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Neuroscience Expert Dr. Henry Markram on the IBM “Cat Brain” Simulation: “IBM’s claim is a HOAX”

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Editors Note:   We’re hoping for more information from Dr. Modha who is also welcome to a Guest post here at Technology Report.

——   Guest Post by Dr. Henry Markram of the Blue Brain Project —-

IBM’s claim is a HOAX.

This is a mega public relations stunt – a clear case of scientific deception of the public. These simulations do not even come close to the complexity of an ant, let alone that of a cat. IBM allows Mohda to mislead the public into believing that they have simulated a brain with the complexity of a cat – sheer nonsense.

Here are the scientific reasons why this is a hoax and misleading PR stunt:

How complex is their model?
They claim to have simulated over a billion neurons interacting. Their so called “neurons” are the tiniest of points you can imagine, a microscopic dot. Over 98% of the volume of a neuron is branches (like a tree). They just cut off all the branches and roots and took a point in the middle of the trunk to represent a entire neuron. In real life, each segment of the branches of a neuron contains dozens of ion channels that powerfully controls the information processing in a neuron. They have none of that. Neurons contain 10′s of thousands of proteins that form a network with 10′s of millions of interactions. These interactions are incredibly complex and will require solving millions of differential equations. They have none of that. Neurons contain around 20’000 genes that produce products called mRNA, which builds the proteins. The way neurons build proteins and transport them to all the corners of the neuron where they are needed is an even more complex process which also controls what a neuron is, its memories and how it will process information. They have none of that. They use an alpha function (up fast down slow) to simulate a synaptic event. This is a completely inaccurate representation of a synapse. There are at least 6 types of synapses that are highly non-linear in their transmission (i.e. that transform inputs and not only transmit inputs). In fact you would need a 10′s of thousands of differential equations to simulate one synapse. Synapses are also extremely complex molecular machines that would themselves require thousands of differential equations to simulate just one. They simulated none of this. There are complex differential equations that must be solved to simulate the ionic flow in the branches, to simulate the ion channels biophysics, the protein-protein interactions, as well as the complete biochemical and genetic machinery as well as the synaptic transmission between neurons. 100′s of thousands of more differential equations. They have none of this. Then there are glia – 10 times more than neurons..And the blood supply…and more and more. These “points” they simulated and the synapses that they use for communication are literally millions of times simpler than a real cat brain. So they have not even simulated a cat’s brain at more than one millionth of it’s complexity.

Is it nonetheless the biggest point neuron simulation ever run?
No. These people simulated 1 billion points interacting. They used a formulation to model the summing up and threshold spiking of the “points” called the Izhikevik Formulation (an extremely simple equation). Eugene Izhikevik himself already in 2005 ran a simulation with 100 billion such points interacting just for the fun of it: (over 60 times larger than Modha’s simulation). This simulation ran on a cluster of desktop PCs and which every graduate student can run This is no technical achievement and certainly not even a record number of point neurons. That model exhibited oscillations, but that always happens so even simulating 100 Billion such points interacting is light years away from a brain.
see: http://www.izhikevich.org/human_brain_simulation/Blue_Brain.htm#Simulation%20of%20Large-Scale%20Brain%20Models

Is the simulator they built a big step?
Not even close. There are numerous proprietary and peer-reviewed neurosimulators (e.g., NCS, pNEURON, SPLIT, NEST) out there that can handle very large parallel models that are essentially only bound by the available memory. The bigger the machine you have available, the more neurons you can simulate. All these simulators apply optimizations for the particular platform in order to make optimal use of the available hardware. Without any comparison to existing simulators, their publication is a non-peer reviewed claim.

Did they learn anything about the brain?
They got very excited because they saw oscillations. Oscillations are an obligatory artifact that one always gets when many points interact. These findings that they claim on the neuroscience side may excite engineers, but not neuroscientists.

Why did they get the Gordon Bell Prize?
They submitted a non-peer reviewed paper to the Gordon Bell Committee and were awarded the prize almost instantly after they made their press release. They seem to have been very successful in influencing the committee with their claim, which technically is not peer-reviewed by the respective community and is neuroscientifically outrageous.

But is there any innovation here?
The only innovation here is that IBM has built a large supercomputer – which is irrelevant to the press release.

Why did IBM let Mohda make such a deceptive claim to the public?
I don’t know. Perhaps this is a publicity stunt to promote their supercompter. The supercomputer industry is suffering from the financial crisis and they probably are desperate to boost their sales. It is so disappointing to see this truly great company allow the deception of the public on such a grand scale.

But have you not said you can simulate the Human brain in 10 years?
I am a biologist and neuroscientist that has studied the brain for 30 years.  I know how complex it is. I believe that with the right resources and the right strategy it is possible. We have so far only simulated a small part of the brain at the cellular level of a rodent and I have always been clear about that.

Would other neuroscientists agree with you?
There is no neuroscientist on earth that would agree that they came even close to simulating the cat’s brain – or any brain.

But did Mohda not collaborate with neuroscientists?
I would be very surprised if any neuroscientists that he may have had in his DARPA consortium realized he was going to make such an outrages claim. I can’t imagine that that the San Fransisco neuroscientists knew he was going to make such a stupid claim. Modha himself is a software engineer with no knowledge of the brain.

But did you not collaborate with IBM?
I was collaborating with IBM on the Blue Brain Project at the very beginning because they had the best available technology to faithfully allow us to integrate the diversity and complexity found in brain tissue into a model. This for me is a major endeavor to advance our insights into the brain and drug development. Two years ago, when the same Dharmendra Mhoda claimed the “mouse-scale simulations”, I cut all neuroscience collaboration with IBM because this is an unethical claim and it deceives the public.

What IBM allowed Modha to do here is not only wrong, but outrageous. They deceived millions of people.

Henry Markram
Blue Brain Project


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