Complexity Digest 2001.36

03-Sep-2001

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Content

  1. Are Music And Dance Credible Signals Of Coalition Quality?, Cogprints
  2. Investigating the Functional Anatomy of Empathy and Forgiveness, Neuroreport
  3. Intimidation Tactics May Have Led To Speech, New Scientist
    1. Pathological Laughter and Crying: A Link to the Cerebellum, Brain
  4. Learning Appropriate Contexts, CogPrints
  5. Neural Coding of Naturalistic Motion Stimuli, Network: Comput. Neural Syst
  6. Hypnosis Does Not Aid Memory Recall, Medscape
  7. Brain Cells Used to Make Working Semiconductor, Yahoo!/Reuters
    1. Nerve Chip Goes Live, Nature Science Update
  8. How Cells Find Their Way, The Scientist
  9. Experimental Robots `Learn' Right And Wrong, In The San Jose Mercury News
  10. The Arrival of Talking Computers and the End of Literacy, TNTY Futures
    1. What Happens When Machines Can Speak?, TNTY Futures
  11. Alter Our DNA Or Robots Will Take Over, Warns Hawking, Guardian
  12. Parasitic Computing, Nature
  13. Navy Uses Tiny Boxfish As Submarine Model, The Associated Press
  14. Self-Organization in a Surface Reaction: From Atomic to Mesoscopic Scale, Science
    1. Bridging Gaps and Opening Windows, Science
  15. Universal Behaviour In Compressive Failure Of Brittle Materials, Nature
  16. Superconductivity Race Heats Up, Science Now
    1. High-Temperature Superconductivity in Lattice-Expanded C60, Science
  17. Virus-Mediated Killing Of Cells That Lack P53 Activity, Nature
    1. Listening for Viruses, Science Now
  18. Principia Mathematica III, New Scientist
  19. The Emergence of Complexity: Science Coming of Age or Science Growing Old?, ChemWeb
  20. Links & Snippets
    1. Other Articles
    2. Announcements
    3. Conferences

  1. Are Music And Dance Credible Signals Of Coalition Quality?, Cogprints Next Article Bookmark and Share

    Summary: Numerous studies indicate that the human brain may contain neural specializations for music processing. This, in turn, suggests that there may be psychological adaptations for producing and processing music. If so, what function or functions did music serve in ancestral human environments? A variety of possible functions have been proposed, the most prominent being that music either promoted 'social cohesion' , or signaled mate quality. We propose, instead, that synchronization and variation, two universal features of music (and dance), are ideally suited to credibly signal coalition quality, a function that would have been critically important during alliance formation and war. Here we present the results of a small pilot study which supported this hypothesis. Subjects' perceptions of music quality were significantly correlated with their perceptions of coalition quality. A manipulation of music quality along a theoretically significant dimension was also significantly correlated with perceptions of coalition quality.

  2. Investigating the Functional Anatomy of Empathy and Forgiveness, Neuroreport Next Article Bookmark and Share

    Contributing Editor's Note: Previous functional brain imaging studies suggest that the ability to infer the intentions and mental states of others (social cognition) is mediated by medial prefrontal cortex. Forgiveness may be defined as ‘ceasing to feel angry or resentful towards another’comprising multiple cognitive components. Empathy and forgiveness are also both heavily dependent on the expression and interpretation of emotions. Little is known about the anatomy of empathy and forgiveness. In the following work, the authors undertake the study of human subjects and claim that this study is a first attempt to differentiate the neural correlates of these components. They propose the empathic and forgivability judgements activate specific regions of the human brain, which lead to social cohesion.

    Excerpt: Successful human social interaction (cohesion) requires understanding of other people's intentions and actions. The attribution of independent mental states to these others assists in explaining and predicting their behaviour. This attribution.. may be disrupted in some people with schizophrenia etc...We have used functional imaging to examine the neural correlates of making empathic and forgivability judgements.
    > ... these complex processes clearly implicate fronto-temporal brain regions and results suggest that attempting to understand others is physiologically distinct from determining the forgivability of their actions …abnormal mental states show differing patterns of activation.


  3. Intimidation Tactics May Have Led To Speech, New Scientist Next Article Bookmark and Share

    Excerpts: Men attempting to show off to their rivals in prehistoric times may have led to the evolution of speech. (...)

    A newborn baby's larynx resembles that of other mammals. It pokes up into the nasal passage like a snorkel, so babies can drink and breathe at the same time. But at three months old, the larynx descends, opening up a cavity behind the tongue.

    This was a vital step in the evolution of speech because it allows us to utter a much wider range of sounds.


