SAN FRANCISCO (AP) -- Computers, like humans, can learn. But when Google tries to fill in your search box based only on a few keystrokes, or your iPhone predicts words as you type a text message, it's only a narrow mimicry of what the human brain is capable.
The challenge in training a computer to behave like a human brain is technological and physiological, testing the limits of computer and brain science. But researchers from IBM Corp. say they've made a key step toward combining the two worlds.
The company announced Thursday that it has built two prototype chips that it says process data more like how humans digest information than the chips that now power PCs and supercomputers.
The chips represent a significant milestone in a six-year-long project that has involved 100 researchers and some $41 million in funding from the government's Defense Advanced Research Projects Agency, or DARPA. That's the Pentagon arm that focuses on long-term research and previously brought the world the Internet. IBM has also committed an undisclosed amount of money.
The prototypes offer further evidence of the growing importance of ``parallel processing,'' or computers doing multiple tasks simultaneously. That is important for rendering graphics and crunching large amounts of data.
The uses of the IBM chips so far are prosaic, such as steering a simulated car through a maze, or playing Pong. It may be a decade or longer before the chips make their way out of the lab and into actual products.
But what's important is not what the chips are doing, but how they're doing it, says Giulio Tononi, a professor of psychiatry at the University of Wisconsin at Madison who worked with IBM on the project.
The chips' ability to adapt to types of information that it wasn't specifically programmed to expect is a key feature.
``There's a lot of work to do still, but the most important thing is usually the first step,'' Tononi said in an interview. ``And this is not one step, it's a few steps.''
Technologists have long imagined computers that learn like humans. Your iPhone or Google's servers can be programmed to predict certain behavior based on past events. But the techniques being explored by IBM and other companies and university research labs around ``cognitive computing'' could lead to chips that are better able to adapt to unexpected information.
IBM's interest in the chips lies in their ability to potentially help process real-world signals such as temperature or sound or motion and make sense of them for computers.
IBM, which is based in Armonk, New York, is a leader in a movement to link physical infrastructure, such as power plants or traffic lights, and information technology, such as servers and software that help regulate their functions. Such projects can be made more efficient with tools to monitor the myriad analog signals present in those environments.
Dharmendra Modha, project leader for IBM Research, said the new chips have parts that behave like digital ``neurons'' and ``synapses'' that make them different than other chips. Each ``core,'' or processing engine, has computing, communication and memory functions.
``You have to throw out virtually everything we know about how these chips are designed,'' he said. ``The key, key, key difference really is the memory and the processor are very closely brought together. There's a massive, massive amount of parallelism.''
The project is part of the same research that led to IBM's announcement in 2009 that it had simulated a cat's cerebral cortex, the thinking part of the brain, using a massive supercomputer. Using progressively bigger supercomputers, IBM had previously simulated 40 percent of a mouse's brain in 2006, a rat's full brain in 2007, and 1 percent of a human's cerebral cortex in 2009.
A computer with the power of the human brain is not yet near. But Modha said the latest development is an important step.
``It really changes the perspective from `What if?' to `What now?''' Modha said. ``Today we proved it was possible. There have been many skeptics, and there will be more, but this completes in a certain sense our first round of innovation.''
<한글기사>
인간 두뇌 닮은 컴퓨터 칩 개발
미국의 세계적인 컴퓨터업체 IBM이 1 8일 인간의 두뇌를 닮은 컴퓨터 마이크로 프로세서를 개발했다고 월스트리트저널 등 미국 현지 언론들이 보도했다.
이에 따르면 이들 칩은 256개의 전자 뉴런(신경세포와 돌기, 신경섬유 등으로 구성된 정보 전달의 기본 단위)을 가지고 있다.
중 한 칩은 26만2천144개의 프로그램이 가능한(programmable) 시냅스(신경세포, 즉 뉴런의 접합부를 가리키는 말)를, 다른 칩은 6만5천536개의 '학습(learning)' 시 냅스를 가지고 있다. 인간과 동물에서 학습과정은 두뇌 세포 간 시냅스의 연결을 만 들고 강화하는 것을 의미한다.
BBC는 IBM이 시냅스 프로세서가 어떻게 작용하는지 구체적으로 공개하지는 않 았지만 런던 소재 버크벡 대학의 리처드 쿠퍼 박사는 '가상 머신(virtual machine)'
을 이용해 뉴런 간 물리적인 연결을 모방했을 가능성이 크다고 설명했다.
IBM은 이 칩을 이용해 인간이 지각하고, 학습하고 반응하는 법을 매우 유사한 수준까지 모방할 수 있는데다 기존 시스템에 비해 공간과 에너지를 거의 필요로 하 지 않는 컴퓨터시스템을 구축하게 될 것이라고 설명했다.
실제로 IBM은 이를 이용해 100억개의 뉴런과 10조개의 시냅스를 가지고 있지만
1㎾의 전력과 2ℓ가 넘지 않는 부피를 가진 시스템을 구축하는 계획을 세워놓고 있 다.
IBM에서 이 프로젝트를 담당하고 있는 과학자 드하르멘드라 모드하는 "오늘날 컴퓨터는 우리와 함께 있고 사랑받고 있지만 우리는 (컴퓨터를) 가족 일원으로 만들 고 싶다"고 말했다.
모하드는 이 칩이 획기적인 것이지만 진정한 인지시스템은 7∼10년 뒤에야 개발 될 수 있을 것이라고 인정했다.
IBM은 이 계획에 미국 국방부 산하 고등연구계획국(DARPA)이 2천100만달러를 투 자하기로 했다고 전했다. (연합뉴스)
