Researchers Get Neurons and Silicon Talking
Published: Jun 23, 2007
European researchers have created an interface between mammalian neurons and silicon chips, serving as the first crucial step toward development of advanced technologies that connect silicon circuits with a mammal’s nervous system.
Ultimate applications of the idea are limitless. It would probably, in the long run, enable creation of highly sophisticated neural prostheses to combat neurological disorders. It could also possibly be used some day to create organic computers that use living neurons as the CPU.
Such applications will be seen only after decades of research, however much nearer is the development of a technology that could enable highly advanced and sophisticated drug screening systems for the pharmaceutical industry.
According to Professor Stefano Vassanelli, a molecular biologist with the University of Padua in Italy, who is also a partner in the NACHIP project funded by the European Commission’s Future and Emerging Technologies commission, “Pharmaceutical companies could use the chip to test the effect of drugs on neurons, to quickly discover promising avenues of research.”
“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.”
NACHIP, with assistance from Ifineon, a German microchip company, placed 16,384 transistors and hundreds of capacitors on a chip just 1mm in size. The group had to find appropriate materials and the very topology of the chip had to be refined to make possible the connection with neurons.
Special proteins found in the brain are used to glue neurons to the chip. The proteins are more than a simple adhesive. “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.
These signals can be recorded using the chip’s transistors and neurons can also be stimulated through the capacitors. This enables the two-way communications.
The device was tested by stimulating the neurons and recording which ones fired using standard neuroscience techniques while tracking the signals coming from the chip.
The method has certain setbacks that the team hopes to improve in future projects. For example, the chances of the neurons getting damaged during the process is a major hurdle. A proposal to tackle the problems has been prepared. This includes matters such as how genes can be used to communicate with the neurons.
If NACHIP took the first crucial step towards a neuron-powered CPU, future work shall make way for a genetically-powered hard disk.
