Dharmendra S. Modha

My Work and Thoughts.

Archives for 2007

“the power of possibilities overwhelms me more than the fear of misuse”

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Yesterday, your’s truly was quoted in CIO.com magazine in a beautiful article by Esther Schindler:

Dharmendra Modha, manager of cognitive computing at the IBM Almaden Research Center, believes that this transition is part of the next hundred years of technology leadership. The current data paradigm is structured data management, but in “real life” we deal with unstructured data (of which emotion is a single element). That is, we recognize a friend’s face no matter how she’s dressed or despite her mood; we detect patterns with a large amount of sensory data and we act appropriately. According to Modha, “We are at a crucial juncture in history where two trends are converging: the tremendous availability of computational power, and the amount of neuroscience knowledge that has exploded over the last few years.”

“Cognitive computing is about engineering the mind by reverse engineering the brain,” Modha explains. If the brain is the biological wetware, a collection of neurons and a set of interconnection between the neurons, then neuron by neuron and synapse by synapse, computer science is putting together the architecture of the mind. Thus, IBM Research is simulating collective dynamics; researchers are studying how a very large population of interconnected neurons evolve in order to characterize them mathematically and then to synthesize them for harnessing in synthetic computations. Says Modha, “Today, on a 4096 processor Blue Gene supercomputer with 256MB of memory per CPU, we are able to simulate 8 million neurons and 50 billion synapses, 10 times slower than real-time.” That’s just a start, but then the Cognitive Computing project is new. A mouse brain has 8 million neurons in one hemisphere and 64 billion synapses.

This research aims to assemble the knowledge to build novel perception machines, or novel sensory systems. Business issues, says Modha, will eventually involve visual recognition, pattern detection in the stock market, or inventory management in neurological devices—systems that underlie a wide variety of applications.

It’s all very blue sky, of course, as research is supposed to be. But those science-fiction computers-get-emotion stories spoke of both opportunity and horror. What dystopia do such researchers worry that they may unleash? Says Modha, “At this stage in science and technology, the power of possibilities overwhelms me more than the fear of misuse.”

Michael Arbib

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Yesterday, I had a privillege of hosting a Distingished Lecture at IBM Almaden Research Center by Professor Michael Arbib.

Professor Arbib lectured on “Modeling Mirror Systems on the Evolutionary Path to Language”.

Michael Arbib

Abstract:

We focus on the evolution of action capabilities which set the stage for the language-ready brain. Our framework is given by the Mirror System Hypothesis which charts a progression from a monkey-like mirror neuron system to a chimpanzee-like mirror system that supports simple imitation and thence to a human-like mirror system that supports complex imitation and language. We present MNS2, a new model of action recognition learning by mirror neurons of the macaque brain and ACQ, a model of opportunistic scheduling of action sequences as background for analysis of modeling strategies for “simple imitation” as seen in the great apes and “complex/goal-directed imitation” as seen in humans. The talk concludes by charting how this work may support models of the human brain’s capacity to process language.

A brief bio:

Michael A. Arbib is the Fletcher Jones Professor of Computer Science, as well as a Professor of Biological Sciences, Biomedical Engineering, Electrical Engineering, Neuroscience and Psychology at the University of Southern California, which he joined in September of 1986. He has also been named as one of a small group of University Professors at USC in recognition of his contributions across many disciplines.

Born in England in 1940, Arbib grew up in Australia (with a B.Sc. (Hons.) in Pure Mathematics from Sydney University), and received his Ph.D. in Mathematics from MIT in 1963. After five years at Stanford, he became chairman of the Department of Computer and Information Science at the University of Massachusetts at Amherst in 1970, and remained in that Department until his move to USC in 1986.

Arbib has published over 322 scholarly articles and is the author or editor of 38 books. His edited volume, The Handbook of Brain Theory and Neural Networks (The MIT Press, Second Edition, 2003) is a massive compendium embracing studies in detailed neuronal function, system models of brain regions, connectionist models of psychology and linguistics, mathematical and biological studies of learning, and technological applications of artificial neural networks. Most recently, Jean-Marc Fellous and he have edited Who Needs Emotions: The Brain Meets the Robot (Oxford University Press, 2005) while he has edited Action To Language via the Mirror Neuron System (Cambridge University Press, 2006).

