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13 octobre 2012 6 13 /10 /octobre /2012 08:03

We can learn a lot from psychopaths. Certain aspects of their personalities and intellect are often hallmarks of success

Adapted from The Wisdom of Psychopaths, by Kevin Dutton, by arrangement withScientific American/Farrar, Straus and Giroux, LLC (US), Doubleday Canada (Canada), Heinemann (UK), Record (Brazil), DTV (Germany), De Bezige Bij (Netherlands), NHK (Japan), Miraebook (Korea) and Lua de Papel (Portugal). Copyright © 2012 Kevin Dutton

Traits that are common among psychopathic serial killers—a grandiose sense of self-worth, persuasiveness, superficial charm, ruthlessness, lack of remorse and the manipulation of others—are also shared by politicians and world leaders. Individuals, in other words, running not from the police. But for office. Such a profile allows those who present with these traits to do what they like when they like, completely unfazed by the social, moral or legal consequences of their actions.

If you are born under the right star, for example, and have power over the human mind as the moon over the sea, you might order the genocide of 100,000 Kurds and shuffle to the gallows with such arcane recalcitrance as to elicit, from even your harshest detractors, perverse, unspoken deference.

“Do not be afraid, doctor,” said Saddam Hussein on the scaffold, moments before his execution. “This is for men.”

If you are violent and cunning, like the real-life “Hannibal Lecter” Robert Maudsley, you might take a fellow inmate hostage, smash his skull in and sample his brains with a spoon as nonchalantly as if you were downing a soft-boiled egg. (Maudsley, by the way, has been cooped up in solitary confinement for the past 30 years, in a bulletproof cage in the basement of Wakefield Prison in England.)

Or if you are a brilliant neurosurgeon, ruthlessly cool and focused under pressure, you might, like the man I'll call Dr. Geraghty, try your luck on a completely different playing field: at the remote outposts of 21st-century medicine, where risk blows in on 100-mile-per-hour winds and the oxygen of deliberation is thin. “I have no compassion for those whom I operate on,” he told me. “That is a luxury I simply cannot afford. In the theater I am reborn: as a cold, heartless machine, totally at one with scalpel, drill and saw. When you're cutting loose and cheating death high above the snowline of the brain, feelings aren't fit for purpose. Emotion is entropy—and seriously bad for business. I've hunted it down to extinction over the years.”

Geraghty is one of the U.K.'s top neurosurgeons—and although, on one level, his words send a chill down the spine, on another they make perfect sense. Deep in the ghettoes of some of the brain's most dangerous neighborhoods, the psychopath is glimpsed as a lone and merciless predator, a solitary species of transient, deadly allure. No sooner is the word out than images of serial killers, rapists and mad, reclusive bombers come stalking down the sidewalks of our minds.

But what if I were to paint you a different picture? What if I were to tell you that the arsonist who burns your house down might also, in a parallel universe, be the hero most likely to brave the flaming timbers of a crumbling, blazing building to seek out, and drag out, your loved ones? Or that the kid with a knife in the shadows at the back of the movie theater might well, in years to come, be wielding a rather different kind of knife at the back of a rather different kind of theater?

Claims like these are admittedly hard to believe. But they're true. Psychopaths are fearless, confident, charismatic, ruthless and focused. Yet, contrary to popular belief, they are not necessarily violent. Far from its being an open-and-shut case—you're either a psychopath or you're not—there are, instead, inner and outer zones of the disorder: a bit like the fare zones on a subway map. There is a spectrum of psychopathy along which each of us has our place, with only a small minority of A-listers resident in the “inner city.”

Think of psychopathic traits as the dials on a studio mixing deck. If you turn all of them to max, you'll have a soundtrack that's no use to anyone. But if the soundtrack is graded, and some are up higher than others—such as fearlessness, focus, lack of empathy and mental toughness, for example—you may well have a surgeon who's a cut above the rest.

Of course, surgery is just one instance where psychopathic “talent” may prove advantageous. There are others. In 2009, for instance, I decided to perform my own research to determine whether, if psychopaths were really better at decoding vulnerability (as had been found in some studies), there could be applications. There had to be ways in which, rather than being a drain on society, this ability actually conferred some benefit. And there had to be ways to study it.

Enlightenment dawned when I met a friend at the airport. We all get a bit paranoid going through customs, I mused. Even when we're perfectly innocent. But imagine what it would feel like if we did have something to hide—and if an airport security officer were particularly good at picking up on that feeling?

To find out, I decided to conduct an experiment. Thirty undergraduate students took part: half of them high on the Self-Report Psychopathy Scale, and half of them low. There were also five “associates.” The students' job was easy. They had to sit in a classroom and observe the associates' movements as they entered through one door and exited through another, traversing, en route, a small, elevated stage. But there was a catch. They also had to note who was “guilty”: Which one of the five was concealing a scarlet handkerchief?

To raise the stakes and give the observers something to “go on,” the associate with the handkerchief was handed £100. If the jury decided that they were the guilty party—if, when the votes were counted, they came out on top—then they had to hand it back. If, on the other hand, they got away with it, and the finger of suspicion fell heavier on one of the others, they would, in contrast, stand to be rewarded. They would, instead, get to keep the £100.

Which of the students would make the better “customs officers”? Would the psychopaths' predatory instincts prove reliable? Or would their nose for vulnerability let them down?

More than 70 percent of those who scored high on the Self-Report Psychopathy Scale correctly picked out the handkerchief-smuggling associate, compared with just 30 percent of the low scorers. Zeroing in on weakness may well be part of a serial killer's tool kit. But it may also come in handy at the airport.

Trolleyology

Joshua Greene, a psychologist at Harvard University, has observed how psychopaths unscramble moral dilemmas. As I described in my 2011 book, Split-Second Persuasion, he has stumbled on something interesting. Far from being uniform, empathy is schizophrenic. There are two distinct varieties: hot and cold.

Consider, for example, the following conundrum (Case 1), first proposed by the late philosopher Philippa Foot:

A railway trolley is hurtling down a track. In its path are five people who are trapped on the line and cannot escape. Fortunately, you can flip a switch that will divert the trolley down a fork in the track away from the five people—but at a price. There is another person trapped down that fork, and the trolley will kill him or her instead. Should you hit the switch?

Most of us experience little difficulty when deciding what to do in this situation. Although the prospect of flipping the switch isn't exactly a nice one, the utilitarian option—killing just the one person instead of five—represents the “least worst choice.” Right?

Now consider the following variation (Case 2), proposed by philosopher Judith Jarvis Thomson:

As before, a railway trolley is speeding out of control down a track toward five people. But this time you are standing behind a very large stranger on a footbridge above the tracks. The only way to save the five people is to heave the stranger over. He will fall to a certain death. But his considerable girth will block the trolley, saving five lives. Question: Should you push him?

Here you might say we're faced with a “real” dilemma. Although the score in lives is precisely the same as in the first example (five to one), playing the game makes us a little more circumspect and jittery. But why?

Greene believes he has the answer. It has to do with different climatic regions in the brain.

Case 1, he proposes, is what we might call an impersonal moral dilemma and involves those areas of the brain, the prefrontal cortex and posterior parietal cortex (in particular, the anterior paracingulate cortex, the temporal pole and the superior temporal sulcus), principally implicated in our objective experience of cold empathy: in reasoning and rational thought.

Case 2, on the other hand, is what we might call a personal moral dilemma. It hammers on the door of the brain's emotion center, known as the amygdala—the circuit of hot empathy.

Just like most normal members of the population, psychopaths make pretty short work of the dilemma presented in Case 1. Yet—and this is where the plot thickens—quite unlike normal people, they also make pretty short work of Case 2. Psychopaths, without batting an eye, are perfectly happy to chuck the fat guy over the side.

