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 Post subject: More Brain Fun
PostPosted: Wed Mar 21, 2007 7:47 pm 
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From the NYT today. What surprised me was just how specific the effects can be.

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Study Finds Brain Injury Changes Moral Judgment
By BENEDICT CAREY

Damage to an area near the center of the brain, several inches behind the eyes, transforms the way people make moral judgments in life-or-death situations, scientists are reporting. In a new study, people with this rare injury expressed increased willingness to kill or harm another person if doing so would save others’ lives.

The findings are the most direct evidence to date that humans’ native revulsion for hurting others relies on a part of neural anatomy, one that likely evolved before the brain regions responsible for analysis and planning.

The researchers emphasize that the study was small and that the moral decisions were hypothetical; the results cannot predict how people with or without brain injuries will act in real life-or-death situations. Yet the findings, appearing Thursday in the journal Nature, confirm the central role of the damaged region — the ventromedial prefrontal cortex, which is thought to generate social emotions, like compassion.

Previous studies showed that this region was active during moral decision-making, and that damage to it and neighboring areas from severe dementia affected moral judgments. The new study seals the case by demonstrating that a very specific kind of emotion-based judgment is altered when the region is offline. In extreme circumstances, people with the injury will even endorse suffocating an infant if that would save more lives.

“I think it’s very convincing now that there are at least two systems working when we make moral judgments,” said Joshua Greene, a psychologist at Harvard who was not involved in the study. “There’s an emotional system that depends on this specific part of the brain, and another system that performs more utilitarian cost-benefit analyses which in these people is clearly intact.”

The finding could have implications for legal cases. Jurors have reduced sentences based on brain-imaging results, and experts say that any evidence of damage to this ventromedial area could sway judgments of moral competency in some cases.

The new study focused on six patients who had suffered very specific damage to the ventromedial area from an aneurysm or a tumor. The cortex is the thick outer wrapping of the brain, where the distinctly human, mostly conscious functions of thinking and language reside. The term ventral means underneath, and medial means near the middle. The area in adults is about the size of a child’s fist.

People with this injury can be lucid, easygoing, talkative and intelligent, but blind to subtle social cues, making them socially awkward. They also have some of the same moral instincts that others do.

The researchers, from the University of Iowa and other institutions, had them respond to several moral challenges. In one, they had to decide whether to divert a runaway boxcar that was about to kill a group of five workmen. To save they workers they would have to flip a switch, sending the car hurtling into another man, who would be killed.

They strongly favored flipping the switch, just as group of people without injuries did. A third group, with brain damage that did not effect the ventromedial cortex, made the same decision.

All three groups also strongly rejected doing harm to others in situations that were not a matter of trading one certain death for another. They would not send a daughter to work in the pornography industry to fend off crushing poverty, or kill an infant they felt they could not care for.

But a large difference in the participants’ decisions emerged when there was no switch to flip — when they had to choose between taking direct action to kill or harm someone (pushing him in front of the runaway boxcar, for example) and serving a greater good.

Those with ventromedial injuries were about twice as likely as the other participants to say they would push someone in front of the train (if that was the only option), or to poison someone with AIDS who was bent on infecting others, or suffocate a baby whose crying would reveal to enemy soldiers where the subject and family and friends were hiding.

“The difference was very clear, for all of the ventromedial patients,” said Dr. Michael Koenigs, a neuroscientist at the National Institutes of Health who led the study while at the University of Iowa. After repeatedly endorsing killing in these high-conflict situations, he added, one patient told him, “Jeez, I’ve turned into a killer.”

The other authors were Dr. Daniel Tranel of Iowa and neuroscientists from Harvard, the University of Southern California and the California Institute of Technology.

The ventromedial area is a primitive part of the cortex that appears to have evolved to help humans and other mammals navigate social interactions. The area has connections to deeper, unconscious regions like the brain stem, which transmit physical sensations of attraction or discomfort; and the amygdala, a gumdrop of neural tissue that registers threats, social and otherwise. The ventromedial area integrates these signals with others from the cortex, including emotional memories, to help generate familiar social reactions.

“This area when it’s working will give rise to social emotions that we can feel, like embarrassment, guilt, compassion that are critical to guiding our social behavior,” said Dr. Antonio Damasio, a co-author and a neuroscientist at the Brain and Creativity Institute at U.S.C. These sensations in effect put a finger on the brain’s conscious, cost-benefit scale weighing moral dilemmas, Dr. Damasio argues, creating a tension that even trained snipers can feel when having to pull the trigger on an enemy.

This tension between cost-benefit calculations and instinctive emotion in part reflects the brain’s continuing adjustment to the vast social changes that have occurred since the ventromedial area first took shape. The ventromedial area most likely adapted to assist the brain in making snap moral decisions in small kin groups— to spare a valuable group member’s life after a fight, for instance. As human communities became larger and increasingly complex, so did the cortical structures involved in parsing ethical dilemmas. But the more primitive ventromedial area continued to anchor it with emotional insistence an ancient principal: respect for the life of another human being.

“A nice way to think about it,” Dr. Damasio said, “is that we have this emotional system built in, and over the years culture has worked on it to make it even better.”

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PostPosted: Wed Mar 21, 2007 8:39 pm 
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Fascinating. Sounds like it could be the basis for a great science fiction story.

