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Read more of this story at Slashdot.

The world's first vaccine designed to prevent cancer was not developed by a pharmaceutical company. Instead, its development was funded by public institutions on two continents, including three universities, and the U.S. National Cancer Institute. The vaccine prevents human papillomavirus (HPV), an ailment that can lead to deadly cervical cancer. HPV is spread through sexual contact, and 80% of males and females become infected during their lifetimes. But, thanks the to HPV vaccine, it doesn't have to be that way anymore.

How the HPV vaccine works

The HPV vaccine relies on virus-like particles (VLPs). The VLPs in the HPV vaccine share the same outer protein coat (L1) as human papillomavirus, however, the VLPs do lack the genetic material in HPV necessary to infect a human. The outer protein coat is the key to how the vaccine works. Thanks to the protein coat, the VLPs can assemble in the same way as HPV, and this structural similarity allows the components of the vaccine to produce an immune response without subjecting the patient to the virus in any way. It's not a neutered or dead form of the virus as in the influenza vaccine - it's no virus at all.

3 schools, 4 research groups, & (at least) 4 patents

The creation of the HPV vaccine was an effort two decades in the making. Researchers at Georgetown University are credited with the dominant patent for the the HPV vaccine due to their initial background research, however, the Georgetown team never worked with the virus-like particles. The Georgetown University group showed that the native conformation (the normal form) of L1 protein coat was needed to allow virus-like particles to form.

The U.S. Patent Office also recognizes patent claims from the U.S. National Cancer Institute, the University of Queensland, and the University of Rochester. Researchers at the University of Queensland published data with two different types of protein coats, L1 and L2, and noted that these coats allowed the assembly of virus like particles, but these virus like particles were small and not correctly assembled. This finding pre-dated the Georgetown University publication, and has spurred some controversy concerning the dominant patent.

Researchers at the National Cancer Institute, a branch of the NIH separate and apart from universities, were the first to produce an active virus-like particle that produced an immune response in animals. The NCI researchers also determined that other researchers had been using a mutant of the major HPV L1 capsid, causing slight changes in the manner in which the VLPs formed, thus refining the process.

The University of Rochester team was responsible for the first studies showing an immune response in humans. The University of Queensland research was pioneered by Dr. Ian Frazer in Australia, and sold partial patents to Merck and an Australian company CSL Limited to finance their research and clinical trials. The teams at Georgetown University and the University of Rochester were funded through grants from the National Cancer Institute.

These four groups may not have worked jointly, however, their work (and possible academic rivalry) combined with public funding allowed for quick and efficient discovery and optimization of the VLPs, as most of the major research findings paving the way for the HPV vaccine occurred between 1991 and 1993.

Two versions of the vaccine

Gardisil, the first HPV vaccine on the market, is manufactured by Merck and protects against four different strains of HPV. This protection covers HPV-16 and HPV-18, with these causing 70% of cervical cancer cases, cases which kill as many as 300,000 women annually. HPV-16 has also been linked to oropharyngeal cancer. Gardisil also protects against HPV-6 and HPV-11, guarding against 90% of genital warts. Protection against general warts and a recent FDA statement showing Gardisil to prevent anal and oropharyngeal cancer has increased demand amongst both males and females.

Cervarix, produced by GlaxosmithKline and approved for use in the United States in 2009 after several years of use in other areas of the world, protects only against HPV-16 and HPV-18, and thus lacks protection against genital warts. Despite this lack of protection against the physical attributes of sexually transmitted disease, one recent National Cancer Institute study showed that two of the mandated three shots of Cervarix may be sufficient for protection. This is quite the finding, as the third dose is taken six months after the initial injection, and likely to be skipped by the patient. Additionally, Cevarix has been shown to be effective over 7 years after administration.

Arguing against the HPV Vaccine

The suggestion that boys and young men receive the HPV vaccine has been met with controversy. Dr. William Schaffner, chairman of the Department of Preventive Medicine at Vanderbilt University School of Medicine, recently stated his support for administering the vaccine to boys and young men, emphasizing how far basic research has come:

This is cancer, for Pete's sake […] A vaccine against cancer was the dream of our youth.

You might not like shots, but it's hard to argue against getting the HPV vaccine. There is no dead or neutered virus involved - there is no genetic material in the vaccine at all. The HPV vaccine a great example of public funding and several universities putting the parts together quickly and saving many lives in the process.

Images courtesy of the World Health Organization, Medscape, and GlaxoSmithKline. Sources linked within article.