To compound matters further, this difference in behavior is mirrored, rather distinctly, in the brain. The pattern of neural activation in both psychopaths and normal people is well matched on the presentation of impersonal moral dilemmas—but dramatically diverges when things get a bit more personal.

Imagine that I were to pop you into a functional MRI machine and then present you with the two dilemmas. What would I observe as you went about negotiating their moral minefields? Just around the time that the nature of the dilemma crossed the border from impersonal to personal, I would see your amygdala and related brain circuits—your medial orbitofrontal cortex, for example—light up like a pinball machine. I would witness the moment, in other words, that emotion puts its money in the slot.

But in a psychopath, I would see only darkness. The cavernous neural casino would be boarded up and derelict—the crossing from impersonal to personal would pass without any incident.

The Psychopath Mix

The question of what it takes to succeed in a given profession, to deliver the goods and get the job done, is not all that difficult when it comes down to it. Alongside the dedicated skill set necessary to perform one's specific duties—in law, in business, in whatever field of endeavor you care to mention—exists a selection of traits that code for high achievement.

In 2005 Belinda Board and Katarina Fritzon, then at the University of Surrey in England, conducted a survey to find out precisely what it was that made business leaders tick. What, they wanted to know, were the key facets of personality that separated those who turn left when boarding an airplane from those who turn right?

Board and Fritzon took three groups—business managers, psychiatric patients and hospitalized criminals (those who were psychopathic and those suffering from other psychiatric illnesses)—and compared how they fared on a psychological profiling test.

Their analysis revealed that a number of psychopathic attributes were actually more common in business leaders than in so-called disturbed criminals—attributes such as superficial charm, egocentricity, persuasiveness, lack of empathy, independence, and focus. The main difference between the groups was in the more “antisocial” aspects of the syndrome: the criminals' lawbreaking, physical aggression and impulsivity dials (to return to our analogy of earlier) were cranked up higher.

Other studies seem to confirm the “mixing deck” picture: that the border between functional and dysfunctional psychopathy depends not on the presence of psychopathic attributes per se but rather on their levels and the way they are combined. Mehmet Mahmut and his colleagues at Macquarie University in Sydney have recently shown that patterns of brain dysfunction (specifically, patterns in orbitofrontal cortex functioning—the area of the brain that regulates the input of the emotions in decision making) observed in both criminal and noncriminal psychopaths, exhibit dimensional rather than discrete differences. This, Mahmut suggests, means that the two groups should not be viewed as qualitatively distinct populations but rather as occupying different positions on the same continuum.

In a similar (if less high-tech) vein, I asked a class of first-year undergraduates to imagine they were managers in a job placement company. “Ruthless, fearless, charming, amoral and focused,” I told them. “Suppose you had a client with that kind of profile. To which line of work do you think they might be suited?”

Their answers couldn't have been more insightful. CEO, spy, surgeon, politician, the military … they all popped up in the mix. Amongst serial killer, assassin and bank robber.

“Intellectual ability on its own is just an elegant way of finishing second,” one successful CEO told me. “Remember, they don't call it a greasy pole for nothing. The road to the top is hard. But it's easier to climb if you lever yourself up on others. Easier still if they think something's in it for them.”

Jon Moulton, one of London's most successful venture capitalists, agrees. In a recent interview with the Financial Times, he lists determination, curiosity and insensitivity as his three most valuable character traits.

No prizes for guessing the first two. But insensitivity? The great thing about insensitivity, Moulton explains, is that “it lets you sleep when others can't.”

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13 octobre 2012 6 13 /10 /octobre /2012 07:35

 

Investigations of genetic variants and how the body and brain change during recovery might offer insights into why some people never recover from trauma

She pleaded with him to let her go, and he said that he would. So when he stopped on a bridge at around 2 a.m. and told her to get out, she thought she was free. Then he motioned for her to jump. “That's the time where my system, I think, just lost it,” Ebaugh recalls. Succumbing to the terror and exhaustion of the night, she fainted.

Ebaugh awoke in freefall. The man had thrown her, limp and handcuffed, off the bridge four storeys above a river reservoir. When she hit the frigid water, she turned onto her back and started kicking. “At that point, there was no part of me that thought I wasn't going to make it,” she says.

Few people will experience psychological and physical abuse as terrible as the abuse Ebaugh endured that night. But extreme stress is not unusual. In the United States, an estimated 50–60% of people will experience a traumatic event at some point in their lives, whether through military combat, assault, a serious car accident or a natural disaster. Acute stress triggers an intense physiological response and cements an association in the brain's circuits between the event and fear. If this association lingers for more than a month, as it does for about 8% of trauma victims, it is considered to be post-traumatic stress disorder (PTSD). The three main criteria for diagnosis are recurring and frightening memories, avoidance of any potential triggers for such memories and a heightened state of arousal.

Ebaugh experienced these symptoms in the months after her attack and was diagnosed with PTSD. But with the help of friends, psychologists and spiritual practices, she recovered. After about five years, she no longer met the criteria for the disorder. She opened her own private practice, married and had a son.

About two-thirds of people diagnosed with PTSD eventually recover. “The vast majority of people actually do OK in the face of horrendous stresses and traumas,” says Robert Ursano, director of the Center for the Study of Traumatic Stress at the Uniformed Services University of the Health Sciences in Bethesda, Maryland. Ursano and other researchers want to know what underlies people's mental strength. “How does one understand the resilience of the human spirit?” he asks.

Since the 1970s, scientists have learned that several psychosocial factors — such as strong social networks, recalling and confronting fears and an optimistic outlook — help people to recover. But today, scientists in the field are searching for the biological factors involved. Some have found specific genetic variants in humans and in animals that influence an individual's odds of developing PTSD. Other groups are investigating how the body and brain change during the recovery process and why psychological interventions do not always work. The hope is that this research might lead to therapies that enhance resilience.

A natural response
Although no one can fully understand what was going on in Ebaugh's mind during her attack, scientists have some idea of what was happening to her body. As soon as Ebaugh saw her attacker and his knife, her brain's pituitary gland sent signals to her adrenal glands, atop the kidneys, to start pumping out the stress hormones adrenaline and cortisol. In turn, her pulse quickened, her blood pressure rose and beads of sweat formed on her skin. Her senses sharpened and her neural circuits formed strong memories, so that if she ever encountered this threat in the future, she would remember the fear and flee.

The repercussions were profound. For the first week after the abduction, “I felt like a newborn baby”, Ebaugh says, “like I had to be held, or at least be in the presence of somebody”. She shivered constantly, was easily startled and felt only fear. She could not go near the grocery store.

Nearly every trauma victim experiences PTSD symptoms to some degree. Many people who are diagnosed with the disorder go on to have severe depression, substance-abuse problems or suicidal thoughts. PTSD can take a horrific toll. Between 2005 and 2009, as a growing number of soldiers faced multiple deployments in Iraq and Afghanistan, suicide rates in the US Army and Marines nearly doubled.

Over the past two decades, researchers have used various kinds of imaging techniques to peer inside the brains of trauma victims. These studies report that in people with PTSD, two areas of the brain that are sensitive to stress shrink: the hippocampus, a deep region in the limbic system important for memory, and the anterior cingulate cortex (ACC), a part of the prefrontal cortex that is involved in reasoning and decision-making. Functional magnetic resonance imaging (fMRI), which tracks blood flow in the brain, has revealed that when people who have PTSD are reminded of the trauma, they tend to have an underactive prefrontal cortex and an overactive amygdala, another limbic brain region, which processes fear and emotion (see 'The signature of stress').