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PostPosted: Wed Mar 21, 2007 9:06 pm 
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Oh, the connection between the brain and emotions has been used a lot in SF. Maybe not compassion specifically. But I can think of at least one Hugo-winning novel that was written partly about an alien race that cannot feel compassion, and I'm sure the idea has been explored elsewhere. The idea, say, of modifying soldiers' brains so they become killing machines incapable of human feeling (and the consequences, usually very bloody) has shown up on TV shows, which is my personal measure for when an idea has become too worn out to use.

The article is really interesting—the idea that it's partly an instinctive and primitive emotion that prevents us from killing one person to save others.

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PostPosted: Wed Mar 21, 2007 11:46 pm 
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Whereas the reasoning-only part of the equation would let us. That tension, which the article describes, strikes me as being (in its more general case) central to much of human personality, although usually we ascribe violence to primitive impulses.

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PostPosted: Wed Mar 21, 2007 11:50 pm 
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We humans are certainly whipsawed by the primitive parts of our brains. Urged to kill when reason would be against it; urged not to when reason would agree it was expedient. . . .

Perhaps human civilization arose in the course of all the arguing and explaining. :P

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“There, peeping among the cloud-wrack above a dark tor high up in the mountains, Sam saw a white star twinkle for a while. The beauty of it smote his heart, as he looked up out of the forsaken land, and hope returned to him. For like a shaft, clear and cold, the thought pierced him that in the end the Shadow was only a small and passing thing: there was light and high beauty for ever beyond its reach.”
― J.R.R. Tolkien, The Return of the King


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PostPosted: Wed Mar 21, 2007 11:56 pm 
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There was another article from the weekend NYT on precursors to moral behavior in primates, but it was too long to quote here. Here's a link for the interested (free registration may be required).

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PostPosted: Thu Mar 22, 2007 12:04 am 
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Also very interesting. I loved this statement of Peter Singer, a moral philosopher at Princeton, quoted from his book “Primates and Philosophers.” He says, “Reason is like an escalator — once we step on it, we cannot get off until we have gone where it takes us.”

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PostPosted: Thu Mar 22, 2007 12:48 am 
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FAS causes this kind of damage.

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PostPosted: Tue Jul 31, 2007 8:05 pm 
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NY Times:

Quote:
Who’s Minding the Mind?
By BENEDICT CAREY

In a recent experiment, psychologists at Yale altered people’s judgments of a stranger by handing them a cup of coffee.

The study participants, college students, had no idea that their social instincts were being deliberately manipulated. On the way to the laboratory, they had bumped into a laboratory assistant, who was holding textbooks, a clipboard, papers and a cup of hot or iced coffee — and asked for a hand with the cup.

That was all it took: The students who held a cup of iced coffee rated a hypothetical person they later read about as being much colder, less social and more selfish than did their fellow students, who had momentarily held a cup of hot java.

Findings like this one, as improbable as they seem, have poured forth in psychological research over the last few years. New studies have found that people tidy up more thoroughly when there’s a faint tang of cleaning liquid in the air; they become more competitive if there’s a briefcase in sight, or more cooperative if they glimpse words like “dependable” and “support” — all without being aware of the change, or what prompted it.

Psychologists say that “priming” people in this way is not some form of hypnotism, or even subliminal seduction; rather, it’s a demonstration of how everyday sights, smells and sounds can selectively activate goals or motives that people already have.

More fundamentally, the new studies reveal a subconscious brain that is far more active, purposeful and independent than previously known. Goals, whether to eat, mate or devour an iced latte, are like neural software programs that can only be run one at a time, and the unconscious is perfectly capable of running the program it chooses.

The give and take between these unconscious choices and our rational, conscious aims can help explain some of the more mystifying realities of behavior, like how we can be generous one moment and petty the next, or act rudely at a dinner party when convinced we are emanating charm.

“When it comes to our behavior from moment to moment, the big question is, ‘What to do next?’ ” said John A. Bargh, a professor of psychology at Yale and a co-author, with Lawrence Williams, of the coffee study, which was presented at a recent psychology conference. “Well, we’re finding that we have these unconscious behavioral guidance systems that are continually furnishing suggestions through the day about what to do next, and the brain is considering and often acting on those, all before conscious awareness.”

Dr. Bargh added: “Sometimes those goals are in line with our conscious intentions and purposes, and sometimes they’re not.”

Priming the Unconscious

The idea of subliminal influence has a mixed reputation among scientists because of a history of advertising hype and apparent fraud. In 1957, an ad man named James Vicary claimed to have increased sales of Coca-Cola and popcorn at a movie theater in Fort Lee, N.J., by secretly flashing the words “Eat popcorn” and “Drink Coke” during the film, too quickly to be consciously noticed. But advertisers and regulators doubted his story from the beginning, and in a 1962 interview, Mr. Vicary acknowledged that he had trumped up the findings to gain attention for his business.

Later studies of products promising subliminal improvement, for things like memory and self-esteem, found no effect.

Some scientists also caution against overstating the implications of the latest research on priming unconscious goals. The new research “doesn’t prove that consciousness never does anything,” wrote Roy Baumeister, a professor of psychology at Florida State University, in an e-mail message. “It’s rather like showing you can hot-wire a car to start the ignition without keys. That’s important and potentially useful information, but it doesn’t prove that keys don’t exist or that keys are useless.”