    1. Pathological Laughter and Crying: A Link to the Cerebellum, Brain Next Article Bookmark and Share

      Abstract: Patients with pathological laughter and crying (PLC) are subject to relatively uncontrollable episodes of laughter,crying or both. PLC is a disorder of emotional expression rather than a primary disturbance of feelings, and is thus distinct from mood disorders in which laughter and crying are associated with feelings of happiness or sadness. PLC is due to the damage of pathways... the cerebellar structures that automatically adjust the execution of laughter or crying, operate on the basis of incomplete information about that context, resulting in inadequate and even chaotic behaviour.


  4. Learning Appropriate Contexts, CogPrints Next Article Bookmark and Share

    Abstract: Genetic Programming is extended so that the solutions being evolved do so in the context of local domains within the total problem domain. This produces a situation where different “species” of solution develop to exploit different “niches” of the problem – indicating exploitable solutions. It is argued that for context to be fully learnable a further step of abstraction is necessary. Such contexts abstracted from clusters of solution/model domains make sense of the problem of how to identify when it is the content of a model is wrong and when it is the context. Some principles of learning to identify useful contexts are proposed.

  5. Neural Coding of Naturalistic Motion Stimuli, Network: Comput. Neural Syst Next Article Bookmark and Share

    Contributing Editor's Note: The natural world presents complex, dynamic, non-repeated signals. In response to this, the behavior of sensory system of the brain is an important area of study. One tried and tested way to study such sensory information processing by the brain is to stimulate the sense organ of interest with physically appropriate stimuli and to observe the responses of a selected part of the system that lends itself to measurement. The following work is such an attempt with modified designs and methods to study motion-sensitive visual neurons in the fly.

    Excerpt: If the accuracy of information processing is limited by noise sources within the nervous system, we should observe a plateau, that is, information transmission should saturate at some defined level of input signal quality. …in principle we can surpass any degree of accuracy of the physical input signal by simply increasing the light intensity, and at some point the internal randomness of the brain’s components must become the limiting factor.


  6. Hypnosis Does Not Aid Memory Recall, Medscape Next Article Bookmark and Share

    Excerpts: Hypnosis does not improve people's ability to remember news events, but it does raise the level of confidence they have in their inaccurate memories, according to research presented here Sunday at the American Psychological Association's annual meeting.

  7. Brain Cells Used to Make Working Semiconductor, Yahoo!/Reuters Next Article Bookmark and Share

    Excerpts: German researchers have constructed the world's first semiconductor circuit that uses neurons (brain cells) from a living creature.

    ``This is the first direct functional interfacing of a living neuronal network with an electronic semiconductor chip,'' (...)

    Fromherz noted that a network of neurons from a snail were grown on a semiconductor chip and directly stimulated. (...) verified that an electrical signal traveled from the chip into the neuronal net, through the neuronal net, and back to the chip.


    1. Nerve Chip Goes Live, Nature Science Update Next Article Bookmark and Share

      Excerpts: "It has a touch of science fiction," admit the scientists who have wired up the first conducting nerve chip. The electronic circuit, grown from silicon and nerve cells, brings brain-repair chips, advanced biosensors and biological computers a small step towards reality.

      'Neuroelectronics' combines nerve cells and microchips. It could one day lead to 'neuroprosthetic' implants replacing damaged nervous tissue, and advanced computers mimicking living, learning circuits.(...)

      A stimulator beneath each nerve cell created a change in voltage that triggered an electrical impulse to travel through the cell.


  8. How Cells Find Their Way, The Scientist Next Article Bookmark and Share

    Excerpts: Organisms need to sense their environment. By sensing, they can develop, heal wounds, protect against invaders, and create blood vessels. Chemotaxis, or directional sensing, allows cells to detect chemicals with exquisite sensitivity. (...)

    These results show that cells are sensitive to chemoattractant uniformly located around their perimeters, which leaves the question unanswered of how do the cells know where the attractant is and in what direction to go. Experiments on both Dicty and neutrophils point the finger to membrane organization itself.


  9. Experimental Robots `Learn' Right And Wrong, In The San Jose Mercury News Next Article Bookmark and Share

    Excerpts: Weng is breeding a new kind of ``intelligent'' robot that learns in a novel way: by experience, the way animals and people do. He said this approach to learning will be cheaper, faster and more flexible than traditional robot-training methods, which are limited to what a human programmer tells the machine to do.

    Instead of stuffing its computer brain with elaborate instructions -- like Big Blue, the IBM chess champion -- Weng teaches his robot a few basic skills and then lets it learn on its own by interacting with its environment


  10. The Arrival of Talking Computers and the End of Literacy, TNTY Futures Next Article Bookmark and Share

    Excerpt: Over the next twenty years, VIVOs (voice-in/voice-out talking computers using visual displays but no text) will make reading, writing and text itself obsolete. Text/written language is essentially an ancient technology created 6,000 to 10,000 years ago for storing (by writing) and retrieving (by reading) information. VIVOs will perform this same storage/retrieval function more easily, efficiently, cheaply, and universally without requiring people to learn to read and write.