People who experience trauma but do not develop PTSD, on the other hand, show more activity in the prefrontal cortex. In August, Kerry Ressler, a neuroscientist at Emory University in Atlanta, Georgia, and his colleagues showed that these resilient individuals have stronger physical connections between the ACC and the hippocampus. This suggests that resilience depends partly on communication between the reasoning circuitry in the cortex and the emotional circuitry of the limbic system. “It's as if [resilient people] can have a very healthy response to negative stimuli,” says Dennis Charney, a psychiatrist at the Mount Sinai School of Medicine in New York, who has conducted several brain-imaging studies of rape victims, soldiers and other trauma survivors.

Environmental protection
After her abduction, Ebaugh began seeing a psychotherapist and several alternative-medicine practitioners. But more than anything else, she attributes her resilience to being surrounded by caring people — beginning within minutes of her escape.

After Ebaugh crawled up the rocky riverbank, a truck driver picked her up, took her to a nearby convenience store and bought her a cup of hot tea. Police, when they arrived, were sympathetic and patient. The doctor at the hospital, she says, treated her like a daughter. A close friend took her in for a time. And her family offered reassurance and emotional support. “For the first month, I almost had to tell people to stop coming because I was so surrounded by friends and community,” she says.

Studies of many kinds of trauma have shown that social support is a strong buffer against PTSD and other psychological problems. James Coan, a psychologist at the University of Virginia in Charlottesville, has done a series of experiments in which women lie in an fMRI scanner and see 'threat cues' on a screen. They are told that between 4 and 10 seconds later, they may receive a small electric shock on the ankle. The cue triggers sensory arousal and activates brain regions associated with fear and anxiety, but when the women hold the hands of their husbands or friends, these responses diminish.

Social interactions are complex and involve many brain circuits and chemicals; no one knows exactly why they provide relief. Being touched by someone is thought to stimulate the release of natural opioids, such as endorphins, in the brain. The ACC is packed with opioid receptors, suggesting that touch could influence its response to stress.

Other clues come from the hormone oxytocin, which courses through the brain during social interaction and has been shown to boost trust and reduce anxiety. In one imaging study, participants viewed frightening images after receiving nasal sprays of either oxytocin or a placebo. Those who sniffed oxytocin showed reduced activation in the amygdala and weaker connections between the amygdala and the brainstem, which control some stress responses, such as heart rate. The oxytocin surge that comes from being around other people could, like endorphins, help to reduce the stress response.

Past social interactions may also affect how a person responds to trauma. Chronic neglect and abuse unquestionably lead to a host of psychological problems and a greater risk of PTSD. Ressler, however, points to a factor that is well recognized but poorly understood: 'stress inoculation'. Researchers have found that rodents and monkeys, at least, are more resilient later in life if they experience isolated stress events, such as a shock or a brief separation from their mothers, early in infancy.

Ebaugh says that early stress — and the confidence she gained in conquering it — helped her to recover from her traumatic abduction. She was born with a condition that made her feet turn inwards. At age ten, she underwent surgery to rebuild her knees followed by a year of intensive rehabilitation. “It wasn't foreign to me to be hurt and have to walk the walk of being strong again,” she says. “It's like a muscle, I think, that gets built up.”

Resilient by nature
Although most people, like Ebaugh, recover from trauma, some never do. Some scientists are seeking explanations for such differences in the epigenome, the chemical modifications that help to switch genes on and off (see page 171). Others are looking in the genes themselves. Take, for example, FKBP5, a gene involved in hormonal feedback loops in the brain that drive the stress response. In 2008, Ressler and his colleagues showed that in low-income, inner-city residents who had been physically or sexually abused as children, certain variants in FKBP5 predisposed them to developing PTSD symptoms in adulthood. Other variants offered protection.

The most talked-about biological marker of resilience is neuropeptide Y (NPY), a hormone released in the brain during stress. Unlike the stress hormones that put the body on high alert in response to trauma, NPY acts at receptors in several parts of the brain — including the amygdala, prefrontal cortex, hippocampus and brainstem — to help shut off the alarm. “In resiliency, these brake systems are turning out to be the most relevant,” says Renu Sah, a neuroscientist at the University of Cincinnati in Ohio.

Interest in NPY and resilience took off in 2000, partly because of a study of healthy US Army soldiers who participated in a survival course designed to simulate the conditions endured by prisoners of war, such as food and sleep deprivation, isolation and intense interrogations. NPY levels went up in the soldiers' blood within hours of the interrogations. Special Forces soldiers who had trained to be resilient had significantly higher NPY levels than typical soldiers.

Researchers are now conducting animal experiments to study how NPY works. In one experiment, a team at the Indiana University School of Medicine in Indianapolis restrained a rat in a tight-fitting plastic pouch for 30 minutes, then released it into a box with another rat. The restraint made the rat so anxious that it avoided interacting with the other animal for 90 minutes. But when rats were injected with NPY before the treatment, they interacted with cage-mates as if nothing had happened.

The work could lead to treatments. Charney's group at Mount Sinai is carrying out a phase II clinical trial of an NPY nasal spray for individuals with PTSD. Others are investigating small molecules that can cross the blood–brain barrier and block certain receptors that control NPY release.

Conflict resolution
The US military is leading the hunt for additional biological markers of resilience. Since 2008 — driven in part by soaring suicide rates among soldiers — the US Army has collaborated with the National Institute of Mental Health and several academic institutions on a US$65-million project called Army STARRS (the Study to Assess Risk and Resilience in Servicemembers). The project has many parts, including a retrospective look at de-identified medical and administrative records for 1.6 million soldiers, in search of early warnings of suicide, PTSD and other mental-health problems. STARRS scientists are also collecting data — such as blood samples, medical histories and cognitive testing results — on tens of thousands of current soldiers. The researchers expect to publish their first findings early next year.

The military also funds research into animal models of resilience. Most rodents will quickly learn to associate painful foot shocks with a certain cue, such as a tone or a specific cage. After they have learned the association, the rodents freeze on experiencing the cue, even without the shock. Several years ago, Abraham Palmer, a geneticist now at the University of Chicago in Illinois, made a line of resilient mice by selectively breeding mice that froze for abnormally short periods of time. After about four generations, he had mice that froze for about half the time of typical animals. The effect was not due to a difference in pain sensitivity or general learning ability. This month, Luke Johnson, a neuroscientist at the Uniformed Services University, will present data at the Society for Neuroscience meeting in New Orleans, Louisiana, showing that these mice have uncommonly low activity in the amygdala and hippocampus, consistent with human studies of PTSD resilience. They also have low levels of corticosterone, a stress hormone, in their urine.

“They have a quieter system, even at rest,” says Johnson. “It suggests that there are underlying biological traits that are associated with the capacity of the animal for fear memory.” In future experiments, Johnson plans to use the mice to study NPY and potential new therapies.

Ebaugh, who now specializes in therapy for trauma victims, agrees that drug-based treatments could aid in recovery. But some people may find relief elsewhere. Religious practices — especially those that emphasize altruism, community and having a purpose in life — have been found to help trauma victims to overcome PTSD. Ebaugh says that yoga, meditation, natural remedies and acupuncture worked for her.

Today, she buys groceries at the plaza where she was abducted, and she drives over the bridge she was thrown from as though it were any other road. She says that she has forgiven the man who abducted her. When she reflects on what he did, it's not with anger, sadness or fear. “It doesn't feel like it affects my life at all at this point, at least not in a negative way,” she says. “In a positive way, it's been a huge teacher.”

 

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13 octobre 2012 6 13 /10 /octobre /2012 07:31

This month's issue of Scientific American features an excerpt from Kevin Dutton's new book, The Wisdom of Psychopaths (Scientific American / Farrar, Straus and Giroux, October 2012). In the excerpt, Dutton, a research psychologist at the Calleva Research Center for Evolution and Human Science at the University of Oxford, explains how many of the personality traits and thinking styles that characterize psychopaths are also hallmarks of successful surgeons, politicians and military leaders. Sometimes, it's helpful to think like a psychopath. You can assess your own psychopathic traits by participating in The Psychopath Challenge.