Yet he and most in the field now agree that the evidence for psychological hot-wiring has become overwhelming. In one 2004 experiment, psychologists led by Aaron Kay, then at Stanford University and now at the University of Waterloo, had students take part in a one-on-one investment game with another, unseen player.

Half the students played while sitting at a large table, at the other end of which was a briefcase and a black leather portfolio. These students were far stingier with their money than the others, who played in an identical room, but with a backpack on the table instead.

The mere presence of the briefcase, noticed but not consciously registered, generated business-related associations and expectations, the authors argue, leading the brain to run the most appropriate goal program: compete. The students had no sense of whether they had acted selfishly or generously.

In another experiment, published in 2005, Dutch psychologists had undergraduates sit in a cubicle and fill out a questionnaire. Hidden in the room was a bucket of water with a splash of citrus-scented cleaning fluid, giving off a faint odor. After completing the questionnaire, the young men and women had a snack, a crumbly biscuit provided by laboratory staff members.

The researchers covertly filmed the snack time and found that these students cleared away crumbs three times more often than a comparison group, who had taken the same questionnaire in a room with no cleaning scent. “That is a very big effect, and they really had no idea they were doing it,” said Henk Aarts, a psychologist at Utrecht University and the senior author of the study.

The Same Brain Circuits

The real-world evidence for these unconscious effects is clear to anyone who has ever run out to the car to avoid the rain and ended up driving too fast, or rushed off to pick up dry cleaning and returned with wine and cigarettes — but no pressed slacks.

The brain appears to use the very same neural circuits to execute an unconscious act as it does a conscious one. In a study that appeared in the journal Science in May, a team of English and French neuroscientists performed brain imaging on 18 men and women who were playing a computer game for money. The players held a handgrip and were told that the tighter they squeezed when an image of money flashed on the screen, the more of the loot they could keep.

As expected, the players squeezed harder when the image of a British pound flashed by than when the image of a penny did — regardless of whether they consciously perceived the pictures, many of which flew by subliminally. But the circuits activated in their brains were similar as well: an area called the ventral pallidum was particularly active whenever the participants responded.

“This area is located in what used to be called the reptilian brain, well below the conscious areas of the brain,” said the study’s senior author, Chris Frith, a professor in neuropsychology at University College London who wrote the book “Making Up The Mind: How the Brain Creates our Mental World.”

The results suggest a “bottom-up” decision-making process, in which the ventral pallidum is part of a circuit that first weighs the reward and decides, then interacts with the higher-level, conscious regions later, if at all, Dr. Frith said.

Scientists have spent years trying to pinpoint the exact neural regions that support conscious awareness, so far in vain. But there’s little doubt it involves the prefrontal cortex, the thin outer layer of brain tissue behind the forehead, and experiments like this one show that it can be one of the last neural areas to know when a decision is made.

This bottom-up order makes sense from an evolutionary perspective. The subcortical areas of the brain evolved first and would have had to help individuals fight, flee and scavenge well before conscious, distinctly human layers were added later in evolutionary history. In this sense, Dr. Bargh argues, unconscious goals can be seen as open-ended, adaptive agents acting on behalf of the broad, genetically encoded aims — automatic survival systems.

In several studies, researchers have also shown that, once covertly activated, an unconscious goal persists with the same determination that is evident in our conscious pursuits. Study participants primed to be cooperative are assiduous in their teamwork, for instance, helping others and sharing resources in games that last 20 minutes or longer. Ditto for those set up to be aggressive.

This may help explain how someone can show up at a party in good spirits and then for some unknown reason — the host’s loafers? the family portrait on the wall? some political comment? — turn a little sour, without realizing the change until later, when a friend remarks on it. “I was rude? Really? When?”

Mark Schaller, a psychologist at the University of British Columbia, in Vancouver, has done research showing that when self-protective instincts are primed — simply by turning down the lights in a room, for instance — white people who are normally tolerant become unconsciously more likely to detect hostility in the faces of black men with neutral expressions.

“Sometimes nonconscious effects can be bigger in sheer magnitude than conscious ones,” Dr. Schaller said, “because we can’t moderate stuff we don’t have conscious access to, and the goal stays active.”

Until it is satisfied, that is, when the program is subsequently suppressed, research suggests. In one 2006 study, for instance, researchers had Northwestern University undergraduates recall an unethical deed from their past, like betraying a friend, or a virtuous one, like returning lost property. Afterward, the students had their choice of a gift, an antiseptic wipe or a pencil; and those who had recalled bad behavior were twice as likely as the others to take the wipe. They had been primed to psychologically “cleanse” their consciences.

Once their hands were wiped, the students became less likely to agree to volunteer their time to help with a graduate school project. Their hands were clean: the unconscious goal had been satisfied and now was being suppressed, the findings suggest.

What You Don’t Know

Using subtle cues for self-improvement is something like trying to tickle yourself, Dr. Bargh said: priming doesn’t work if you’re aware of it. Manipulating others, while possible, is dicey. “We know that as soon as people feel they’re being manipulated, they do the opposite; it backfires,” he said.

