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friday :: april 28, 2006
how brain cells work: nerve cells talk in pairs

When a group of people tries to decide how to carry out an important task, it is sometimes said that the pivotal discussions do not happen in large, well-attended meetings, but in one-on-one conversations around the water cooler. It turns out that among individual neurons in our brains, the same may hold true.

Likening the process to the sort of casual conversations one might have at a cocktail party, William Bialek and his research team have found that retinal ganglion cells, the nerve cells along the back of our eyes that transmit visual signals to the brain, organize their actions based on communications they have with other individual cells rather than on group-style discussions. The findings, derived from experiments with and mathematical models of groups of 40 cells in the retinas of salamanders, could shed light on how brain cells work as a team.

'We have found that it is possible to understand the group behavior of neural cells based solely on knowledge of these pair interactions,' said Bialek, who wrote the research paper with Princeton colleagues Michael Berry, Ronen Segev and Elad Schneidman. 'From these pair-wise communications, a consensus emerges as to what message will be sent from the eye to the brain. But it comes from many small discussions, not one large one.'

'By eavesdropping on the 'conversations' of individual nerve cells, these researchers learned to predict how small groups of nerve cells in the eye would behave,' said biophysicist C. John Whitmarsh. 'This really is a fantastic result, and could help us understand how brain cells work together to make decisions.'

'It seems that cells at the cocktail party talk primarily, perhaps exclusively, in pairs alone. No one belongs to a group, or takes dictation from a leader, but everyone bases their behavior on what we might call 'informed pair conversations.' They participate in as many of them as they can, listen as much as they can, then act,' Schneidman said.

According to this analogy, the retinal cells would transmit messages based on the information culled from these 'conversations.' However, Bialek said, as at any party, there are subtleties at work as well. 'Just as you might know from past experience that you tend to sympathize with one party guest quite often, but are put off by another, the opinions you draw from different conversations are not all weighted equally,' he said. 'You might nod politely at one person's argument, while agreeing strongly with another, even though they had both come down on the same side of an issue. Nerve cells seem to react to one another in the same way.'

'The evidence pointed us to a more startling discovery, which is that buried in the apparent randomness there are subtle relationships between pairs in the group, and you can actually determine what the group's decision will be, based solely on an awareness of these relationships between pairs,' Berry said. 'Our model does not exclude the possibility that larger groupings within the 40 cells exist. What it shows is that either way, they do not need to be considered to predict the final outcome.' >from *Researchers find nerve cells talk in pairs*. April 20, 2006

related context
groups perform better than the best individuals at solving complex problems. effects of group size: 'groups of three, four, or five perform better on complex problem solving than the best of an equivalent number of individuals.' april 23, 2006
> disorder-induced synchronization. april 14, 2006
> physics of friendship. 'by comparing people to mobile particles randomly bouncing off each other, scientists developed a new model for social networks. the model fits with empirical data to naturally reproduce the community structure, clustering and evolution of general acquaintances and even sexual contacts.' march 10, 2006
> how the brain makes a whole out of parts. 'beginning to reveal how large networks of neurons in the brain extract meaning from the eye image.' january 17, 2006
> why the brain has gray and white matter. 'brain functionality benefits from high synaptic connectivity and short conduction delays.' january 27, 2006
> steps to integrate new neurons into brain's existing operations. december 22, 2005
> swarm intelligence. 'a system whereby the collective behaviours of (unsophisticated) agents interacting locally with their environment cause coherent functional global patterns to emerge.' may 20, 2005
> how animals coordinate their actions. 'group coordination arises naturally from two basic instincts: the need to stay in a group; and the desire by some individuals to act on their own information about where to go.' march 18, 2005
> cooperation evolution. october 8, 2003
> ants community: a perceptual achievement. 'what seems to matter to an ant is the pattern of interactions it experiences rather than a particular message or signal transferred at each interaction.' may 7, 2003
> commons-based peer production in the digitally networked environment. 'groups of individuals successfully collaborate on largescale projects following a diverse cluster of motivational drives and social signals, rather than either market prices or managerial commands.' december 19, 2002

it takes two to speak the truth — one to speak and another to hear
Henry Thoreau

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friday :: april 21, 2006
disease mongering: the corporate sponsored creation of disease

The corporate sponsored creation of disease -- 'disease mongering' -- turns healthy people into patients, wastes precious resources, and causes iatrogenic harm, say the guest editors of a special issue of PLoS Medicine devoted to how drug companies sell sickness.

In the opening essay, the guest editors, Australian journalist Ray Moynihan and clinical pharmacologist David Henry (Newcastle University, Australia), define disease mongering as "the selling of sickness that widens the boundaries of illness and grows the markets for those who sell and deliver treatments."