To get a sense of what it's like to interact with a psychopath—and how the psychopathic mind works—read the transcript of an interview with a psychopath below. The transcript also appears in Dutton's previous book, Split-Second Persuasion (Houghton Mifflin Harcourt, 2011).

 

Secure Unit, Summer 1995

"What are you doing tonight?"

"Don't know. Going out probably. Pub. Club, maybe? Why?"

"What are you going to do there?"

"What do you mean, what am I going to do there? Usual stuff, I suppose. Meet up with some mates. Have a few beers..."

"Pull some birds?"

"Yeah, I guess. If I'm lucky."

"And what if you're not?"

"Not what?"

"Lucky."

"There's always next time."

He nods. Looks down. Looks up again. It's hot. This is a place where the windows don't open. Not because they won't. But because they can't. Don't try to outsmart him, the psychiatrist had said. You've got no chance. Your best bet is just to play it straight.

"Do you think of yourself as a lucky person, Kev?"

I'm confused. "What do you mean?"

He smiles. "Thought so."

I swallow. "What?"

Silence. For about 10 seconds.

"There's always one, isn't there, Kev? The one you think about as you're eating your hot dog on the way home. The one that got away. The one you 'never got round to' because you were just too fucking scared. Scared that if you did get round to her, you'd end up doing exactly what you end up doing every other Friday night. Eating shit. Talking shit. Feeling shit."

I think about it. He's right. The bastard. Sort-of. A sea of faces strobes across my brain as I stand in the middle of an empty dance floor somewhere. Anywhere. What am I doing there? Who am I with? The promise of emptiness yanks me back to the present. How long have I been gone? Five, 10 seconds? I need to respond. And fast.

"So what would you do?" I say. Pathetic.

"The business." No hesitation.

"The business?" I repeat. I'm on the ropes here. "And what if she's not interested?"

"There's always later."

"Later? What do you mean?"

"I think you know what I mean."

Silence. Another 10 seconds. I do know what he means and it's time to wrap things up. I rummage around in my briefcase and power down the laptop. A nurse looks in through the glass.

"Mike," I say, "it's time for me to check out. It's been good talking to you. I hope things go okay for you in here."

Mike gets up. Shakes my hand. Coils his arm gently around my shoulders.

"Look Kev, I can see that I've offended you and I really didn't mean to do that. I'm sorry. Enjoy yourself tonight. And when you see her—her, you'll know who she is—think of me."

He winks. I feel a pulse of affection and am filled with self-loathing. I say: "I'm not offended, Mike. Really. I mean it. I've learned a lot. It's brought it home to me just how different we are. You and me. How differently we're wired. It's helped. It really has. And I guess the bottom line is this: That's why you're in here and I'm (I point at the window) out there." I shrug, as if to say it's not my fault. As if, in a parallel universe, things could just as easily have turned out different.

Silence.

Suddenly, I'm aware that there's a chill in the room. It's physical. Palpable. I can feel it on my skin. Under my skin. All over me. This is something I've read about in books. But have, up until this moment, never experienced. I stand for five agonizing seconds in a stare 40 below. Ever so slowly, as if some new kind of gravity has been seeping in unnoticed through the vents, I feel the arm vacate my shoulders.

"Don't let your brain piss you about, Kev. All those exams—sometimes they get in the way. There's only one difference between you and me. Honesty. Bottle. I want it, I go for it. You want it, you don't.

"You're scared, Kev. Scared. You're scared of everything. I can see it in your eyes. Scared of the consequences. Scared of getting caught. Scared of what they'll think. You're scared of what they'll do to you when they come knocking at your door. You're scared of me.

"I mean, look at you. You're right. You're out there, I'm in here. But who's free, Kev? I mean really free? You or me? Think about that tonight. Where are the real bars, Kev? Out there?" (He points at the window.) "Or in here?" (He reaches forward and, ever so lightly, touches my left temple)

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4 octobre 2012 4 04 /10 /octobre /2012 12:43

The Earth is flat. A full moon leads to more crime. Humans were created less than 10,000 years ago.

If you made your way through even the most general of science educations, the above statements should strike you as suspect. Having a Copernican worldview challenged by such a statement, for example, may encourage you to take a quick look around various sources of information to stabilize your psyche. When contradicting information shakes our foundations, how do we respond?

A few weeks ago I wrote a critique of an evaluation of a video by science educator Bill Nye that sparked a debate about how to best communicate a scientific position to a resistant public. If nearly half of Americans hold a creationist worldview, is Bill Nye’s video against teaching creationism to children an effective way to voice the scientific position to a wide audience? (Nye’s video was at 4.5 million views at the time of this writing.) I feel an informed approach is lacking in discussions like these. Communication research is replete with the science of persuasion. Here I want to deal with perhaps the most interesting case: persuading an ideologically entrenched audience that a worldview is incorrect.

Information Processing and Defensive Motivations

A goal of good science communication is to inform attitudes. How the public judges the safety of vaccinations, the nutritional value of genetically modified foods, or the veracity of evolution depends on sound explication. Especially today, when people can instantly get any information they want, it is essential for science communicators to understand how the information people are finding is changing their attitudes.

Research in the information processing paradigm seeks to answer how information modulated by our cognition affects attitudes. Whether we are trying to come to an informed decision, developing our values, or just trying to learn, information processing theories define the routes we take. The most successful theories in this field put human information processing into two modes. We process information either heuristically or systematically (also called System 1 and System 2 or peripheral and central processing). In heuristic processing we rely on cues and gut instincts to help us. For example, if we read an article by a NASA scientist, and do not have the capacity to evaluate the content ourselves, the authority of the author could be enough to superficially judge the information as accurate. Conversely, if we did have the capacity to evaluate the arguments in the NASA article, we could systematically process the information: looking deeply into the arguments and internalizing new ideas while updating old ones.

People are misers of mental effort. If we don’t have the interest or the capacity to look into the arguments, if the message isn’t personally relevant, if we judge that we already know all we need to know about a topic, there is no reason to spend precious mental resources. Thus, heuristic processing is our default mode (think of superficially surfing the web). Looking critically at information takes motivation. This is where information processing research informs effective science communication.

Researches have found that people who systematically process information form longer lasting attitudes that are more resistant to counter-arguments [1]. For example, if an article provides enough information and instills sufficient interest so the reader can systematically process it, the reader’s ensuing judgments will be based on the actual content of the article [2]. Judgments based on a heuristic scanning of the article will instead be based on peripheral cues such as message length, message source, or emotion, rather than on judgment-relevant information [2]. Because we don’t want to waste mental effort, systematic processing is subject to many more constraints such as time, degree of personal relevance, and general clarity of the message. So systematic processing is crucial for contentious topics like creationism and evolution.

Seeking and processing accurate information is one thing, but encountering worldview-contradicting information is another. Even though the science on the issue of evolution versus creationism is one-sided, it doesn’t seem to matter. Refuting creationism is fundamentally different from merely disseminating scientifically accurate information. The reason that creationism cannot be dispatched in the same way belief in a flat Earth can, for example, is that creationism entails an entire worldview with its own set of values distinct from concerns of scientific accuracy. Therefore, even systematically processing accurate information about evolution may do little to change creationist attitudes. The motivation is what matters here.

The desire to form attitudes that square with the available facts is straightforward from an information processing perspective. When determining whether genetically modified foods are as nutritious as conventional foods, for example, we expend as much mental effort as is needed to come to a confident conclusion [1]. We process until we feel we have formed an accurate attitude about genetically modified foods. However, with a topic like creationism, the standard of what is considered sufficient information changes dramatically. As opposed to a motivation to be accurate, encountering a critique of a worldview instills a defensive motivation.

