Om cykelhjelme og The Culture of Fear.

Er cykelhjelme en bluff?

Interessant svensk artikel om cykelhjelme:
http://ettlivutanbil.wordpress.com/2010/12/04/ar-cykelhjalm-en-bluff/

Cykelhjelmsatire

"Min mor tvinger mig til at tage den på"






"Now you're ready to play freely"




Tegneserie karakterer. Forældrene er overbeskyttende - og til grin.

Hjelmpåbud fører til færre cyklister

En ny papir om de negative konsekvenser af hjelmtvang/påbud af cykelhjelm. Den handler især om hvordan hjelmtvang er skyldig i et fald af antallet af cyklister, især børn. Ikke noget nyt. Det er set i alle de steder i verdenen hvor cykelhjelme er blevet promoveret. Men interessant læsning.

Her kan du se hvor galt det er gået i Sverige i denne artikel fra Copenhagenize.com. Antallet af børn der cykler er faldet drastisk siden cykelhjelm promovering begyndt.

Anyway:

Helmet compulsion leads to less cycling, say economists:

Mandatory helmet laws have "unintended consequences" says paper to be published in US Journal of Law and Economics

According to a forthcoming study in the Journal of Law and Economics, bicycle helmet compulsion for children brings with it a likely drop in the amount of youth cycling. Children don't exercise any less, finds the study, but children ditch cycling and switch to other sports and activities.

The study - Intended and Unintended Consequences of Youth Bicycle Helmet Laws [PDF] - is by economists Christopher S. Carpenter of the Merage School of Business at the University of California, and Mark F. Stehr of the LeBow College of Business at Drexel University.

The professors show that, in America, 650,000 fewer children ride bikes each year after helmet laws go into effect.

"As other states consider helmet laws as a way to reduce bicycling related injuries and fatalities, they should keep in mind that although the laws increase helmet use and reduce fatalities, they are also likely to reduce bicycling among the targeted group," says the study.

The professors conclude that "in addition to the increase in helmet use, there is also robust evidence for an unintended and previously undocumented mechanism: helmet laws produced modest but statistically significant reductions in youth bicycling participation of 4-5 percent…[but that] it is likely that overall bicycling miles travelled fell even more."

An emotive argument used often for cycle helmet compulsion is: "If legislation can save just one life, it will be worth it."

Helmet law opponents say that such an argument could be equally applied to compulsory helmets for child soccer players, pedestrians, and children ferried around in cars, all activities that have seen child fatalities caused through head injuries.

Via Bike Biz

Cykelhjelm .org

Mindre viden, mere angst - mere viden, mindre angst

Læs cykelhjelm og alt muligt andet når du læser det her:


War and terrorism, anthrax and SARS, the stock market and the job market — if any of those things have really shaken you up, that's your amygdala talking to you.

The amygdala (pronounced ah-MIG-da-la) is a region of the brain that, as one researcher put it, tells you if new sights and sounds are "relevant" to you — whether you need to respond quickly to them. The amygdala can generate powerful emotions — the so-called fight-or-flight response.

Another region of the brain, the prefrontal cortex, is the center of reflection, the section the brain uses to make reasoned responses. Still other regions help one recall an experience, or calculate its importance.

The problem is that when one needs to react quickly to something traumatic, the amygdala wins out. And that means, sometimes, that people worry about the wrong things.

"We all make poor decisions at times because we don't have enough information, or we react impulsively," says Jordan Grafman of the National Institute of Neurological Disorders and Stroke.

Knowing Your Risks

Grafman's research includes extensive work with a Vietnam veteran he calls Michael. Michael was a very levelheaded man, until a war injury damaged his prefrontal cortex.

After that, says Grafman, he became an uncontrolled risk-taker. He was impulsive. He married a prostitute, then an underage woman. Signals from his amygdala, Grafman theorizes, went unchecked. Only after extensive therapy has Michael been able to hold down a job.