And researchers do not yet know how or when, exactly, unconscious drives may suddenly become conscious; or under which circumstances people are able to override hidden urges by force of will. Millions have quit smoking, for instance, and uncounted numbers have resisted darker urges to misbehave that they don’t even fully understand.

Yet the new research on priming makes it clear that we are not alone in our own consciousness. We have company, an invisible partner who has strong reactions about the world that don’t always agree with our own, but whose instincts, these studies clearly show, are at least as likely to be helpful, and attentive to others, as they are to be disruptive.


I like the term "bottom-up decision" for some reason. :D

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PostPosted: Wed Aug 01, 2007 12:48 am 
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In The New Yorker of July 23, an article by Oliver Sacks tells the neurological story of a surgeon from upstate New York who is hit by lightning while making a phone call.

He has an out-of-body experience: "I was flying forwards. Beweildered. I looked around. I saw my own body on the ground. I said to myself, 'Oh shit, I'm dead.' I saw people converging on my body. I saw my kids, had the realization that they'd be O.K. Then I was surrounded by a bluish-white light, and enormous feeling of well-being and peace. I was being drawn up. There was both speed and direction. Then, slam, I was back."


An intensive-care nurse who was next in line to use the phone had performed top-notch CPR on him.


And that's not the wierd part. He regained his mental and physical abilities and continues to be a top surgeon. He has unexpectedly, at the age of 43, developed a transcendent love of music, one that absolutely did not exist before the bolt hit him. He quickly developed an insatiable desire to listen to piano music, especially Chopin. He began to buy sheet music and began to teach himself to play it.

That's not the wierdest part either.


He began to hear music in his head. The first time was in a dream. He was in a tux, onstage, playing something he had written. Unlike in most dreams, the intense involvement in the moment did not go away. He remembered the music precisely and he set about learning how to annotate it properly.


Twelve years after the "accident" he has done so. He is now writing and performing for public consumption.

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PostPosted: Wed Aug 01, 2007 12:58 am 
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Excessively kewl. :)

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PostPosted: Wed Aug 01, 2007 1:22 am 
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I read that article, too. It seems clear to me that there is a whole separate level of "wiring" that is extremely complicated, but unrelated to language or what I think of as thinking, that allows for this kind of "gift" and for savant behaviors. It's fascinating.

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“There, peeping among the cloud-wrack above a dark tor high up in the mountains, Sam saw a white star twinkle for a while. The beauty of it smote his heart, as he looked up out of the forsaken land, and hope returned to him. For like a shaft, clear and cold, the thought pierced him that in the end the Shadow was only a small and passing thing: there was light and high beauty for ever beyond its reach.”
― J.R.R. Tolkien, The Return of the King


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PostPosted: Tue Aug 21, 2007 8:36 pm 
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Now here's a new reason for going to Vegas:

Quote:
August 21, 2007
Sleights of Mind
By GEORGE JOHNSON

The reason he had picked me from the audience, Apollo Robbins insisted, was that I’d seemed so engaged, nodding my head and making eye contact as he and the other magicians explained the tricks of the trade. I believed him when he told me afterward, over dinner at the Venetian, that he hadn’t noticed the name tag identifying me as a science writer. But then everyone believes Apollo — as he expertly removes your wallet and car keys and unbuckles your watch.

It was Sunday night on the Las Vegas Strip, where earlier this summer the Association for the Scientific Study of Consciousness was holding its annual meeting at the Imperial Palace Hotel. The organization’s last gathering had been in the staid environs of Oxford, but Las Vegas — the city of illusions, where the Statue of Liberty stares past Camelot at the Sphinx — turned out to be the perfect locale. After two days of presentations by scientists and philosophers speculating on how the mind construes, and misconstrues, reality, we were hearing from the pros: James (The Amazing) Randi, Johnny Thompson (The Great Tomsoni), Mac King and Teller — magicians who had intuitively mastered some of the lessons being learned in the laboratory about the limits of cognition and attention.

“This wasn’t just a group of world-class performers,” said Susana Martinez-Conde, a scientist at the Barrow Neurological Institute in Phoenix who studies optical illusions and what they say about the brain. “They were hand-picked because of their specific interest in the cognitive principles underlying the magic.”

She and Stephen Macknik, another Barrow researcher, organized the symposium, appropriately called the Magic of Consciousness.

Apollo, with the pull of his eyes and the arc of his hand, swung around my attention like a gooseneck lamp, so that it always pointed in the wrong direction. When he appeared to be reaching for my left pocket he was swiping something from the right. At the end of the act the audience applauded as he handed me my pen, some crumpled receipts and dollar bills, and my digital audio recorder, which had been running all the while. I hadn’t noticed that my watch was gone until he unstrapped it from his own wrist.

“He’s uncanny,” Teller said to me afterward as he rushed off for his nightly show with Penn at the Rio.

A recurring theme in experimental psychology is the narrowness of perception: how very little of the sensory clamor makes its way into awareness. Earlier in the day, before the magic show, a neuroscientist had demonstrated a phenomenon called inattentional blindness with a video made at the Visual Cognition Laboratory at the University of Illinois.