Researchers have found that “the sufficiency of a defensive processing strategy is determined, not by its ability to increase confidence in the objective accuracy of the conclusion, but by its ability to increase confidence in a preferred conclusion [my emphasis] that is consistent with material interests or self-defining beliefs [3].” When a creationist worldview is shaken, the desire to be in accordance with the scientific evidence can fly out the window, biology be damned. Information processing becomes biased in favor of supporting and therefore maintaining belief. And science is the ultimate worldview shaker. Biased systematic processing may also explain why creationism is so hard to root out: effortful processing favoring a particular worldview makes the view more resistant to counter-arguments.

Intelligently Designing Our Messages

In my critique of the Bill Nye article by Marc Kuchner, I stated that the suggestions offered by the “business communications expert” were hollow and insincere. I also claimed that because Nye’s video was a candid expression and not meant to be a primer on evolution, the critical style could be effective for some people. Looking at the persuasion literature, perhaps my critique was not as nuanced as it needed to be. For some, Nye’s message was surely tantamount to blasphemy (indeed, creationists responded quickly), and the resulting motivation to defend a worldview could bias evaluations of evolution.

On the other hand, Nye’s characterization of creationism could be seen as an implication that those of the “creation persuasion” hold views that do not reflect reality. A call to reflect accuracy in our attitudes may encourage a thorough look at the evidence for each position, which is all one can hope for. But disentangling these motivations can be tricky. Just what kind of communication transforms a desire to be accurate into a desire to support prior beliefs? It depends on how much one knows about the topic, how much one needs to know, and a capacity to evaluate the arguments, among other things.

How should we communicate science that potentially contradicts a worldview? Communication research suggests an effort to switch motivations. Anecdotally, the most fruitful conversation I’ve had in this debate was with a creationist who simply wanted a clearer explanation of evolution than was offered in his religious education. The desire to have accurate attitudes allowed him to dispassionately consider the evidence. It was my job as a communicator to give him the ability to understand the basics of the theory, to be able to systematically process what I was saying. What resulted was an enduring embrace of the science. By crafting a message that fostered a desire to be accurate, rather than one of defense, I had changed a mind. My case study of one should hardly inform science communication as a whole, but it shouldn’t be dismissed either.

The research on risk communication offers a similar conclusion. Self-affirmation theory [4] proposes that our thoughts and behaviors are motivated by the desire to maintain self-worth or self-integrity. When threatening information is encountered, people tend to respond defensively in order to maintain this positive self-image. For example, a coffee drinker who thinks he is a “healthy” person may discredit information that claims drinking coffee has health risks. However, if a message can affirm a person’s image through other means, like bolstering important values, the need to respond defensively to threatening information is reduced [5]. This may be the lynchpin in communicating possibly worldview-shaking messages:

Salient, self-affirming thoughts should make it easier to be objective about other, self-threatening information; they should reduce the pressure to diminish the threat inherent in this information. In this way, self-affirming thoughts may be an effective means of reducing thought distorting defense mechanisms such as denial and rationalization (Steele, 1988, p. 290).

Resolving the evolution versus creationism debate may then be about appealing to shared values, like a desire to have beliefs supported by good reasons or evidence. Communicators can affirm an audience’s self-integrity by pointing this out. This approach dovetails nicely with shifting from a defensive to an accuracy motivation. Indeed, this sort of appeal has been found to reduce the defensive processing of messages and increase their acceptance [6]. But it gets more complicated. In one study, having participants reflect on small acts of kindness they recently completed had a similar self-affirming effect. By bolstering self-image (i.e., “I’m a good/smart person”), one is more receptive to threatening information, and processes it in a less biased way [6]. This surely has implications for the language used in potentially threatening messages. Lowering someone’s self image by calling him or her in effect “not good” or “stupid” could easily trigger a defensive cognitive stance. It needs to be made clear when arguing for evolution that its acceptance does not reduce a person’s integrity or self-worth, though many fundamentalist mindsets will claim otherwise.

It could very well be that the emphasis on “science versus religion” has poisoned the well by emphasizing belief defense over accuracy. If the frame can somehow be shifted, and science communicators are diligent in providing the public with the best information available, all we can ask for is that the public thinks deeply about it, and inform attitudes with it.

References:

1. Eagly, A., & Chaiken, S. (1993). The psychology of attitudes. San Diego, CA: Harcourt Brace Jovanovich.

2. Chen, S., & Chaiken, S. (1999). The heuristic-systematic model in its broader context. In S. Chaiken & Y. Trope (Eds.), Dual- process theories in social psychology (pp. 73–96). New York: Guilford.

3. Giner-Sorolla, R., & Chaiken, S. (1997). Selective use of heuristic and systematic processing under defense motivation. Per Soc Psychology Bull, 23, 84–97.

4. Steele, C. (1988). The psychology of self-affirmation: Sustaining the integrity of the self. In L. Berkowitz (Ed.), Advances in experimental social psychology (Vol. 21, pp. 261–302). New York: Academic Press.

5. Sherman, D., Nelson, L., & Steele, C. (2000). Do messages about health risks threaten the self? Increasing the acceptance of threatening health messages via self-affirmation. Per Soc Psychology Bull, 26(9), 1046–1058.

6. Reed, M., & Aspinwall, L. (1998). Self-affirmation reduces biased processing of health-risk information. Mot & Emot, 22(2), 99–132.

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4 octobre 2012 4 04 /10 /octobre /2012 12:33

In the 1970s biologist Sydney Brenner and his colleagues began preserving tiny hermaphroditic roundworms known as Caenorhabditis elegans in agar and osmium fixative, slicing up their bodies like pepperoni and photographing their cells through a powerful electron microscope. The goal was to create a wiring diagram—a map of all 302 neurons in the C. elegans nervous system as well as all the 7,000 connections, or synapses, between those neurons. In 1986 the scientists published a near complete draft of the diagram. More than 20 years later, Dmitri Chklovskii of Janelia Farm Research Campus and his collaborators published an even more comprehensive version. Today, scientists call such diagrams "connectomes."

So far, C. elegans is the only organism that boasts a complete connectome. Researchers are also working on connectomes for the fruit fly nervous system andthe mouse brain. In recent years some neuroscientists have proposed creating a connectome for the entire human brain—or at least big chunks of it. Perhaps the most famous proponent of connectomics is Sebastian Seung of the Massachusetts Institute of Technology, whose impressive credentials, TED talkpopular book, charisma and distinctive fashion sense (he is known to wear gold sneakers) have made him a veritable neuroscience rock star.
 
Other neuroscientists think that connectomics at such a large scale—the human brain contains around 86 billion neurons and 100 trillion synapses—is not the best use of limited resources. It would take far too long to produce such a massive map, they argue, and, even if we had one, we would not really know how to interpret it. To bolster their argument, some critics point out that the C. elegans connectome has not provided many insights into the worm's behavior. In a debate* with Seung at Columbia University earlier this year, Anthony Movshon of New York University said, "I think it's fair to say…that our understanding of the worm has not been materially enhanced by having that connectome available to us. We don't have a comprehensive model of how the worm's nervous system actually produces the behaviors. What we have is a sort of a bed on which we can build experiments—and many people have built many elegant experiments on that bed. But that connectome by itself has not explained anything."

Because a lone connectome is a snapshot of pathways through which information might flow in an incredibly dynamic organ, it cannot reveal how neurons behave in real time, nor does it account for the many mysterious ways that neurons regulate one another's behavior. Without such maps, however, scientists cannot thoroughly understand how the brain processes information at the level of the circuit. In combination with other tools, the C. elegans connectome has in fact taught scientists a lot about the worm's behavior; partial connectomes that researchers have established in the crustacean nervous system have been similarly helpful. Scientists are also learning how to make connectomes faster than before and to enhance the information they provide. Many researchers in the field summarize their philosophy like this: "A connectome is necessary, but not sufficient."