The world's first vaccine designed to prevent cancer was not developed by a pharmaceutical company. Instead, its development was funded by public institutions on two continents, including three universities, and the U.S. National Cancer Institute. The vaccine prevents human papillomavirus (HPV), an ailment that can lead to deadly cervical cancer. HPV is spread through sexual contact, and 80% of males and females become infected during their lifetimes. But, thanks the to HPV vaccine, it doesn't have to be that way anymore.

How the HPV vaccine works

The HPV vaccine relies on virus-like particles (VLPs). The VLPs in the HPV vaccine share the same outer protein coat (L1) as human papillomavirus, however, the VLPs do lack the genetic material in HPV necessary to infect a human. The outer protein coat is the key to how the vaccine works. Thanks to the protein coat, the VLPs can assemble in the same way as HPV, and this structural similarity allows the components of the vaccine to produce an immune response without subjecting the patient to the virus in any way. It's not a neutered or dead form of the virus as in the influenza vaccine - it's no virus at all.

3 schools, 4 research groups, & (at least) 4 patents

The creation of the HPV vaccine was an effort two decades in the making. Researchers at Georgetown University are credited with the dominant patent for the the HPV vaccine due to their initial background research, however, the Georgetown team never worked with the virus-like particles. The Georgetown University group showed that the native conformation (the normal form) of L1 protein coat was needed to allow virus-like particles to form.

The U.S. Patent Office also recognizes patent claims from the U.S. National Cancer Institute, the University of Queensland, and the University of Rochester. Researchers at the University of Queensland published data with two different types of protein coats, L1 and L2, and noted that these coats allowed the assembly of virus like particles, but these virus like particles were small and not correctly assembled. This finding pre-dated the Georgetown University publication, and has spurred some controversy concerning the dominant patent.

Researchers at the National Cancer Institute, a branch of the NIH separate and apart from universities, were the first to produce an active virus-like particle that produced an immune response in animals. The NCI researchers also determined that other researchers had been using a mutant of the major HPV L1 capsid, causing slight changes in the manner in which the VLPs formed, thus refining the process.

The University of Rochester team was responsible for the first studies showing an immune response in humans. The University of Queensland research was pioneered by Dr. Ian Frazer in Australia, and sold partial patents to Merck and an Australian company CSL Limited to finance their research and clinical trials. The teams at Georgetown University and the University of Rochester were funded through grants from the National Cancer Institute.

These four groups may not have worked jointly, however, their work (and possible academic rivalry) combined with public funding allowed for quick and efficient discovery and optimization of the VLPs, as most of the major research findings paving the way for the HPV vaccine occurred between 1991 and 1993.

Two versions of the vaccine

Gardisil, the first HPV vaccine on the market, is manufactured by Merck and protects against four different strains of HPV. This protection covers HPV-16 and HPV-18, with these causing 70% of cervical cancer cases, cases which kill as many as 300,000 women annually. HPV-16 has also been linked to oropharyngeal cancer. Gardisil also protects against HPV-6 and HPV-11, guarding against 90% of genital warts. Protection against general warts and a recent FDA statement showing Gardisil to prevent anal and oropharyngeal cancer has increased demand amongst both males and females.

Cervarix, produced by GlaxosmithKline and approved for use in the United States in 2009 after several years of use in other areas of the world, protects only against HPV-16 and HPV-18, and thus lacks protection against genital warts. Despite this lack of protection against the physical attributes of sexually transmitted disease, one recent National Cancer Institute study showed that two of the mandated three shots of Cervarix may be sufficient for protection. This is quite the finding, as the third dose is taken six months after the initial injection, and likely to be skipped by the patient. Additionally, Cevarix has been shown to be effective over 7 years after administration.

Arguing against the HPV Vaccine

The suggestion that boys and young men receive the HPV vaccine has been met with controversy. Dr. William Schaffner, chairman of the Department of Preventive Medicine at Vanderbilt University School of Medicine, recently stated his support for administering the vaccine to boys and young men, emphasizing how far basic research has come:

This is cancer, for Pete's sake […] A vaccine against cancer was the dream of our youth.

You might not like shots, but it's hard to argue against getting the HPV vaccine. There is no dead or neutered virus involved - there is no genetic material in the vaccine at all. The HPV vaccine a great example of public funding and several universities putting the parts together quickly and saving many lives in the process.

Images courtesy of the World Health Organization, Medscape, and GlaxoSmithKline. Sources linked within article.

After 1978, two strangely related things happened: a new set of regulations for processed meat limited the amount of nitrite used in hot dogs, forcing manufacturers to add ascorbate or erythorbate instead. And the following that year, there was a major dropoff in colon cancer deaths. Now, researchers are questioning the link between the two.