    By 2020, electronically-developed countries will be well on their way to becoming oral cultures.


    1. What Happens When Machines Can Speak?, TNTY Futures Next Article Bookmark and Share

      Excerpts: In the next 20 years, a machine will pass the Turing Test by speaking fluently in everyday language and appearing as intelligent as a human to all with whom it interacts. The point-and-click environment of today's PC will disappear. In its stead will be a simple everyday language interface (or "non-interface") based on prototypes being created today.

      Machines and humans will work together side-by-side, speaking to one another; (...) Rather than using monitors and keyboards, we'll simply speak to a microphone embedded in the wall, or to our enhanced wristwatches or lapels, receiving immediate, relevant responses in a modulated human voice.


  11. Alter Our DNA Or Robots Will Take Over, Warns Hawking, Guardian Next Article Bookmark and Share

    Excerpts: Stephen Hawking, (...), reignited the debate over genetic engineering yesterday by recommending that humans change their DNA through genetic modification to keep ahead of advances in computer technology and stop intelligent machines from 'taking over the world'.

    (...) Through this humans could 'raise the complexity of... the DNA [they are born with], thereby improving people'. He conceded the road to genetic modification would be a long one but said: 'We should follow this road if we want biological systems to remain superior to electronic ones.'


  12. Parasitic Computing, Nature Next Article Bookmark and Share

    Excerpts: [The authors show that the communication protocols on the Internet can be exploited] (...) transforming the Internet into a distributed computer in which servers unwittingly perform computation on behalf of a remote node. (...), we harness the power of several web servers across the globe, which-unknown to them-work together to solve an NP complete problem.(...)

    In summary, parasitic computing moves computation onto what is logically the communication infrastructure of the Internet, blurring the distinction between computing and communication. (...) Enabling all computers to swap information and services they are needed could lead to unparalleled emergent behavior, (...)

    • Parasitic Computing, Albert-Laszlo Barabasi, Vincent W. Freeh, Hawoong Jeong, Jay B. Brockman, Nature 412, 894 - 897 (2001)

  13. Navy Uses Tiny Boxfish As Submarine Model, The Associated Press Next Article Bookmark and Share

    Excerpts: Living in a rigid shell, unable to bend its body because its scales are fused together, the tiny boxfish looks like a cartoon character with its peculiar shoebox shape (...)

    [It]is the very model the U.S. Navy hopes to use to design a new miniature submarine that will scour the ocean bottom, operating efficiently even in turbulent waters.

    The sub could have myriad uses, whether to comb for underwater mines, conduct scientific research or hunt for wreckage from airplane crashes.

    "Fish are phenomenally maneuverable compared to anything that is man-made," (...)


  14. Self-Organization in a Surface Reaction: From Atomic to Mesoscopic Scale, Science Next Article Bookmark and Share

    Excerpts: Scanning tunneling microscopy data revealed the atomic processes in propagating reaction fronts that occur in the catalytic oxidation of hydrogen on Pt(111). The fronts were also characterized on mesoscopic length scales with respect to their velocity and width. Simulations on the basis of a reaction-diffusion model reproduce the experimental findings qualitatively well. The quantitative comparison reveals the limitations of this traditional approach to modeling spatiotemporal pattern formation in nonlinear dynamics.

    Spatiotemporal pattern formation in open systems far from equilibrium is the basis of self-organization of matter.


    1. Bridging Gaps and Opening Windows, Science Next Article Bookmark and Share

      Excerpts: (...) advanced surface science tools allow a catalyzed chemical reaction to be monitored in situ on the atomic scale while spatiotemporal patterns such as reaction fronts crossing the surface of a catalyst are observed under the same conditions on the micrometer scale. A gap between length scales several orders of magnitude apart is thus bridged. Systems of increasing complexity may be studied by adapting this approach.

      (...) Such patterns play a crucial role in catalytic processes but are difficult to understand in detail because of their complexity.


  15. Universal Behaviour In Compressive Failure Of Brittle Materials, Nature Next Article Bookmark and Share

    Excerpts: Brittle failure limits the compressive strength of rock and ice when rapidly loaded under low to moderate confinement. (...) Observations of compressive failure in ice suggest a mechanism whereby localization initiates owing to the bending-induced failure of slender microcolumns. (...) Our model predictions for both the brittle compressive strength and the brittle-ductile transition are consistent with data from a variety of crystalline materials, offering quantitative evidence for universal processes in brittle failure and for the broad applicability of the model.