Michael's experience is an extreme case, but Grafman says it shows us how the human brain is designed to react first and reason later.

"It's our natural tendency to look toward things that in essence turn us on, appeal to us or sometimes make us quite fearful," says Grafman. "But that very design often distorts the actual risk of the circumstance."

Behavioral scientists say because of the brain's structure, perfectly healthy people may overreact to upsetting circumstances. Many Americans went and bought duct tape — even though they knew, on an intellectual level, that their personal odds of dying in a terrorist attack were far smaller than the risk from auto accidents or heart disease.

From Main Street to Wall Street

At the Massachusetts Institute of Technology, economist Andrew Lo sees the same dynamic at work in financial markets.

"We're hoping this will suggest broader implications for how it is people think about risks in general," says Lo.

As part of their research, Lo and his assistants attached electrodes to Linda Sarkisian, a stock trader in Boston. They measured her heart rate, perspiration and brain waves as she maneuvered through the ups and downs of the market.

"Oh, your heart's beating like crazy now," said one of her colleagues as they executed trades. "You're making money!"

Lo says his research is only in its early stages, but he says that if traders follow their instincts, they will quickly lose money. They will buy stocks when they look "good" — that is, when their prices are high — and sell in a panic after the market has gone down.

"Whereas the fight-or-flight response will help you save your life in certain situations," Lo says, "in the financial context it will not help you save your wealth."

And that leads, perhaps, to a larger theme: that the decisions we all have to make on impulse are often the wrong ones. Doctors say that after a traumatic experience, the best response is often to do nothing — to wait, calm down, and learn more.

"Less knowledge, more anxiety," says Grafman. "More knowledge, less anxiety."


http://abcnews.go.com/WNT/story?id=129714&page=1

Vi er herredårlige til risikovurdering

Culture of Fear artikel fra New York Times.

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You read the news about that poor football player, right? The University of Pennsylvania lineman who killed himself? And the autopsy, which showed that his head had been rattled by all those blows over the years? And the fact that the damage may have caused depression and lack of impulse control, which may have resulted in his suicide?

Now, what do you do with this information?

Whether the growing attention to concussions in young athletes will lead to an exodus from the football field (or the basketball court, or the hockey rink) will say a lot about how we humans process risk. Which means it’s anybody’s guess.

If history is any guide, we seem to veer between overreaction and underreaction — all while defining our own response as “moderate.” There is an inherent hypocrisy in our attempts to control our odds — putting the organic veggies (there is no actual data proving that organic foods increase longevity) in the trunk of our car (researchers tell us there is “evidence” but not “proof” that car emissions accelerate heart disease), then checking our e-mail on our cellphone at the next red light (2,600 traffic deaths a year are caused by drivers using cellphones, according to a Harvard study).

And while we certainly make constant (mis)calculations in our adult lives, we seem all the more determined yet befuddled when it comes to the safety of our children. For instance, the five things most likely to cause injury to children up to age 18, according to the Centers for Disease Control and Prevention, are: car accidents, homicide (usually at the hands of someone they know), child abuse, suicide or drowning. And what are the five things that parents are most worried about (according to surveys by the Mayo Clinic)? Kidnapping, school snipers, terrorists, dangerous strangers and drugs.

“Parents are just bad at risk assessment,” said Christie Barnes, a mother of four and the author of “The Paranoid Parents Guide.” “We are constantly overestimating rare dangers while underestimating common ones.”

We probably do this because our brains are not designed to process abstract or long-term risk. We were built to hear a sound, determine whether it is the growl of a saber-tooth, and then decide to run or go back to sleep. But in a world where you can hear the roar of what may or may not be a tiger (or a kidnapped child) in Montana while you are sitting in your kitchen in Florida, it’s tough to assess personal danger. With worst-case scenarios being thrown our way hourly on TV and the Internet, our sense of proportion and ratio becomes muddled.