Nitrite preserved processed meats are loaded with nonvolatile N-nitroso compounds, but the addition of ascorbate and erythorbate replaced them, with only 1/90th of the amount remaining afterwards. There has been a significant amount of work on the link to processed meat with colorectal cancer, especially with the presence of nitrates and nitrites. The thing is that if this correlation was iron clad, then the there would have been a huge drop in the incidence of the cancer with the government regulation. Instead, there's been a major drop in the deaths from the disease — which is something very different. So while fewer people are dying of colon cancer, the drop in nitrites doesn't seem to have meant fewer people getting it.

"The drop in N-nitroso compound content caused by the mandated changes in processed meat should have been accompanied by a drop in the incidence of colon cancer," said Professor Sidney S. Mirvish, and the reduction in deaths "may have been due mostly to earlier detection and better treatment of this disease."

UPDATE: An earlier version of this article significantly misinterpreted part of the study — which was my mistake. It has been updated and corrected. Apologies.

Photo by Kenneth Sponsler via Shutterstock

After 1978, two strangely related things happened: a new set of regulations for processed meat limited the amount of nitrite used in hot dogs, forcing manufacturers to add ascorbate or erythorbate instead. And the following that year, there was a major dropoff in colon cancer deaths. Now, researchers are questioning the link between the two.

Nitrite preserved processed meats are loaded with nonvolatile N-nitroso compounds, but the addition of ascorbate and erythorbate replaced them, with only 1/90th of the amount remaining afterwards. There has been a significant amount of work on the link to processed meat with colorectal cancer, especially with the presence of nitrates and nitrites. The thing is that if this correlation was iron clad, then the there would have been a huge drop in the incidence of the cancer with the government regulation. Instead, there's been a major drop in the deaths from the disease — which is something very different. So while fewer people are dying of colon cancer, the drop in nitrites doesn't seem to have meant fewer people getting it.

"The drop in N-nitroso compound content caused by the mandated changes in processed meat should have been accompanied by a drop in the incidence of colon cancer," said Professor Sidney S. Mirvish, and the reduction in deaths "may have been due mostly to earlier detection and better treatment of this disease."

UPDATE: An earlier version of this article significantly misinterpreted part of the study — which was my mistake. It has been updated and corrected. Apologies.

Photo by Kenneth Sponsler via Shutterstock

The National Institutes of Health estimate that one out of every five persons in the US suffers from dyslexia, a brain-based learning disability that can make it frustratingly difficult to read. One way people have tried combatting the symptoms of dyslexia is with fonts like Dyslexie (pictured here), which are specially designed to decrease the number of errors made by dyslexics while reading.

Dyslexie was created by Christian Boer, a dyslexic graphic designer from the Netherlands. The font incorporates a number of typographical features that make it harder for the brains of dyslexics to rotate, swap, mirror, and otherwise confuse letters while they're reading.

Take the letters "p," "b" and "d," for example, depicted up top in Boer's Dyslexie typeface. In many fonts, these letters look very much the same, such that by rotating and mirroring them they can be used more or less interchangeably.

In Boer's font, however, the boldness of each letter's base is increased, granting each character a "weight" that hints at its proper orientation. Notice also that the space enclosed by each letter (what is referred to in typography as a character's "bowl" or "loop") is shaped just a little differently than that of the other two. These subtle typographical cues may not seem like much, but they go a long way in helping your brain recognize which letters belong where when they appear in words and sentences.

Learn more about the design of Dyslexie (including a slide show comparing different Dyslexie characters to those of other fonts) in this article by Scientific American's Jennifer Nalewicki. You can also try Dyslexie out for yourself by reading this version of Nalewicki's article.

[Via Scientific American]
Dyslexie characters by Christian Boer via SA

The National Institutes of Health estimate that one out of every five persons in the US suffers from dyslexia, a brain-based learning disability that can make it frustratingly difficult to read. One way people have tried combatting the symptoms of dyslexia is with fonts like Dyslexie (pictured here), which are specially designed to decrease the number of errors made by dyslexics while reading.

Dyslexie was created by Christian Boer, a dyslexic graphic designer from the Netherlands. The font incorporates a number of typographical features that make it harder for the brains of dyslexics to rotate, swap, mirror, and otherwise confuse letters while they're reading.

Take the letters "p," "b" and "d," for example, depicted up top in Boer's Dyslexie typeface. In many fonts, these letters look very much the same, such that by rotating and mirroring them they can be used more or less interchangeably.

In Boer's font, however, the boldness of each letter's base is increased, granting each character a "weight" that hints at its proper orientation. Notice also that the space enclosed by each letter (what is referred to in typography as a character's "bowl" or "loop") is shaped just a little differently than that of the other two. These subtle typographical cues may not seem like much, but they go a long way in helping your brain recognize which letters belong where when they appear in words and sentences.