"Some people say we don't know anything about how C. elegans's brain works and I am like, 'Yes, we do!'" says Cornelia Bargmann of The Rockefeller University, who has studied the nematode for more than two decades and attended the Columbia debate. "A lot of what we know about C elegans's rapid behaviors we have learned through and with the connectome. Every time we do an experiment, we look at those wiring diagrams and use them as a starting point for generating hypotheses."

 

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4 octobre 2012 4 04 /10 /octobre /2012 12:21

A common complaint about wrinkle-masking Botox is that recipients have difficulty displaying emotions on their faces. That side effect might be a good thing, however, for people with treatment-resistant depression.

In the first randomized, controlled study on the effect of botulinum toxin—known commercially as Botox—on depression, researchers investigated whether it might aid patients with major depressive disorder who had not responded to antidepressant medications. Participants in the treatment group were given a single dose (consisting of five injections) of botulinum toxin in the area of the face between and just above the eyebrows, whereas the control group was given placebo injections. Depressive symptoms in the treatment group decreased 47 percent after six weeks, an improvement that remained through the 16-week study period. The placebo group had a 9 percent reduction in symptoms. The findings appeared in May in the Journal of Psychiatric Research.

Study author M. Axel Wollmer, a psychiatrist at the University of Basel in Switzerland, believes the treatment “interrupts feedback from the facial musculature to the brain, which may be involved in the development and maintenance of negative emotions.” Past studies have shown that Botox impairs people's ability to identify others' feelings, and the new finding adds more evidence: the muscles of the face are instrumental for identifying and experiencing emotions, not just communicating them.

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4 octobre 2012 4 04 /10 /octobre /2012 12:15

Reprinted from Are We Getting Smarter? Rising IQ in the Twenty-First Century, by James R. Flynn. Copyright © 2012 James R. Flynn. Reprinted with the permission of Cambridge University Press.

The phenomenon of IQ gains has created unnecessary controversy because of conceptual confusion. Imagine an archaeologist from the distant future who excavates our civilization and finds a record of performances over time on measures of marksmanship. The test is always the same, that is, how many bullets you can put in a target 100 meters away in a minute. Records from 1865 (the U.S. Civil War) show the best score to be five bullets in the target, records from 1898 (Spanish-American War) show 10, and records from 1918 (World War I) show 50.

A group of "marksmanship-metricians" looks at these data. They find it worthless for measuring marksmanship. They make two points. First, they distinguish between the measure and the trait being measured. The mere fact that performance on the test has risen in terms of "items correct" does not mean that marksmanship ability has increased. True, the test is unaltered but all we know is that the test has gotten easier. Many things might account for that. Second, they stress that we have only relative and no absolute scales of measurement. We can rank soldiers against one another at each of the three times. But we have no measure that would bridge the transition from one shooting instrument to another. How could you rank the best shot with a sling against the best shot with a bow and arrow? At this point, the marksmanship-metrician either gives up or looks for something that would allow him to do his job. Perhaps some new data that would afford an absolute measure of marksmanship over time such as eye tests or a measure of steady hands.

However, a group of military historians are also present and it is at this point they get excited. They want to know why the test got easier, irrespective of whether the answer aids or undermines the measurement of marksmanship over time. They ask the archaeologists to look further. Luckily, they discover battlefields specific to each time. The 1865 battlefields disclose the presence of primitive rifles, the 1898 ones repeating rifles, and the 1918 ones machine guns. Now we know why it was easier to get more bullets into the target over time and we can confirm that this was no measure of enhanced marksmanship. But it is of enormous historical and social significance. Battle casualties, the industries needed to arm the troops, and so forth altered dramatically.

Confusion about the two roles has been dispelled. If the battlefields had been the artifacts first discovered, there would have been no confusion because no one uses battlefields as instruments for measuring marksmanship. It was the fact that the first artifacts were also instruments of measurement that put historians and metricians at cross-purposes. Now they see that different concepts dominate their two spheres: social evolution in weaponry—whose significance is that we have become much better at solving the problem of how to kill people quickly; marksmanship—whose significance is which people have the ability to kill more skillfully than other people can.

The historian has done nothing to undermine what the metrician does. At any given time, measuring marksmanship may be the most important thing you can do to predict the life histories of individuals. Imagine a society dominated by dueling. It may be that the lives of those who are poor shots are likely to be too brief to waste time sending them to university, or hire them, or marry them. If a particular group or nation lacks the skill, it may be at the mercy of the better skilled. Nonetheless, this is no reason to ignore everything else in writing military history.

Some years ago, acting as an archaeologist, I amassed a large body of data showing that IQ tests had gotten easier. Over the twentieth century, the average person was getting many more items correct on tests like Raven's and Similarities. The response of intelligence- org-metricians was dual [Editor's note: See here for an exploration of the "general intelligence" factor g]. First, they distinguished IQ tests as measuring instruments from the trait being measured, that is, from intelligence (or g if you will). Second, they noted that in the absence of an absolute scale of measurement, the mere fact that the tests had gotten easier told us nothing about whether the trait was being enhanced. IQ tests were only relative scales of measurement ranking the members of a group in terms of items they found easy to items they found difficult. A radical shift in the ease/difficulty of items meant all bets were off. At this point, the g-metrician decides that he cannot do his job of measurement and begins to look for an absolute measure that would allow him to do so (perhaps reaction times or inspection times).

However, as a cognitive historian, this was where I began to get excited. Why had the items gotten so much easier over time? Where was the alteration in our mental weaponry that was analogous to the transition from the rifle to the machine gun? This meant returning to the role of archaeologist and finding battlefields of the mind that distinguished 1900 from the year 2000. I found evidence of a profound shift from an exclusively utilitarian attitude to concrete reality toward a new attitude. Increasingly, people felt it was important to classify concrete reality (in terms the more abstract the better); and to take the hypothetical seriously (which freed logic to deal with not only imagined situations but also symbols that had no concrete referents).

It was the initial artifacts that caused all the trouble. Because they were performances on IQ tests, and IQ tests are instruments of measurement, the roles of the cognitive historian and the g-metrician were confused. Finding the causes and developing the implications of a shift in habits of mind over time is simply not equivalent to a task of measurement, even the measurement of intelligence. Now all should see that different concepts dominate two spheres: society's demands—whose evolution from one generation to the next dominates the realm of cognitive history; and g—which measures individual differences in cognitive ability. And just as the g-metrician should not undervalue the non-measurement task of the historian, so the historian does nothing to devalue the measurement of which individuals are most likely to learn fastest and best when compared to one another.

I have used an analogy to break the steel chain of ideas that circumscribed our ability to see the light IQ gains shed on cognitive history. I hope it will convince psychometricans that my interpretation of the significance of IQ gains over time is not adversarial. No one is disputing their right to use whatever constructs are best to do their job: measuring cognitive skill differences between people.

But an analogy that clarifies one thing can introduce a new confusion. The reciprocal causation between developing new weapons and the physique of marksmen is a shadow of the interaction between developing new habits of mind and the brain.

The new weapons were a technological development of something outside our selves that had minimal impact on biology. Perhaps our trigger fingers got slightly different exercise when we fired a machine gun rather than a musket. But the evolution from preoccupation with the concrete and the literal to the abstract and hypothetical was a profound change within our minds that involved new problem-solving activities.

