Let's hope this takes over from research on live mice.

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Mouse brain simulated on computer

 

It takes a supercomputer to mimic a mouse brain

US researchers have simulated half a virtual mouse brain on a

supercomputer.

The scientists ran a " cortical simulator " that was as big and as

complex as half of a mouse brain on the BlueGene L supercomputer.

 

In other smaller simulations the researchers say they have seen

characteristics of thought patterns observed in real mouse brains.

 

Now the team is tuning the simulation to make it run faster and to

make it more like a real mouse brain.

 

Life signs

 

Brain tissue presents a huge problem for simulation because of its

complexity and the sheer number of potential interactions between the

elements involved.

 

The three researchers, James Frye, Rajagopal Ananthanarayanan, and

Dharmendra S Modha, laid out how they went about it in a very short research

note entitled " Towards Real-Time, Mouse-Scale Cortical Simulations " .

 

Half a real mouse brain is thought to have about eight million neurons

each one of which can have up to 8,000 synapses, or connections, with other

nerve fibres.

 

Modelling such a system, the trio wrote, puts " tremendous constraints

on computation, communication and memory capacity of any computing

platform " .

 

The team, from the IBM Almaden Research Lab and the University of

Nevada, ran the simulation on a BlueGene L supercomputer that had 4,096

processors, each one of which used 256MB of memory.

 

Using this machine the researchers created half a virtual mouse brain

that had 8,000,000 neurons that had up to 6,300 synapses.

 

The vast complexity of the simulation meant that it was only run for

10 seconds at a speed ten times slower than real life - the equivalent of

one second in a real mouse brain.

 

On other smaller simulations the researchers said they had seen

" biologically consistent dynamical properties " emerge as nerve impulses

flowed through the virtual cortex.

 

In these other tests the team saw the groups of neurons form

spontaneously into groups. They also saw nerves in the simulated synapses

firing in a ways similar to the staggered, co-ordinated patterns seen in

nature.

 

The researchers say that although the simulation shared some

similarities with a mouse's mental make-up in terms of nerves and

connections it lacked the structures seen in real mice brains.

 

Imposing such structures and getting the simulation to do useful work

might be a much more difficult task than simply setting up the plumbing.

 

For future tests the team aims to speed up the simulation, make it

more neurobiologically faithful, add structures seen in real mouse brains

and make the responses of neurons and synapses more detailed.