  16. Superconductivity Race Heats Up, Science Now Next Article Bookmark and Share

    Excerpts: Researchers have combined two major surprises in 1980s physics--buckyballs (C60) and high-temperature superconductors--into one breakthrough. By placing a crystal of C60 spiked with other compounds in the heart of a transistor, they turned it into a superconductor, (...) at temperatures up to 117 kelvin (K).(...)

    Now, the team has found another way to increase the material's density of states: expanding the distance between individual C60 molecules in the crystal. (...) they found two, trichloromethane and tribromomethane, that more than doubled the superconducting temperature.


    1. High-Temperature Superconductivity in Lattice-Expanded C60, Science Next Article Bookmark and Share

      Excerpt: C60 single crystals have been intercalated with CHCl3 and CHBr3 in order to expand the lattice. High densities of electrons and holes have been induced by gate-doping in a field-effect transistor geometry. At low temperatures, the material turns superconducting with a maximum transition temperature Tc of 117 K in hole-doped C60/CHBr3. The increasing spacing between the C60 molecules follows the general trend of alkali-metal doped C60 and suggests routes to even higher Tcs [critical temperatures, Ed.].


  17. Virus-Mediated Killing Of Cells That Lack P53 Activity, Nature Next Article Bookmark and Share

    Editor's note: Cancer therapy often consists of invasive procedures that merely damage cancer cells more severely than healthy ones. Using viruses that can identify cancer cells by the absence of tumor-suppressor protein "p53" and then selectively induce apoptosis ("cell death") in those cells looks like a very promising alternative.

    Excerpts: A major goal of molecular oncology is to identify means to kill cells lacking p53 function. Most current cancer therapy is based on damaging cellular DNA by irradiation or chemicals. (...) We report here that adeno-associated virus (AAV) selectively induces apoptosis in cells that lack active p53. (...) Thus viruses can be used to deliver DNA of unusual structure into cells to trigger a DNA damage response without damaging cellular DNA and to selectively eliminate those cells lacking p53 activity.


    1. Listening for Viruses, Science Now Next Article Bookmark and Share

      Excerpts: (...) a vibrating quartz crystal coated with antibodies that bind a specific virus. The more virus particles attach to the crystal, the more its vibrations slow down (...)

      They first let particles of herpes simplex virus (HSV) attach to the crystal's antibodies, and then vibrate the quarter-sized crystal ever harder. All at once, the virus particles are thrown off. That shudders the crystal, which acts like a microphone and converts the vibration into an electrical signal. The size of the electrical peaks corresponds to virus concentration.


  18. Principia Mathematica III, New Scientist Next Article Bookmark and Share

    Editor's Note: This is from a Q&A session with complexity pioneer Stephen Wolfram about his new book "A New Kind of Science" that will be released later this year after two decades in the making.

    Excerpt: Suppose that the program for the Universe is four lines long. There's no room in those four lines to put in all the familiar stuff we know about space-time having four dimensions, the muon being 206 times the mass of the electron, and so on. Almost nothing from the everyday world will be obvious in the program. These things will have to emerge when the program runs. Figuring out how that works, and exactly what can emerge, can be arbitrarily difficult.


  19. The Emergence of Complexity: Science Coming of Age or Science Growing Old?, ChemWeb Next Article Bookmark and Share

    Abstract: The emergence of a new field of science called complexity theory has made an impact on the community of scientists as well as the general public. This brief tutorial takes a very special view of this. The thesis is that complexity science has grown out of a general lack of satisfaction with traditional scientific practices and their failure to find a way of capturing anything but a shadow of complex reality. In spite of the many impressive advances from science and technology, it is clear that the picture delivered of the world is that of a surrogate world populated by machines and mechanisms. The nature of the real world demands more than traditional science can deliver. Yet traditional science has constraints and bounds on its universe of discourse. Complexity science, as presented here, demands that the barriers and constraints be removed in order to gain a more complete view of nature. This tutorial presents a summary of what is entailed by this new methodology.

  20. Links & Snippets Next Article Bookmark and Share

    1. Other Articles Next Article Bookmark and Share


    2. Announcements Next Article Bookmark and Share

      • ComDig Contributing Editors Wanted: Due to the overwhelming success of Complexity Digest in both the academic and practioner communities we are in the fortunate situation to offer one or several positions of contributing editors especially in the areas of economic and business applications. Requirements are a solid background in complexity, reliable access to the Internet, and good editorial skills. Financial support could be available. Please send applications to editor@comdig.org

    3. Conferences Bookmark and Share


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