The human brain is far too complex, the biggest brain simulator built by IBM, run by a 147,456-processor supercomputer, can only reach the level of a cat’s brain.
This brain simulator was developed by IBM’s Almaden research center. It consists of 1.6 billion virtual neurons connected by 9 trillion synapses, which is almost a cell-by-cell simulation of the human visual cortex.
With all the massive components, over 150,000 gigabytes of memory and power consumption of over million watts, the simulator is only as good as a cat’s brain. But the achievement is much better than the smaller rat brain simulator that they made two years ago.
To simulate the entire human cortex, they need computing power that is 1,000 times faster than what they currently have managed, but this could only be achieved in about a decade from now.
via gizmowatch
on Fri, Nov 20th, 09
at 11:53 am
[...] 20. IBM’s biggest brain simulator works as good as a cat’s brain (only) [...]
BM’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