 10P (P for peta- i.e. 10^15). That doesn't sound as easy as "just scaling it up".
It seems most articles and discussions about the brain talk about the number of neurons and how to get enough processing power to simulate them, the way I see it, the bigger challenge is to be able to simulate the connections between the neurons.
That's 56 years of Moore's law. I think you're right that they'll have to do something other than scale up.
Luckily there's room for tons of optimization, especially if your goal is an AI instead of a medically accurate simulation of the brain. Simulations like Blue Brain will reveal the key features of neurons as they relate to computations performed by the brain. That will allow us to drastically simplify future brain models without losing accuracy, possibly even wiring them directly into hardware. I think it's plausible that this approach could yield a humanlike AI within 20-30 years.
Given that we currently have no testable hypothesis as to what is responsible for consciousness, but only speculations such as "it's an emergent behaviour", isn't Markram's assertion, "If we build this brain right, it will do everything ... I mean everything" a statement of blind faith?
I am all for this research, but I also wonder if we are not going down a blind alley, ignoring other possibilities that may well be testable.
I don't think it takes any faith to say that a sufficiently precise simulation of the physical characteristics of the brain would produce output similar to that of a real brain.
To the contrary; saying otherwise would require faith in new physics (some sort of "spiritual energy"?) that we have no evidence for at this time.
It seems most articles and discussions about the brain talk about the number of neurons and how to get enough processing power to simulate them, the way I see it, the bigger challenge is to be able to simulate the connections between the neurons.