Reciprocal causation between mind and brain entails that our brains may well be different from those of our ancestors. It is a matter of use and structure. If people switch from swimming to weight-lifting, the new exercise develops different muscles and the enhanced muscles make them better at the new activity. Everything we know about the brain suggests that it is similar to our muscles. Maguire et al. (2000) found that the brains of the best and most experienced London taxi-drivers had an enlarged hippocampus, which is the brain area used for navigating three-dimensional space. Here we see one area of the brain being developed without comparable development of other areas in response to a specialized cognitive activity. It may well be that when we do "Raven's-type" problems certain centers of our brain are active that used to get little exercise; or it may be that we increase the efficiency of synaptic connections throughout the brain. If we could scan the brains of people in 1900, who can say what differences we would see?

Do huge IQ gains mean we are more intelligent than our ancestors? If the question is "Do we have better brain potential at conception, or were our ancestors too stupid to deal with the concrete world of everyday life," the answer is no. If the question is "Do we live in a time that poses a wider range of cognitive problems than our ancestors encountered, and have we developed new cognitive skills and the kind of brain that can deal with these problems?," the answer is yes. Once we understand what has happened, we can communicate with one another even if some prefer the label "more intelligent" and others prefer "different." To care passionately about which label we use is to surrender to the tyranny of words. I suspect most readers ask the second question, and if so, they can say we are "smarter" than our ancestors. But it would probably be better to say that we are more modern, which is hardly surprising!

The theory of intelligence
The thesis about psychometics and cognitive history, that they actually complement one another, and the remarks made about the brain imply a new approach to the theory of intelligence. I believe we need a BIDS approach: one that treats the brain (B), individual differences (ID), and social trends (S) as three distinct levels, each having equal integrity. The three are interrelated and each has the right to propose hypotheses about what ought to happen on another level. It is our job to investigate them independently and then integrate what they tell us into a coherent whole.

The core of a BIDS approach is that each level has its own organizing concept and it is a mistake to impose the architectonic concept of one level on another. We have to realize that intelligence can act like a highly correlated set of abilities on one level (individual differences), like a set of functionally independent abilities on another level (cognitive trends over time), and like a mix on a third level (the brain), whose structure and operations underlie what people do on both of the other two levels. Let us look at the levels and their organizing concepts.

  • Individual differences: Performance differences between individuals on a wide variety of cognitive tasks are correlated primarily in terms of the cognitive complexity of the task (fluid g)—or the posited cognitive complexity of the path toward mastery (crystallized g). Information may not seem to differentiate between individuals for intelligence but if two people have the same opportunity, the better mind is likely to accumulate a wider range of information. I will call the appropriate organizing concept "General Intelligence" or g, without intending to foreclose improved measures that go beyond the limitations of "academic" intelligence (Heckman & Rubenstein, 2001; Heckman, Stixrud, & Urzua, 2006; Sternberg, 1988, 2006; Sternberg et al., 2000).
  • Society: Various real-world cognitive skills show different trends over time as a result of shifting social priorities. I will call this concept "Social Adaptation." As I have argued, the major confusion thus far has been as follows: either to insist on using the organizing concept of the individual differences level to assess cognitive evolution, and call IQ gains hollow if they are not g gains; or to insist on using the organizing concept of the societal level to discount the measurement of individual differences in intelligence (e.g. to deny that some individuals really do need better minds and brains to deal with the dominant cognitive demands of their time).
  • The brain: Localized neural clusters are developed differently as a result of specialized cognitive exercise. There are also important factors that affect all neural clusters such as blood supply, dopamine as a substance that render neurons receptive to registering experience, and the input of the stress-response system. Let us call its organizing concept "Neural Federalism." The brain is a system in which a certain degree of autonomy is limited by an overall organizational structure.

Researchers on this level should try to explain what occurs on both of the other two levels. The task of the brain physiologist is reductionist. Perfect knowledge of the brain's role would mean the following: given data on how cognition varies from person to person and from time to time, we can map what brain events underlie both social and life histories. To flesh this out, make the simplifying assumption that the mind performs only four operations when cognizing: classification or CL (of the Similarities sort); liberated logic or LL (of the Raven's sort); practical intelligence or PI (needed to manipulate the concrete world); and vocabulary and information acquisition or VI. And posit that the brain is neatly divided into four sectors active respectively when the mind performs the four mental operations; that is, it is divided into matching CL, LL, PI, and VI sectors.

Through magnetic resonance imaging scans (MRI) of the brain, we get "pictures" of these sectors. Somehow we have MRIs from 1900 that we can compare to MRIs of 2000. When we measure the neurons within the CL and LL sectors, we find that the later brains have "thickened" neurons. The extra thick­ness exactly predicts the century's enhanced performance on Similarities and Raven's.

As for individual differences, we have pictures of what is going on in the brains of two people in the VI sector as they enjoy the same exposure to new vocabulary. We note that the neurons (and connections between neurons) of one person are better nourished than those of the other because of optimal blood supply (we know just what the optimum is). We note that when the neurons are used to learn new vocabulary, the neurons of one person are sprayed with the optimum amount of dopamine and the neurons of the other are less adequately sprayed. And we can measure the exact amount of extra thickening of grey matter the first person enjoys compared to the second. This allows us to actually predict their different performances on the WISC Vocabulary subtest.

Given the above, brain physiology would have performed its reductionist task. Problem-solving differences between individuals and between generations will both have been reduced to brain functions. It will explain both the tendency of various cognitive skills to be correlated on the individual differences level, and their tendency to show functional autonomy on the societal level. That does not, of course, mean that explaining human cognition on the levels of individual differences or social demands have been abolished. Even if physiology can predict every right and wrong answer of people taking IQ tests, no one will understand why these tests exist without knowing that occupation is dependent on mastering certain cognitive skills (social level) and that parents want to know whether their children have those skills (individual differences).

Closing windows
IQ trends over time turn the pages of a great romance: the cogni­tive history of the twentieth century. I may have made mistakes in interpreting their significance, but I hope I have convinced you that they are significant. Those who differ about that must, in my opinion, assert one or both of two propositions. That since IQ tests measure g, they cannot possibly signal the ebb and flow of anything else. I doubt anyone will defend that proposition. That nothing save g, or the special factors that fit under the umbrella of g, interests them. I believe that some feel that way, which is sad. They will always view the history of cognition through one window.

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4 octobre 2012 4 04 /10 /octobre /2012 12:09

Introduction
Have you ever been playing cards and wished you could use psychic powers to draw the card you wanted? You may not be psychic, but you can still have the power of probability on your side. In this activity you'll investigate the probabilities of drawing specific types of cards from a deck. You'll discover how math can help you avoid the dreaded phrase, "Go fish!"

Background
When you draw a card from a deck, you have a certain chance of getting a specific type of card, such as a spade or face card, or one particular card, such as the queen of hearts. Consider the game "Go Fish" with a regular card deck. The goal is to get the most four-of-a-kind sets by asking your opponent for matching cards or by drawing them from the deck. To win, you can rely on chance or you can increase your probability of getting matching cards, but how?

By understanding how chance is related to math, you can play with a winning strategy. For example, if you have three kings and one queen in your hand and it's your turn to ask for a card, which one should you ask your opponent for? You might think you should ask for a king, but it's actually better to take a queen! Why? Because you have a better chance of getting it. There are four kings and four queens in the deck, and with three kings and one queen in your hand, there's one king and three queens left. This gives you only one chance to get a king, but three chances to get a queen out of the remaining cards.

Materials
•     Standard deck of playing cards
•     Piece of paper
•     Pencil or pen
•     Calculator

Preparation
•     Count the cards in the deck and make sure it is complete. (There should be 54 cards total.) Take out the two jokers. Shuffle the deck three times and set aside.
•     Pick four types of cards to investigate, such as a color, suit, number or face card, and a specific one. For example, you could investigate red cards, spades, kings and the queen of hearts.
•     Draw a table to in which to record your data. Make a column for each card type you'll investigate. In the first row write how many of that type of card are in the deck. For example, there are 26 red cards in a deck, 13 spades, four kings and one queen of hearts. Make 10 rows below this one for the 10 trials you will be doing.

