March 24, 2009
Brain On A Chip
Scientists from the FACET project have a working prototype of a 'brain on a chip' They are trying to answer the question, 'how does the human brain run itself without any software?'
The goal of the FACETS (Fast Analog Computing with Emergent Transient States) project is to create a theoretical and experimental foundation for the realisation of novel computing paradigms which exploit the concepts experimentally observed in biological nervous systems. The continuous interaction and scientific exchange between biological experiments, computer modelling and hardware emulations within the project provides a unique research infrastructure that will in turn provide an improved insight into the computing principles of the brain. This insight may potentially contribute to an improved understanding of mental disorders in the human brain and help to develop remedies.
The human brain is often likened to a computer, but it differs from everyday computers in three important ways: it consumes very little power, it works well even if components fail, and it seems to work without any software. Nobody yet knows, but a team within FACETS is completing an exhaustive study of brain cells - neurons - to find out exactly how they work, how they connect to each other and how the network can 'learn' to do new things.
Mapping brain cells
According to Karlheinz Meier, a physicist at Heidelberg University, "we are now in a situation like molecular biology was a few years ago when people started to map the human genome and make the data available. Our colleagues are recording data from neural tissues describing the neurons and synapses and their connectivity. This is being done almost on an industrial scale, recording data from many, many neural cells and putting them in databases."
Another group at FACETS is developing simplified mathematical models that will accurately describe the complex behaviour that is being uncovered. Although the neurons could be modelled in detail, they would be far too complicated to implement either in software or hardware.
The goal is to use these models to build a 'neural computer' which emulates the brain. The first effort is a network of 300 neurons and half a million synapses on a single chip. The team used analog electronics to represent the neurons and digital electronics to represent communications between them. It's a unique combination.
Since the neurons are so small, the system runs 100,000 times faster than the biological equivalent and 10 million times faster than a software simulation. "We can simulate a day in one second," Meier notes. A network is already being used by FACETS researchers to do experiments over the internet without needing to travel to Heidelberg.
Interacting with a neural computer will be different primarily since digital computers are built on principles that simply do not apply to devices modelled on the brain. To make them work requires a completely new theory of computing. "Once you understand the basic principles you may hope to develop the hardware further, because biology has not necessarily found the best solution."
Practical neural computers could be only five years away. "The first step could be a little add-on to your computer at home, a device to handle very complex input data and to provide a simple decision," Meier says. "A typical thing could be an internet search."
In the longer term, he sees applications for neural computers wherever there are complex and difficult decisions to be made. Companies could use them, for example, to explore the consequences of critical business decisions before they are taken. In today's gloomy economic climate, many companies will wish they already had one!
FACETS Website
Source: PHYSORG