crossposted from advancednano.blogspot.com
Models of the brain built from specially designed computer chips could reveal the secrets of our cerebrum and are on the path to re-engineering the brain to enable the Singularity and could lead to transhuman enhancements. Kwabena Boahen, a neuroengineer at Stanford University, is planning the most ambitious neuromorphic project to date: creating a silicon model of the cortex. The first-generation design will be composed of a circuit board with 16 chips, each containing a 256-by-256 array of silicon neurons. Groups of neurons can be set to have different electrical properties, mimicking different types of cells in the cortex. Engineers can also program specific connections between the cells to model the architecture in different parts of the cortex.

"We want to be able to explore different ideas, different connectivity patterns, different operations in these areas," says Boahen. "It's not really possible to explore that right now." Boahen ultimately plans to build chips that other scientists can buy and use to test their own theories of how the cortex operates. That new knowledge can then be built into the next generation of chips.

"We can currently do small simulations of hundreds to thousands of neurons, but it would be great to be able to scale that up," he says.

The million-neuron grid will have a processing speed equivalent to 300 teraflops, meaning that unlike computer-software simulations of the cortex, the hardwired silicon model will be able to run in real time. "Instead of running a thousand software instructions, it's just current running through transistors, just like real neurons," says Boahen.

Engineers ultimately hope to use the information generated by the silicon cortex in a variety of ways--to build better neural prostheses, for example. "The real-time aspect of this technology allows us in principle to interface the silicon cortex with the real cortex or brain," says Gert Cauwenberghs, a neuroengineer at the University of California, San Diego. "There is the promise, at least in the future, to build a prosthesis to replace some lost motor function or sensory function."