In the video, six men and women — half with white shirts and half with black — are tossing around a couple of basketballs. Viewers are asked to count how many times members of, say, the white team, manage to complete a pass, keeping the ball from the opposition. I dutifully followed the instructions and was surprised when some 15 seconds into the game, laughter began to ripple through the audience. Only when I watched a second time did I see the person in the gorilla suit walking on from stage left. (The video is online at viscog.beckman.uiuc.edu/grafs/demos/15.html.)

Secretive as they are about specifics, the magicians were as eager as the scientists when it came to discussing the cognitive illusions that masquerade as magic: disguising one action as another, implying data that isn’t there, taking advantage of how the brain fills in gaps — making assumptions, as The Amazing Randi put it, and mistaking them for facts.

Sounding more like a professor than a comedian and magician, Teller described how a good conjuror exploits the human compulsion to find patterns, and to impose them when they aren’t really there.

“In real life if you see something done again and again, you study it and you gradually pick up a pattern,” he said as he walked onstage holding a brass bucket in his left hand. “If you do that with a magician, it’s sometimes a big mistake.”

Pulling one coin after another from the air, he dropped them, thunk, thunk, thunk, into the bucket. Just as the audience was beginning to catch on — somehow he was concealing the coins between his fingers — he flashed his empty palm and, thunk, dropped another coin, and then grabbed another from a gentlemen’s white hair. For the climax of the act, Teller deftly removed a spectator’s glasses, tipped them over the bucket and, thunk, thunk, two more coins fell.

As he ran through the trick a second time, annotating each step, we saw how we had been led to mismatch cause and effect, to form one false hypothesis after another. Sometimes the coins were coming from his right hand, and sometimes from his left, hidden beneath the fingers holding the bucket.

He left us with his definition of magic: “The theatrical linking of a cause with an effect that has no basis in physical reality, but that — in our hearts — ought to.”

• • •

In his opening address, Michael Gazzaniga, the president of the consciousness association, had described another form of prestidigitation — a virtual reality experiment in which he had put on a pair of electronic goggles that projected the illusion of a deep hole opening in what he knew to be a solid concrete floor. Jolted by the adrenaline rush, his heart beat faster and his muscles tensed, a reminder that even without goggles the brain cobbles together a world from whatever it can.

“In a sense our reality is virtual,” Dr. Gazzaniga said. “Think about flying in an airplane. You’re up there in an aluminum tube, 30,000 feet up, going 600 miles an hour, and you think everything is all right.”

Dr. Gazzaniga is famous for his work with split-brain patients, whose left and right hemispheres have been disconnected as a last-ditch treatment for severe epilepsy. These are the experiments that have led to the notion, oversimplified in popular culture, that the left brain is predominantly analytical while the right brain is intuitive and laid-back.

The left brain, as Dr. Gazzaniga put it, is the confabulator, constantly concocting stories. But mine was momentarily dumbstruck when, after his talk, I passed through a doorway inside the Venetian Resort Hotel Casino and entered an air-conditioned simulation of the Grand Canal. My eyes were drawn upward to the stunning illusion of a trompe l’oeil sky and what I decided must be ravens flying high overhead. Looking closer, my brain discarded that theory, and I saw that the black curved wings were the edges of discs — giant thumbtacks holding up the sky. Later I was told they were automatic sprinklers, in case the clouds catch fire.

“It’s ‘The Truman Show,’ ” said Robert Van Gulick, a philosopher at Syracuse University, as I joined him at a table overlooking a version of the Piazza San Marco. A sea breeze was wafting through the window, the clouds were glowing in the late afternoon sun (and they were still glowing, around 10:30 p.m., when I headed back toward my hotel). How could we be sure that the world outside the Venetian — outside Las Vegas itself — wasn’t also a simulation? Or that I wasn’t just a brain in a vat in some mad scientist’s laboratory.

Dr. Van Gulick had come to the conference to talk about qualia, the raw, subjective sense we have of colors, sounds, tastes, touches and smells. The crunch of the crostini, the slitheriness of the penne alla vodka — a question preoccupying philosophers is where these personal experiences fit within a purely physical theory of the mind.

Like physicists, philosophers play with such conundrums by engaging in thought experiments. In a recent paper, Michael P. Lynch, a philosopher at the University of Connecticut, entertained the idea of a “phenomenal pickpocket,” an imaginary creature, like Apollo the thief, who distracts your attention while he removes your qualia, turning you into what’s known in the trade as a philosophical zombie. You could catch a ball, hum a tune, stop at a red light — act exactly like a person but without any sense of what it is like to be alive. If zombies are logically possible, some philosophers insist, then conscious beings must be endowed with an ineffable essence that cannot be reduced to biological circuitry.

Dr. Lynch’s fantasy was a ploy to undermine the zombie argument. But if zombies do exist, it is probably in Las Vegas. One evening as I walked across the floor of the Imperial Palace casino — a cacophony of clanging bells and electronic arpeggios — it was easy to imagine that the hominids parked in front of the one-armed bandits were simply extensions of the machines.

“Intermittent conditioning,” suggested Irene Pepperberg, an adjunct associate professor at Brandeis University who studies animal intelligence. If you want to train a laboratory rat to pull a crank to get a food pellet, the reflex will be scratched in deeper if the creature is rewarded with some regularity but not all the time.

