Researchers Get Neurons And Silicon Talking

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Researchers Get Neurons And Silicon Talking

http://www.medicalnewstoday.com/medicalnews.php?newsid=40466

The ultimate applications are potentially limitless. In the long term

it will possibly enable the creation of very sophisticated neural

prostheses to combat neurological disorders. What's more, it could

allow the creation of organic computers that use living neurons as

their CPU.

Those applications are potentially decades away, but in the much

nearer term the new technology could enable very advanced and

sophisticated drug screening systems for the pharmaceutical industry.

" Pharmaceutical companies could use the chip to test the effect of

drugs on neurons, to quickly discover promising avenues of research, "

says Professor Stefano Vassanelli, a molecular biologist with the

University of Padua in Italy, and one of the partners in the NACHIP

project, funded under the European Commission's Future and Emerging

Technologies initiative of the IST programme.

NACHIP's core achievement was to develop a working interface between

the living tissue of individual neurons and the inorganic compounds

of silicon chips. It was a difficult task.

" We had a lot of problems to overcome, " says Vassanelli. " And we

attacked the problems using two major strategies, through the

semiconductor technology and the biology. "

With the help of German microchip company Infineon, NACHIP placed

16,384 transistors and hundreds of capacitors on a chip just 1mm

squared in size. The group had to find appropriate materials and

refine the topology of the chip to make the connection with neurons

possible.

Biologically NACHIP uses special proteins found in the brain to

essentially glue the neurons to the chip. These proteins act as more

than a simple adhesive, however. " They also provided the link between

ionic channels of the neurons and semiconductor material in a way

that neural electrical signals could be passed to the silicon chip, "

says Vassanelli.

Once there, that signal can be recorded using the chip's transistors.

What's more, the neurons can also be stimulated through the

capacitors. This is what enables the two-way communications.

The project tested the device by stimulating the neurons and

recording which ones fired using standard neuroscience techniques

while tracking the signals coming from the chip.

The development of the interface and chip are crucial for this new

technology, but problems remain. " Right now, we need to refine the

way we stimulate the neurons, to avoid damaging them, " says

Vassanelli.

That's one of the problems the team hopes to tackle in a future

project. Right now a proposal has been prepared which could tackle

this and many other problems, including how to communicate with the

neurons using genes.

" Genes are where memory come from, and without them you have no

memory or computation. We want to explore a way to use genes to

control the neuro-chip, " says Vassanelli.

If NACHIP took the first crucial step towards a neuron-powered CPU,

future work will pave the way for a genetically-powered hard disk.

" Europe is very well placed in this field of research, because it is

essentially a multidisciplinary field, and we have multidisciplinary

teams working on it, " says Vassanelli. " We also have the

infrastructure with institutes like the Max Planck Institute for

Biochemistry in sried, which is one of the world leaders in the

field. Europe should be very proud of these resources. It gives us

access to equipment and expertise that would be very hard to

replicate elsewhere. "