New diseases are being defined, they say, by panels of specialists who are often funded by industry. Such diseases are then promoted by industry-sponsored 'disease-awareness campaigns,' usually designed to sell drugs rather than inform the public about preventing illness or maintaining health.

Eleven articles in the special issue, published to coincide with an international conference on disease-mongering at Newcastle University on 11-13 April 2006, describe different forms of disease mongering:

* Aspects of ordinary life, such as sexuality, are being medicalized and turned into illnesses. Joel Lexchin (University of Toronto) argues that Pfizer marketed Viagra not just for treating erectile dysfunction due to medical problems like diabetes, but as a drug that 'normal' men could use to enhance their potency.
* Mild problems, such as everyday irritability in children, are portrayed as serious illnesses needing powerful drugs. David Healy (University of Wales) looks at how companies are 'selling' bipolar disorder, leading to a surge of diagnoses of bipolar disorder in American children, some as young as two. "Drugs such as Zyprexa and Risperdal are now being used for preschoolers in America with little questioning of this development," he says.

* Health problems are routinely being framed as extremely common. Steven Woloshin and Lisa Schwartz (Dartmouth Medical School) analyze the news coverage of a little-known condition called 'restless legs syndrome,' a compelling urge to move one's legs. The authors found that the media exaggerated the prevalence of the condition and the need for treatment, and failed to consider the problems of over-diagnosis.

A recent Reuters Business Insight report on so-called lifestyle drugs stated starkly: "the coming years will bear greater witness to the corporate sponsored creation of disease". The special issue, say Moynihan and Henry, is a call for the global health community to challenge this trend. Several articles outline steps that doctors, patients, governments, and the media can take to respond to disease mongering.

"Around the world, there are tentative steps to identify, understand, and combat the threat to human health from the corporate-sponsored selling of sickness," they say. "We trust this theme issue may support and augment these developments." >from *special issue of PLoS Medicine devoted to how drug companies sell sickness* April 10, 2006.

related context
medical ethics and guantanamo bay. march 24, 2006
> why most published research findings are false. august 30, 2005
> 'one world, one health' paradigm: emerging diseases require a global solution. june 24, 2005
> mortality before and after the 2003 invasion of iraq. november 19, 2004
> deadly medicine. november 5, 2004
> science misuse. february 24, 2004
> attacks on science: ethics and public health. january 11, 2002
> public library of science journals. a new model for scientific publishing. september 10, 2001

take you pills, and feel great!

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friday :: april 14, 2006
disorder-induced synchronization

According to a computational study conducted by a group of physicists at Washington University in St. Louis, one may create order by introducing disorder.

While working on their model — a network of interconnected pendulums, or "oscillators" — the researchers noticed that when driven by ordered forces the various pendulums behaved chaotically and swung out of sync like a group of intoxicated synchronized swimmers. This was unexpected — shouldn't synchronized forces yield synchronized pendulums?

But then came the real surprise: When they introduced disorder — forces were applied at random to each oscillator — the system became ordered and synchronized.

"The thing that is counterintuitive is that when you introduce disorder into the system — when the [forces on the pendulums] act at random — the chaos that was present before disappears and there is order," said Sebastian F. Brandt, Washington University physics graduate student in Arts & Sciences and lead author of the study.

The physicists' research is not only hard to grasp for non-physicists, but puzzling for physicists, too. As supervisor Ralf Wessel, Ph.D., Washington University associate professor of physics said, "Every physicist who hears this is surprised."

Research on the role of disorder in complex systems is quite new and not well understood. Wessel hopes that one day its theoretical understanding will be better than it is today. Nevertheless, the researchers believe the model could provide insights outside the realm of theoretical physics.

Neurons, for example, have been modeled as interconnected, or "coupled," oscillators because of the way they interact with one another. In the model, coupled oscillators can be imagined as being tethered to their nearest neighbor, thus influencing their movement. Neurons, on the other hand, may display repetitive electrical activity that can be influenced by the activity of neighboring neurons.

Though it's a bit of a stretch, admits Babette K. Dellen, Ph.D., the study may help to solve previously unexplained observations. Dellen first studied the model system in a neurological context. She set the project aside and then Brandt joined the research group and became intrigued with the concept of disorder-induced synchronization and delved more deeply. Finally, the three put the paper together.

Dellen explains that neurons can exhibit synchronous activity in response to a stimulus. To this point, she said, nobody has come up with an adequate explanation. And Wessel said, "Maybe the details of the neurons are completely irrelevant. Maybe it is only a property of oscillators."

A vital similarity between the model system and neurons is that they are both "nonlinear" — meaning that there is not a linear, or straight-ahead, correlation between the applied force and displacement. In other words, the oscillators in the model may be likened to a child on a swing. Within a small range, the child will move in constant proportion to how hard you push them — if you push twice as hard, they will go twice as far. But nearly all complex systems in nature, like the physicists' model, are nonlinear. Once the child gets to a certain height, pushing twice as hard will not make the child go twice as far.