Dr. Pepperberg has thrown a wild card into studies of consciousness with her controversial experiments with African gray parrots. With a brain “the size of a walnut,” as she puts it, the birds display what appears to be the cognitive potential of a young child. Her best-known parrot, Alex, can stare at a tray of objects and pick the one that has four corners and is blue. He has also coined his own word for almond — “cork nut.”

With appearances on PBS and a cameo role in a Margaret Atwood novel, “Oryx and Crake,” Alex has entered the popular imagination, while Dr. Pepperberg struggles to find a secure academic position. Critics can’t resist comparing Alex to “Clever Hans,” the famous horse whose arithmetical abilities were exposed as learned responses to his trainer’s subtle cues. Dr. Pepperberg says she controls for that possibility in her experiments and believes her parrots are thinking and expressing themselves with words.

• • •

One evening out on the Strip, I spotted Daniel Dennett, the Tufts University philosopher, hurrying along the sidewalk across from the Mirage, which has its own tropical rain forest and volcano. The marquees were flashing and the air-conditioners roaring — Las Vegas stomping its carbon footprint with jackboots in the Nevada sand. I asked him if he was enjoying the qualia. “You really know how to hurt a guy,” he replied.

For years Dr. Dennett has argued that qualia, in the airy way they have been defined in philosophy, are illusory. In his book “Consciousness Explained,” he posed a thought experiment involving a wine-tasting machine. Pour a sample into the funnel and an array of electronic sensors would analyze the chemical content, refer to a database and finally type out its conclusion: “a flamboyant and velvety Pinot, though lacking in stamina.”

If the hardware and software could be made sophisticated enough, there would be no functional difference, Dr. Dennett suggested, between a human oenophile and the machine. So where inside the circuitry are the ineffable qualia?

Retreating to a bar at the Imperial Palace, we talked about a different mystery he had been pondering: the role words play inside the brain. Learn a bit of wine speak — “ripe black plums with an accent of earthy leather” — and you are suddenly equipped with anchors to pin down your fleeting gustatory impressions. Words, he suggested, are “like sheepdogs herding ideas.”

As he sipped his drink he tried out another metaphor, involving a gold panning technique he had learned about in New Zealand. Lead and gold are similar in density. If you salt the slurry with buck shot and swirl the pan around, the dark pellets will track the elusive flecks of gold.

With a grab bag of devices accumulated over the eons, the brain pulls off the ultimate conjuring act: the subjective sense of I.

“Stage magicians know that a collection of cheap tricks will often suffice to produce ‘magic,’ ” Dr. Dennett has written, “and so does Mother Nature, the ultimate gadgeteer.”

At the end of the magic show where I was fleeced by Apollo, The Amazing Randi called on Dr. Dennett and another volunteer to help with the final act. As Mr. Randi sat on a chair, the two men tightly bound his arms to his thighs with a rope.

“Daniel, would you take off your jacket for me for just a moment?” the conjuror asked. “Now drape it around the front of my hands.”

“A little higher,” Mr. Randi said.

Without missing a beat, he grabbed the collar and pulled it up toward his chin. The audience cheered. Either he had slipped the ropes in a matter of seconds or his hands had been free all along.

“Allow people to make assumptions and they will come away absolutely convinced that assumption was correct and that it represents fact,” Mr. Randi said. “It’s not necessarily so.”


Copyright 2007 The New York Times Company

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PostPosted: Wed Aug 22, 2007 1:27 am 
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Axordil, I wonder if the George Johnson of the most recent article is the same science write who wrote a wonderful book

Machinery of the Mind: Inside the New Science of Artificial Intelligence

The writing style seems familiar.

I've had this book for years, and it has had a profound impact on my knowledge and skill as a programmer and analyst, yet it is completely accessible to the layman.

It is about ideas, not about coding per se, but anyone who understands the ideas should become a better coder if they know when to apply the ideas.

And a lot of it is about the topic of this thread, as some proponents of "Strong AI" look to cognitive models for inspiration, or conversely, look at computational models to explain how the brain (or parts of the brain) work.

BrianIs :) AtYou

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That sounds like an interesting book, brian. Something I could use. R always claims I jump into coding my models before thinking them out well.

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PostPosted: Thu Aug 23, 2007 2:33 pm 
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Coding languages are like any other language: they have logic, a grammar, and rhetoric. If you don't believe the last, you haven't seen as much unpersuasive code as I have. :D

Brian--Wouldn't surprise me.

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The NYT is on a roll this week.

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August 23, 2007
Scientists Induce Out-of-Body Sensation
By SANDRA BLAKESLEE

Using virtual reality goggles, a camera and a stick, scientists have induced out-of-body experiences — the sensation of drifting outside of one’s own body — in healthy people, according to experiments being published in the journal Science.

When people gaze at an illusory image of themselves through the goggles and are prodded in just the right way with the stick, they feel as if they have left their bodies.

The research reveals that “the sense of having a body, of being in a bodily self,” is actually constructed from multiple sensory streams, said Matthew Botvinick, an assistant professor of neuroscience at Princeton University, an expert on body and mind who was not involved in the experiments.

Usually these sensory streams, which include including vision, touch, balance and the sense of where one’s body is positioned in space, work together seamlessly, Prof. Botvinick said. But when the information coming from the sensory sources does not match up, when they are thrown out of synchrony, the sense of being embodied as a whole comes apart.

