By Ania Monaco, theinstitute.ieee.org
Scientists have been trying for decades to build supercomputers that can replicate the brain’s information-processing abilities. But it has not been easy.
Computers operate sequentially, with one or several cores executing a preprogrammed set of instructions. But the brain operates quite differently, with many interconnected neurons processing highly parallel information that’s distributed throughout the neural network. For years, researchers in the field of neuromorphics—which involves developing computer architectures that process information in a manner inspired by the brain—have worked on bridging this gap between mind and machine. Among them is IEEE Graduate Student Member Sam Fok.
Fok and Alex Neckar [shown above, left to right], both doctoral candidates in electrical engineering at Stanford University, are developers of a neuromorphic device called the Neurogrid. It uses silicon neurons that perform computations by mimicking the way biological neurons function. Neurogrid simulates 1 million neurons and 6 billion synapses—the interfaces between neurons—in real time. “Using different parameters in the differential equations yields different spiking rates, so we have control over the spike rate and can make it vary between 0 and about 1 kHz,” Fok says. The neurons spike—or fire electrical impulses—at an average rate of 10 times a second. That means the Neurogrid’s simulations rival those done by such supercomputers as the one used in the Blue Brain Project, an ongoing effort by the Brain and Mind Institute of the École Polytechnique Fédérale de Lausanne, in Switzerland, to create a synthetic brain by reverse-engineering a mammalian brain to the molecular level. However, Fok and Neckar’s machine uses a millionth of the power needed for Blue Brain. The two were awarded a US $100 000 Qualcomm Innovation Fellowship in June for their work.
“Neurogrid’s purpose is twofold: to learn how neural networks in the brain work and how to harness these networks for tasks at which the brain vastly outperforms computers,” Fok says. “While computers have far exceeded humans in many tasks, we’ve yet to see computers even come close to human performance in tasks as simple as walking around.” Fok hopes Neurogrid can help change that. The fellowship money will go toward advancing the machine with help from researchers at Qualcomm, who will mentor the two.
Back to News Directory