Neurons are composed of many elements and are typically nonlinear.

"When you hear your favorite music twice as loud you don't double the pleasure," mused Brandt, explaining how one aspect of the brain — hearing — is nonlinear.

While other research has shown that disorder can create order, these studies often involved manipulating parameters within the systems such as changing pendulum length. The researchers say that their work is novel because it involves changing externally applied forces. Thus, they believe, their findings might have potential in the real world, where it would be more difficult to change parameters within the system — neurons, for example — but relatively simple to apply an external forcing.

"This is of course basic research," said Brandt. "But what you can learn from this is that complex systems ... sometimes behave in a very unexpected way, completely opposite to your intuition or expectation. It will be interesting to see if the mechanism that we have found can actually be put to some use." >from *Chaos = Order: WUSTL physicists make baffling discovery*. april 3, 2006

related context
swarm intelligence. may 20, 2005
> how animals coordinate their actions. march 18, 2005
> oscillatory biological networks. may 14, 2004
> synchrony: order is inevitable. april 9, 2003
> network-based movements. march 3, 2003
> smart mobs. october 3, 2002
> understanding the patterns of chaos. february 6, 2002

order-disorder transitions

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friday :: april 7, 2006
aha! creative thinking style

If you've experienced the highs and lows of creative thinking, you know that sometimes the creative well is dry, while at other times creativity is free flowing. It is during the latter times that people often experience so-called "Aha!" moments – those moments of clarity when the solution to a vexing problem falls into place with a sudden insight and you see connections that previously eluded you.

But why do "Aha!" moments sometimes come easily and sometimes not at all? A new study reveals that patterns of brain activity before people even see a problem predict whether they will solve it with or without such an insight, and these brain activity patterns are likely linked to distinct types of mental preparation.

John Kounios of Drexel University, Mark Jung-Beeman of Northwestern University, and their research team report their findings in a new paper to appear in an upcoming issue of the journal Psychological Science.

Previous research by this team demonstrated that the brain functions differently when a person arrives at "Aha!" solutions, compared to methodical solutions. The current study reveals that the distinct patterns of brain activity leading to "Aha!" moments of insight begin much earlier than the time a problem is solved. The research suggests that people can mentally prepare to have an "Aha!" solution even before a problem is presented. Specifically, as people prepare for problems that they solve with insight, their pattern of brain activity suggests that they are focusing attention inwardly, are ready to switch to new trains of thought, and perhaps are actively silencing irrelevant thoughts. These findings are important because they show that people can mentally prepare to solve problems with different thinking styles and that these different forms of preparation can be identified with specific patterns of brain activity. This study may eventually lead to an understanding of how to put people in the optimal "frame of mind" to deal with particular types of problems.

This research team's previous study revealed that just prior to an "Aha!" solution, after a person has been working on solving a problem, the brain momentarily reduces visual inputs, with an effect similar to a person shutting his or her eyes or looking away to facilitate the emergence into consciousness of the solution. The new study extends these findings by suggesting that mental preparation involving inward focus of attention promotes insight even prior to the presentation of a problem. Therefore, it may be that how a person is thinking before problem solving begins is just as important as the kind of thinking involved in reaching the solution, and perhaps even determines whether the solution will be derived with a sudden insight.

Mental preparation that led to insight solutions was generally characterized by increased brain activity in temporal lobe areas associated with conceptual processing, and with frontal lobe areas associated with cognitive control or "top-down" processing. Jung-Beeman noted that "Problem solvers could use cognitive control to switch their train of thought when stuck on a problem, or possibly to suppress irrelevant thoughts, such as those related to the previous problem." In contrast, preparation that led to more methodical solutions involved increased neural activity in the visual cortex at the back of the brain -- suggesting that preparation for deliberate problem solving simply involved external focus of attention on the video monitor on which the problem would be displayed.

More than a century ago, the great scientist Louis Pasteur said "Chance favors only the prepared mind." By this, he meant that sudden flashes of insight don't just happen, but are the product of preparation. According to Kounios, "We have begun to understand how the brain prepares for creative insight. This will hopefully lead to techniques for facilitating it." >from *Aha! Favors the prepared mind*. April 5, 2006

nau21 presentation by nau21 crew + protomembrana by marcel.lν antϊnez roca
friday, april 7, 2006. 20 h
straddle3. c/ riereta, 32 1-3

related context
creative capital. august 19, 2005
> evolution of symbolic thinking. april 6, 2004
> costs of intelligence. october 10, 2003
> biological bases of creativity. october 13, 2003
> creative cities. june 10, 2002
> creative commons. may 24, 2002
> mental operating system. january 4, 2002
> creative technologies. october 29, 2001
> abstract thought on non-human animals. october 16, 2001

our chance to go

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