“The least safe thing you can do with your child, statistically, is drive them somewhere,” said Lenore Skenazy, author of “Free-Range Kids,” a manifesto preaching a return to the day when children were allowed to roam on their own. “Yet every time we put them in the car we don’t think, ‘Oh God, maybe I should take public transportation instead, because if something happened to my kid on the way to the orthodontist I could never forgive myself.’ ”

So we put them in that car and we drive — to the orthodontist, to school, to their friend’s house two blocks away — because “if I let them walk and they were abducted I would never forgive myself.” This despite the fact that the British writer Warwick Cairns, author of “How to Live Dangerously,” has calculated that if you wanted to guarantee that your child would be snatched off the street, he or she would have to stand outside alone for 750,000 hours. And while we are busy inflating some risks, we tend not to focus on others — like the obesity and diabetes that result when children are driven someplace when they could walk, or when they play video games inside instead of playing in the park.

Perversely, our worry seems to be increasing at a time when actual risk is decreasing. “Homicide is down, kidnapping is down, traffic deaths are down,” Ms. Barnes said. What is up, however, is measurement. It seems as if there’s a statistic for everything, and many of the numbers change from one study to the next. This means we are increasingly being asked to be expert in areas where even the experts aren’t certain.

The onslaught of numbers also leads us to whittle risk into tiny increments. “A kid growing up has to go through seven different changes of car seat by law in some states,” said Dr. Daniel Perl, a professor of pathology at Uniformed Services University of the Health Sciences in Bethesda, Md., the medical school for the United States military, “and what that prevents in terms of injuries or deaths are probably a couple of handfuls. Yet we have over four million kids playing football. Moms will take their 7-year-olds in the car, in a state-of-the-art car seat, to go and play football.”

Which brings us back to the beginning.

There is no question that children get hurt playing football. The sport accounts for 22 percent of all concussions among 8- to 19-year-olds; 27 percent of football players ages 12 through 17 have had a least one concussion. That will not be news to any mother who has squinted through her fingers as her son is tackled on a Saturday afternoon. What will be news, though, is last week’s link between teenage football and chronic traumatic encephalopathy, which is what Boston University researchers found in the brain of Owen Thomas, 21, the Penn student who killed himself in April.

So far, there is only one case. Still, what is a parent to do? “Some people may look at this study and say, ‘That’s it, Johnny; you’re taking up chess,’ ” said Dr. Perl, who stressed that he was speaking as an experienced neuropathologist and not on behalf of the Department of Defense.

On the other hand, he notes, the existing data on athletes with C.T.E. consists of 51 autopsies, most of those on boxers, not football players. And there are benefits to football — the feeling of belonging to a team, the physical exercise, the potential college scholarship, perhaps the pride in carrying on a family tradition — that will outweigh the risks for some families, assuming those risks can ever actually be quantified.

“Right now I don’t know that it’s calculable, but it’s estimatable,” Dr. Perl said, adding that he wouldn’t venture to make an estimate. “And you can’t really make a recommendation based on one case. So it’s up to a young player’s parents to decide.”

A version of this article appeared in print on September 19, 2010, on page WK4 of the New York edition.

Fornuftig cykelhjelm debat i Australien

I denne artikel fra Australien kan man se at debatten er på et langt højere niveau end i Danmark.

Head Case

Bill Curnow, the president of the Cyclists Rights Action Group in Canberra, reviewed the scientific literature for a 2008 book, Transport Accident Analysis and Prevention, and concluded science had not been applied to assess the efficacy of helmets to protect the brain, against diffuse injury in particular, arguing the medical profession and helmet industry have been "unduly influential" in the introduction of compulsory helmet wearing.

Scientific circles had "widely discredited" the theory that linear acceleration is the main cause of brain injury, yet helmet makers had made a huge investment in this theory and designed their helmets accordingly, says Curnow, while ignoring the role of angular acceleration in causing brain injury, due to rotation of the head.