Procedure
•     Decide which type of card you will investigate first. Draw cards from the top of the deck and flip them over one at a time, counting as you go, and stop when you see that type of card. How many cards did you draw until you reached that card? Write down the answer in your table.
•     Shuffle the deck again and repeat this process, flipping over the cards and looking for the same type of card. How many cards did it take this time? Write down the answer in your table. Repeat this for a total of 10 times for one type of card.
•     Repeat this process for each of the four types of cards you picked to investigate. This means that you will have looked for each type of card a total of 10 times.
•     Calculate the average number of cards you drew to reach each type of card. Label the last row in your table "Averages" and write them in this row.
•     Which types of cards were the easiest to draw? Which were the most difficult? How do you think the chances of drawing a card relate to the total number of that card type in the deck? 
•     Based on what you saw in this activity, how do you think probability can help you choose the right strategy in a card game?
•     Extra: A more advanced way of showing the results of your experiment would be to make histograms, which are a type of graph to show distributions. Try making a separate histogram for each type of card you tested by graphing the number of cards drawn for each trial separately in a bar graph. When all of the bars are lined up next to each other, what does the overall shape of the distribution look like?
•     Extra: The probability of drawing a particular type of card also depends on the number of cards drawn each time. Try doing this activity again but draw samples of three, five or seven cards at a time. Do your chances improve as more cards are taken?
•     Extra: Probabilities can change your strategies for playing a card game. Can you design an experiment to show how probabilities can help you choose cards and win "Go Fish"? What about other popular card games? Can you invent your own game based on probabilities?


Observations and results
Did it take fewer draws to reach a certain color than it took to reach a certain suit or kind of card? Did it take even more draws to reach a specific card?

Mathematicians measure probability by counting and using some very basic math, like addition and division. For example, you can add up the number of spades in a complete deck (13) and divide this by the total number of cards in the deck (52) to get the probability of randomly drawing a spade: 13 in 52, or 25 percent. If you were investigating red cards, kings or the queen of hearts, the odds of randomly drawing one of these from a complete deck are 50 percent (26 in 52); about 7.7 percent (four in 52); or about 1.9 percent (one in 52), respectively. This is why, on average (when done over enough trials), it is easier to draw a red card than a spade, a spade than a king, and a king than the queen of hearts. As you draw cards from a deck, the odds of finding your card change. For example, if you are looking for a spade and do not get it on your first draw, there are still 13 spades in the deck but the deck now holds only 51 cards, so your odds of drawing a spade on the second draw are 13 in 51, or about 25.5 percent. This may not seem like much of an improvement, but with every draw the odds continue to increase.

More to explore
Unraveling Probability Paradoxes from Scientific American
Calculating the Probability of Simple Events from neoK12
4 Great Math Games from Scholastic, Inc.
Classified Index of Card Games from John McLeod
Pick a Card, Any Card from Science Buddies

This activity brought to you in partnership with Science Buddies

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4 octobre 2012 4 04 /10 /octobre /2012 12:04

How much is too much chocolate? Desperately devouring 5 percent of one's body weight might sound extreme, but scientists tinkering with the brain chemistry of rodents have found it's certainly possible.

Scientists at the University of Michigan (U.M.) have identified how a brain region plays a role in our pursuit of sweet temptations. As they describe in the September 20 issue of Current Biology, a surge of chemical compounds resembling opium in this area can trigger the impulse to gorge on a treat without restraint.

The region in question is the neostriatum. In humans this area is split into two parts, behind the eyes and below the folds of the cortex near the front of the head. It's just above the brain's well-studied reward circuitry, which includes the ventral striatum and nucleus accumbens. Traditionally, the neostriatum has been studied in movement and habitual motor behaviors. Although no previous research had found a clear causal link between the region and motivation to eat, some human studies with functional magnetic resonance imaging have suggested that the neostriatum is active when an overweight subject looks at food or an addict views a drug of choice.

To investigate the brain region further, the researchers studied changes in the neostriatum chemistry of lab rats when at rest, hungry, offered food, feeding and after eating. The proffered food was chocolate, specifically M&Ms. Author and biopsychologist Alexandra DiFeliceantonio at U.M. says, "Chocolate offers sweetness and fattiness—the perfect storm of a stimulus to get the effect we wanted."

Using a catheter, the researchers sampled fluid from the neostriatum during these stages to discern neurotransmitter activity. They observed a pronounced spike in one neurotransmitter in particular—enkephalin—when rats began feeding. Enkephalin, like the neurotransmitter endorphin, is an opioid that sends out pleasurable signals. The scientists observed that the stronger the enkephalin rise, the faster the rats raced to eat M&Ms.

Eventually—after having wolfed down about 10 M&Ms each in 20 minutes—normal rats became sated and ceased eating. With this change, the enkephalin rush abated while other circuitry presumably kicked in to tell the brain to stop the compulsion.

In the hopes of finding a directional link between the neostriatum's opioid receptors and feasting, the researchers injected an artificial opioid straight into the neostriatum. When they proffered the rats M&Ms, a feeding frenzy began again, but this time most of the animals gobbled more than 17 of the candies each. Given their slight sizes, this is comparable to a 68-kilogram human eating three kilograms of chocolate within an hour.

The ravenous episode was so intense that the rats showed no signs of stopping and had to be forcibly removed from the feast. In addition, opioid-injected rats gobbled chocolate faster, as though the drugged subjects were more desperate to begin with. Opioid injections to neighboring brain regions, or injections with other chemicals, produced a much weaker response. This led the researchers to believe that the neostriatum's opioid receptors activate an intense motivational system, driving the rats to pursue rewards.

In a final test, the researchers decided to evaluate whether the neostriatum's neurotransmitter spike actually enhanced the way rats were attracted to their food—somehow magnifying the experience of a rich, chocolatey taste. To do this, they offered rats injected with or without the opioid a taste of chocolate or sweet oral infusion. They then measured how much a rat liked the taste by counting lip-licking, a common behavioral test of taste preference in babies and nonhuman primates. They found that the opioid-dosed rats did not appear particularly enthused about chocolate's sweet flavor—they did not lick their lips more when exposed to a sweet after the injection. The researchers concluded that their overindulgence was based purely on compulsion and not the candy's intensified deliciousness.

The finding suggests that flooding the neostriatum's receptors with opioids—natural or not—can drive extreme overeating. The region's proximity to the brain's pleasure network means the work can have implications for other enjoyable activities and vices. "These areas work together in concert and create these seas of wanting in the brain," DiFeliceantonio says.

"This study is adding another piece to the puzzle of how the reward system works," says neuroscientist Gary Wenk at The Ohio State University. Wenk, who was not involved in the study, explains that evolutionary reasons can help us understand why our brain pushes us to overeat: "We evolved so that when we found food, we would eat as much as we could." Not only would this ensure that we received necessary nutrients, it kept competitors from stealing our meals—we'd leave nothing for them to take. The brain helps by activating the opiate system as a euphoric reward, counteracting the discomfort of a swelling waist and encouraging us to have one more bite.

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4 octobre 2012 4 04 /10 /octobre /2012 11:56

The laughter of tiny babies is not just a phenomenally popular theme for YouTube videos, it is also a fantastic window into the workings of the human brain. You can’t laugh unless you get the joke. At the University of London's Birkbeck Babylab we study how babies learn about the world. We believe that studying early laughter in detail will throw new light on the workings of babies’ brains, as well as offering new insights into the uniquely human characteristic that is humor.

We are researching just what makes babies laugh by conducting the largest ever global survey of early laughter. If you are parent with a child under two, you can take the survey. It takes about 15-20 minutes to complete.

We are also interested on particular incidents that made your baby laugh. Who was present? What was so funny? You can file a 'field report'.

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