The brain, which abhors ambiguity, then forces a decision that can, as the new experiments show, involve the sense of being in a different body.

The research provides a physical explanation for phenomena usually ascribed to other-worldly influences, said Peter Brugger, a neurologist at University Hospital in Zurich, Switzerland. After severe and sudden injuries, people often report the sensation of floating over their body, looking down, hearing what is said, and then, just as suddenly, find themselves back inside their body.

The new research is a first step in figuring out exactly how the brain creates this sensation, he said.

The out-of-body experiments were conducted by two research groups using slightly different methods intended to expand the so-called rubber hand illusion.

In that illusion, people hide one hand in their lap and look at a rubber hand set on a table in front of them. As a researcher strokes the real hand and the rubber hand simultaneously with a stick, people have the vivid sense that the rubber hand is their own.

When the rubber hand is whacked with a hammer, people wince and sometimes cry out.

The illusion shows that body parts can be separated from the whole body by manipulating a mismatch between touch and vision. That is, when a person’s brain sees the fake hand being stroked and feels the same sensation, the sense of being touched is misattributed to the fake.

The new experiments were designed to create a whole body illusion with similar manipulations.

In Switzerland, Dr. Olaf Blanke, a neuroscientist at the École Polytechnique Fédérale in Lausanne, Switzerland, asked people to don virtual reality goggles while standing in an empty room. A camera projected an image of each person taken from the back and displayed 6 feet away. The subjects thus saw an illusory image of themselves standing in the distance.

Then Dr. Blanke stroked each person’s back for one minute with a stick while simultaneously projecting the image of the stick onto the illusory image of the person’s body.

When the strokes were synchronous, people reported the sensation of being momentarily within the illusory body. When the strokes were not synchronous, the illusion did not occur.

In another variation, Dr. Blanke projected a “rubber body” — a cheap mannequin bought on eBay and dressed in the same clothes as the subject — into the virtual reality goggles. With synchronous strokes of the stick, people’s sense of self drifted into the mannequin.

A separate set of experiments were carried out by Dr. Henrik Ehrsson, an assistant professor of neuroscience at the Karolinska Insitutute in Helsinki.

Last year, when Dr. Ehrsson was, as he says, “a bored medical student at University College London,” he wondered, he said, “what would happen if you ‘took’ your eyes and moved them to a different part of a room? Would you see yourself where you eyes were placed? Or from where your body was placed?”

To find out, Dr. Ehrsson asked people to sit on a chair and wear goggles connected to two video cameras placed 6 feet behind them. The left camera projected to the left eye. The right camera projected to the right eye. As a result, people saw their own backs from the perspective of a virtual person sitting behind them.

Using two sticks, Dr. Ehrsson stroked each person’s chest for two minutes with one stick while moving a second stick just under the camera lenses — as if it were touching the virtual body.

Again, when the stroking was synchronous people reported the sense of being outside their own bodies — in this case looking at themselves from a distance where their “eyes” were located.

Then Dr. Ehrsson grabbed a hammer. While people were experiencing the illusion, he pretended to smash the virtual body by waving the hammer just below the cameras. Immediately, the subjects registered a threat response as measured by sensors on their skin. They sweated and their pulses raced.

They also reacted emotionally, as if they were watching themselves get hurt, Dr. Ehrsson said.

People who participated in the experiments said that they felt a sense of drifting out of their bodies but not a strong sense of floating or rotating, as is common in full-blown out of body experiences, the researchers said.

The next set of experiments will involve decoupling not just touch and vision but other aspects of sensory embodiment, including the felt sense of the body position in space and balance, they said.

Such mismatches are likely to occur naturally when multi-sensory regions of the brain are deprived of oxygen after injury or shock. Or they may be induced during sleep paralysis, the exertion of extreme sports or intense meditation practices that alter blood flow to specific brain regions.

Copyright 2007 The New York Times Company


I will especially interested in the next iteration.

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I was just using random eye movements in a discussion today, too...

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April 1, 2008
Basics
Blind to Change, Even as It Stares Us in the Face
By NATALIE ANGIER

Leave it to a vision researcher to make you feel like Mr. Magoo.

When Jeremy Wolfe of Harvard Medical School, speaking last week at a symposium devoted to the crossover theme of Art and Neuroscience, wanted to illustrate how the brain sees the world and how often it fumbles the job, he naturally turned to a great work of art. He flashed a slide of Ellsworth Kelly’s “Study for Colors for a Large Wall” on the screen, and the audience couldn’t help but perk to attention. The checkerboard painting of 64 black, white and colored squares was so whimsically subtle, so poised and propulsive. We drank it in greedily, we scanned every part of it, we loved it, we owned it, and, whoops, time for a test.

Dr. Wolfe flashed another slide of the image, this time with one of the squares highlighted. Was the highlighted square the same color as the original, he asked the audience, or had he altered it? Um, different. No, wait, the same, definitely the same. That square could not now be nor ever have been anything but swimming-pool blue ... could it? The slides flashed by. How about this mustard square here, or that denim one there, or this pink, or that black? We in the audience were at sea and flailed for a strategy. By the end of the series only one thing was clear: We had gazed on Ellsworth Kelly’s masterpiece, but we hadn’t really seen it at all.

