One of the world's most powerful supercomputers has finally done what had seemed impossible: successfully modelled brain activity.
It would be an understatement to call the human brain complex. With over 100 billion neurons, its activity is so complicated that scientists and neurologists still don't really know precisely how it works. The brain is constantly adapting, changing and forging new connections — one million of them each second.
And, up until fairly recently, it was pretty difficult to study. It's only with the arrival of technologies such as functional magnetic resonance imaging (fMRI), electroencephalography (EEG) and functional electrical impedance tomography by evoked response (fEITER) that researchers have been able to gauge what happens in the human brain.
As for a computer that operates like a brain, that has always seemed like a science fiction pipedream. But we may be one significant step closer.
Researchers at Japanese research company RIKEN, the Okinawa Institute of Science and Technology Graduate University, and German research centre Forschungszentrum Jülich have used Japan's K computer — one of the world's most powerful supercomputers — to run the longest and most successful brain simulation to date.
Equipped with 705,024 processor cores and running at speeds of over 10 petaflops, it is ranked the world's fourth-most powerful computer. Using the Neural Simulation Technology (NEST) software and 92,944 of its processors, the computer managed to replicate one second of brain activity as it would play out across 1.73 billion nerve cells and 10.4 trillion synapses — only one per cent of the brain's neuronal network.
This took the K computer 40 minutes.
"The new result paves the way for combined simulations of the brain and the musculoskeletal system using the K computer," said Kenji Doya of the Okinawa Institute of Science of Technology, who is currently studying neural control of movement and Parkinson's disease. "These results demonstrate that neuroscience can make full use of the existing peta-scale supercomputers."
This project gives scientists hope for what the next generation of supercomputers — called exa-scale — might be able to do.
"If peta-scale computers like the K computer are capable of representing one per cent of the network of a human brain today, then we know that simulating the whole brain at the level of the individual nerve cell and its synapses will be possible with exa-scale computers hopefully available within the next decade," said project leader Markus Diesmann.