He has received several honors: Chancellor’s Medal, University of Massachusetts at Amherst, 1982, Gifford Lecturer in Natural Theology, University of Edinburgh, Autumn 1983. Chancellor’s Medal, Syracuse University, March, 1989, Chaire d’Etat reservé des savants Etrangeres, Collège de France, Paris, May-June 1992, Socio Onorio, La Societa di Medicina e Scienze Naturali dell’Universitá di Parma, 1992, Fellow, AAAI, Lockheed Senior Research Award, USC School of Engineering, 1995, IEEE Neural Networks Council Pioneer Award for 1995, The Rouse Ball Lecturer for 2001, Faculty of Mathematics, Cambridge University, and Doctor of Science (Honoris Causa), University of Western Australia, September 14, 2004.

“Time past, time future intricately connected in the brain”

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A new study published in the Proceedings of the National Academy of Sciences establishes that "memory and future thought are highly interrelated and help explain why future thought may be impossible without memories." [1]

Abstract [2]:

"The ability to envision specific future episodes is a ubiquitous mental phenomenon that has seldom been discussed in the neuroscience literature. In this study, subjects underwent functional MRI while using event cues (e.g., Birthday) as a guide to vividly envision a personal future event, remember a personal memory, or imagine an event involving a familiar individual. Two basic patterns of data emerged. One set of regions (e.g., within left lateral premotor cortex; left precuneus; right posterior cerebellum) was more active while envisioning the future than while recollecting the past (and more active in both of these conditions than in the task involving imagining another person). These regions appear similar to those emerging from the literature on imagined (simulated) bodily movements. A second set of regions (e.g., bilateral posterior cingulate; bilateral parahippocampal gyrus; left occipital cortex) demonstrated indistinguishable activity during the future and past tasks (but greater activity in both tasks than the imagery control task); similar regions have been shown to be important for remembering previously encountered visual-spatial contexts. Hence, differences between the future and past tasks are attributed to differences in the demands placed on regions that underlie motor imagery of bodily movements, and similarities in activity for these two tasks are attributed to the reactivation of previously experienced visual–spatial contexts. That is, subjects appear to place their future scenarios in well known visual–spatial contexts. Our results offer insight into the fundamental and little-studied capacity of vivid mental projection of oneself in the future."

Links:

  1. News Article: http://www.physorg.com/news86928742.html
  2. Scientific Paper: Neural substrates of envisioning the future

RobotCub

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The following from the iCub website:

"RobotCub is a 5 years long project funded by the European Commission through Unit E5 "Cognition". Our main goal is to study cognition through the implementation of a humanoid robot the size of a 2 year old child: the iCub."

The following is the abstract of RobotCub paper:

"We describe a research initiative in embodied cognition that will create and exploit a 54 degree-of-freedom humanoid robot. This humanoid — RobotCub — is currently being designed and the final system will be made freely available to the scientific community through an open systems GNU-like general public licence. In addition, we describe a research agenda in cognitive systems that is based on the co-developmental learning through embodied physical interation: exploration, manipulation, imitation, and communication. This agenda borrows heavily from experience in developmental psychology and cognitive neuroscience. All cognitive software associated with RobotCub will also be available under the open systems licence."

“Coordinated Memory Replay in the Visual Cortex and Hippocampus During Sleep”

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A new article in Nature Neuroscience:

Abstract: "Sleep replay of awake experience in the cortex and hippocampus has been proposed to be involved in memory consolidation. However, whether temporally structured replay occurs in the cortex and whether the replay events in the two areas are related are unknown. Here we studied multicell spiking patterns in both the visual cortex and hippocampus during slow-wave sleep in rats. We found that spiking patterns not only in the cortex but also in the hippocampus were organized into frames, defined as periods of stepwise increase in neuronal population activity. The multicell firing sequences evoked by awake experience were replayed during these frames in both regions. Furthermore, replay events in the sensory cortex and hippocampus were coordinated to reflect the same experience. These results imply simultaneous reactivation of coherent memory traces in the cortex and hippocampus during sleep that may contribute to or reflect the result of the memory consolidation process."

See also the related News & Views article.