The phenomenon that Dr. Wolfe’s Pop Art quiz exemplified is known as change blindness: the frequent inability of our visual system to detect alterations to something staring us straight in the face. The changes needn’t be as modest as a switching of paint chips. At the same meeting, held at the Italian Academy for Advanced Studies in America at Columbia University, the audience failed to notice entire stories disappearing from buildings, or the fact that one poor chicken in a field of dancing cartoon hens had suddenly exploded. In an interview, Dr. Wolfe also recalled a series of experiments in which pedestrians giving directions to a Cornell researcher posing as a lost tourist didn’t notice when, midway through the exchange, the sham tourist was replaced by another person altogether.

Beyond its entertainment value, symposium participants made clear, change blindness is a salient piece in the larger puzzle of visual attentiveness. What is the difference between seeing a scene casually and automatically, as in, you’re at the window and you glance outside at the same old streetscape and nothing registers, versus the focused seeing you’d do if you glanced outside and noticed a sign in the window of your favorite restaurant, and oh no, it’s going out of business because, let’s face it, you always have that Typhoid Mary effect on things. In both cases the same sensory information, the same photonic stream from the external world, is falling on the retinal tissue of your eyes, but the information is processed very differently from one eyeful to the next. What is that difference? At what stage in the complex circuitry of sight do attentiveness and awareness arise, and what happens to other objects in the visual field once a particular object has been designated worthy of a further despairing stare?

Visual attentiveness is born of limited resources. “The basic problem is that far more information lands on your eyes than you can possibly analyze and still end up with a reasonable sized brain,” Dr. Wolfe said. Hence, the brain has evolved mechanisms for combating data overload, allowing large rivers of data to pass along optical and cortical corridors almost entirely unassimilated, and peeling off selected data for a close, careful view. In deciding what to focus on, the brain essentially shines a spotlight from place to place, a rapid, sweeping search that takes in maybe 30 or 40 objects per second, the survey accompanied by a multitude of body movements of which we are barely aware: the darting of the eyes, the constant tiny twists of the torso and neck. We scan and sweep and perfunctorily police, until something sticks out and brings our bouncing cones to a halt.

The mechanisms that succeed in seizing our sightline fall into two basic classes: bottom up and top down. Bottom-up attentiveness originates with the stimulus, with something in our visual field that is the optical equivalent of a shout: a wildly waving hand, a bright red object against a green field. Bottom-up stimuli seem to head straight for the brainstem and are almost impossible to ignore, said Nancy Kanwisher, a vision researcher at M.I.T., and thus they are popular in Internet ads.

Top-down attentiveness, by comparison, is a volitional act, the decision by the viewer that an item, even in the absence of flapping parts or strobe lights, is nonetheless a sight to behold. When you are looking for a specific object — say, your black suitcase on a moving baggage carousel occupied largely by black suitcases — you apply a top-down approach, the bouncing searchlights configured to specific parameters, like a smallish, scuffed black suitcase with one broken wheel. Volitional attentiveness is much trickier to study than is a simple response to a stimulus, yet scientists have made progress through improved brain-scanning technology and the ability to measure the firing patterns of specific neurons or the synchronized firing of clusters of brain cells.

Recent studies with both macaques and humans indicate that attentiveness crackles through the brain along vast, multifocal, transcortical loops, leaping to life in regions at the back of the brain, in the primary visual cortex that engages with the world, proceeding forward into frontal lobes where higher cognitive analysis occurs, and then doubling back to the primary visual centers. En route, the initial signal is amplified, italicized and annotated, and so persuasively that the boosted signal seems to emanate from the object itself. The enhancer effect explains why, if you’ve ever looked at a crowd photo and had somebody point out the face of, say, a young Franklin Roosevelt or George Clooney in the throng, the celebrity’s image will leap out at you thereafter as though lighted from behind.

Whether lured into attentiveness by a bottom-up or top-down mechanism, scientists said, the results of change blindness studies and other experiments strongly suggest that the visual system can focus on only one or very few objects at a time, and that anything lying outside a given moment’s cone of interest gets short shrift. The brain, it seems, is a master at filling gaps and making do, of compiling a cohesive portrait of reality based on a flickering view.

“Our spotlight of attention is grabbing objects at such a fast rate that introspectively it feels like you’re recognizing many things at once,” Dr. Wolfe said. “But the reality is that you are only accurately representing the state of one or a few objects at any given moment.” As for the rest of our visual experience, he said, it has been aptly called “a grand illusion.” Sit back, relax and enjoy the movie called You.

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PostPosted: Tue Apr 01, 2008 7:28 pm 
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A long time ago, Primmeh wrote:
Quote:
whipsawed


My moral judgments just dropped another notch because of the use of this "word". :P

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Holbytla wrote:
A long time ago, Primmeh wrote:
Quote:
whipsawed


My moral judgments just dropped another notch because of the use of this "word". :P


I happen to have Webster's Third New International Dictionary (Unabridged) out (Ax's fault).

Quote:
whipsaw n 1 : a narrow pit saw tapering from butt to point, having hooked teeth, and averaging from 5 to 7 1/2 feet in length for use by one or two men.


If you want to sneer at people's vocabularies some more, let's make a thread for that and leave Ax in peace. :D

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