The human brain is the world’s most sophisticated computer, capable of learning new things on the fly, using very little data. It can recognize objects, understand speech, respond to change. Since the early days of digital technology, scientists have worked to build computers that were more like the three-pound organ inside your head.
Most efforts to mimic the brain have focused on software, but in recent years, some researchers have ramped up efforts to create neuro-inspired computer chips that process information in fundamentally different ways from traditional hardware. This includes an ambitious project inside tech giant IBM, and today, Big Blue released a research paper describing the latest fruits of these labors. With this paper, published in the academic journal Science, the company unveils what it calls TrueNorth, a custom-made “brain-like” chip that builds on a simpler experimental system the company released in 2011.
TrueNorth comes packed with 4,096 processor cores, and it mimics one million human neurons and 256 million synapses, two of the fundamental biological building blocks that make up the human brain. IBM calls these “spiking neurons.” What that means, essentially, is that the chip can encode data as patterns of pulses, which is similar to one of the many ways neuroscientists think the brain stores information.
“This is a really neat experiment in architecture,” says Carver Mead, a professor emeritus of engineering and applied science at the California Institute of Technology who is often considered the granddaddy of “neuromorphic” hardware. “It’s a fine first step.” Traditional processors—like the CPUs at the heart of our computers and the GPUs that drive graphics and other math-heavy tasks—aren’t good at encoding data in this brain-like way, he explains, and that’s why IBM’s chip could be useful. “Representing information with the timing of nerve pulses…that’s just not been a thing that digital computers have had a way of dealing with in the past,” Mead says.
TrueNorth comes packed with 4,096 processor cores, and it mimics one million human neurons and 256 million synapses.
IBM has already tested the chip’s ability to drive common artificial intelligence tasks, including recognizing images, and according to the company, its neurons and synapses can handle such tasks with usual speed, using much less power than traditional off-the-shelf chips. When researchers challenged the thing with DARPA’s NeoVision2 Tower dataset—which includes images taken from video recorded atop Stanford University’s Hoover Tower—TrueNorth was able to recognize things like people, cyclists, cars, buses, and trucks with about 80 percent accuracy. What’s more, when the researchers then fed TrueNorth streaming video at 30 frames per second, it only burned 63 mW of power as it processed the data in real time.
“There’s no CPU. There’s no GPU, no hybrid computer that can come within even a couple of orders of magnitude of where we are,” says Dharmendra Modha, the man who oversees the project. “The chip is designed for real-time power efficiency.” Nobody else, he claims, “can deliver this in real time at the vast scales we’re talking about.” The trick, he explains, is that you can tile the chips together easily to create a massive neural network. IBM created a 16-chip board just a few weeks ago that can process video in real time.
Both these chips and this board are just research prototypes, but IBM is already hawking the technology as something that will revolutionize everything from cloud services, supercomputers, and smartphone technology. It’s “a new machine for a new era,” says Modha. “We really think this is a new landmark in the history of brain-inspired computing.” But others question whether this technology is all that different from current systems and what it can actually do.
