Henry Markram has become famous as the creator of the world's most expensive brain simulation, but neuroscientists know him best for his pioneering experiments on synapses. Markram was one of the first to investigate the sequential version of Hebb's rule in a systematic way, by varying the time delay between the spiking of the two neurons when inducing synaptic plasticity. (Changes in the synapses, the connection points between cells. One scientist reduced Hebb’s rule to: “Cells that fire together, wire together.”) When I first heard Markram speak at a conference, I also encountered the chain-smoking and charming Alex Thomson, another prominent neuroscientist, who lectured about synapses with bubbling enthusiasm. She was in love with them, and wanted us to love them too. Markram, in contrast, came across as the high priest of synapses, summoning our awe and respect for their intricate mysteries.
In a 2009 lecture Markram promised a computer simulation of a human brain within ten years, a sound bite that traveled around the world. If you view the video of the lecture online, you might agree with me that his handsomely sculpted face looks a bit fierce, but his manner of speaking is gentle and inviting, with the quiet conviction of a visionary. He didn't sound so calm later that year. His competitor, the IBM researcher Dharmendra Modha, announced a simulation of a cat brain, after having claimed a mouse brain simulation in 2007. Markram responded with an angry letter to IBM's chief technology officer:
You told me you would string this guy up by the toes the last time Mohda [sic] made his stupid statement about simulating the mouse's brain.
I thought that ... journalists would be able to recognize that what IBM reported is a scam - nowhere near a cat-scale brain simulation, but somehow they are totally deceived by these incredible statements.
I am absolutely shocked at this announcement .... I suppose it is up to me to let the "cat out of the bag" about this outright deception of the public.
Competition is great, but this is a disgrace and extremely harmful to the field. Obviously Mohda would like to claim he simulated the Human brain next-I really hope someone does some scientific and ethical checking up on this guy.
All the best,
Markram didn't keep his indignation secret. He sent copies of the letter to many reporters. One of them blogged about the controversy with a story wittily headlined "Cat Fight Brews Over Cat Brain:”
The letter marked a new low point in Markram's relationship with IBM. They had started out allies in 2005, when IBM signed an agreement with Markram's institution, the École Polytechnique Féderále in Lausanne, Switzerland. The goal of the joint project was to showcase IBM's Blue Gene/L, at that time the fastest supercomputer in the world, by using it to simulate the brain. Markram called the project "Blue Brain;” an allusion to IBM's nickname, "Big Blue:” But the relationship soured when Modha started a competing simulation project at IBM's Almaden Research Center.
Markram tried to defend his own work by accusing his competitor of fakery. But actually he cast doubt on the whole enterprise. Anyone can simulate a huge number of equations and claim it's like a brain. (You don't even need a supercomputer these days.) What's the proof? How do we know that Markram isn't a scammer too?
His glitzy supercomputer should not distract us from a potentially fatal flaw of his research: the lack of a well-defined criterion for judging success. In the future, Blue Brain could be evaluated with the specific Turing test described earlier, but this test only becomes useful when the simulation approaches the real thing. These purported mouse and cat brain simulations are not even in the ballpark yet. No "Mouse-tin Guerre" is going to fool you any time soon. The Turing test [a test of computer intelligence] will tell us when we've reached our destination, but until that day comes, we need a way of knowing if we're going in the right direction.