Learn more about the design of Dyslexie (including a slide show comparing different Dyslexie characters to those of other fonts) in this article by Scientific American's Jennifer Nalewicki. You can also try Dyslexie out for yourself by reading this version of Nalewicki's article.

[Via Scientific American]
Dyslexie characters by Christian Boer via SA

Drinking can wreak havoc on your insides, and not just the relatively short-lived brand of havoc brought on by a one-night drinking spree. We're talking long-term damage to the mucous membrane of your stomach that can give rise to all manner of gastrointestinal disorders, including ulcers, colorectal cancer, and inflammatory bowel disease.

Now a team of European scientists has found that strawberries can help mitigate the stomach-punishing effects of alcohol consumption, and could even help improve the treatment of stomach ulcers.

Sara Tulipani, researcher at the University of Barcelona and co-author of the study, explains that "the positive effects of strawberries are not only linked to their antioxidant capacity and high content of phenolic compounds, but also to the fact that they activate the antioxidant defenses and enzymes of the body."

Translation? Gastrointestinal diseases like stomach ulcers are caused in part by what are known as free radicals, which are atoms and molecules with unpaired electrons. The fact that these chemicals have unpaired electrons makes them unstable and highly reactive. In an attempt to regain stability, these free radicals will react with and try to nab electrons from other, normal molecules, giving rise to damaging chain reactions in your cells that accumulate over time.

Free radicals are the byproducts of oxidation reactions that go on inside your body; so when when Tulipani talks about the "antioxidant capacity" of strawberries, or their ability to activate the antioxidant defenses of the body, she's talking about their ability to inhibit the oxidation of other molecules, and, by extension, the production of harmful free radicals.

Finally, the phenolic compounds Tulipani is referring to are called anthocyanins (the same class of molecules that causes leaves to appear red during autumn), which are described by the researchers as having a "high radical-scavenging activity."

To verify the protective effects of strawberries and anthocyanins, Tulipani and her colleagues gave absolute ethanol to laboratory rats for a period of one hour, after which their stomachs were examined for injury in the form of ulceration.

Those rats that had been fed anthocyanin-containing strawberry extracts in the days leading up to ingestion of alcohol suffered significantly less gastric damage. What's more, the researchers found that rats that had consumed strawberry extract with a higher total anthocyanin content sustained significantly less gastric injury than those that had eaten less anthocyanin-rich extract.

The rats in the study were fed strawberry extract in quantities of 40 milligrams per day per kilogram of body weight, starting as much as 10 days before they were given alcohol. But according to Maurizio Batino, coordinator of the research group at the Marche Polytechnic University in Italy, "the consumption of strawberries during or after pathology could lessen stomach mucous membrane damage" as well.

So there you have it. Not that we'd ever be ones to condone heavy drinking, but remember: if you are planning on punishing your stomach lining this weekend, be sure to load up on strawberries in the days ahead. Just make sure to ask for the ones with extra anthocyanins.

The researchers' findings are published in the latest issue of PLoS ONE.

Drinking can wreak havoc on your insides, and not just the relatively short-lived brand of havoc brought on by a one-night drinking spree. We're talking long-term damage to the mucous membrane of your stomach that can give rise to all manner of gastrointestinal disorders, including ulcers, colorectal cancer, and inflammatory bowel disease.

Now a team of European scientists has found that strawberries can help mitigate the stomach-punishing effects of alcohol consumption, and could even help improve the treatment of stomach ulcers.

Sara Tulipani, researcher at the University of Barcelona and co-author of the study, explains that "the positive effects of strawberries are not only linked to their antioxidant capacity and high content of phenolic compounds, but also to the fact that they activate the antioxidant defenses and enzymes of the body."

Translation? Gastrointestinal diseases like stomach ulcers are caused in part by what are known as free radicals, which are atoms and molecules with unpaired electrons. The fact that these chemicals have unpaired electrons makes them unstable and highly reactive. In an attempt to regain stability, these free radicals will react with and try to nab electrons from other, normal molecules, giving rise to damaging chain reactions in your cells that accumulate over time.

Free radicals are the byproducts of oxidation reactions that go on inside your body; so when when Tulipani talks about the "antioxidant capacity" of strawberries, or their ability to activate the antioxidant defenses of the body, she's talking about their ability to inhibit the oxidation of other molecules, and, by extension, the production of harmful free radicals.

Finally, the phenolic compounds Tulipani is referring to are called anthocyanins (the same class of molecules that causes leaves to appear red during autumn), which are described by the researchers as having a "high radical-scavenging activity."

To verify the protective effects of strawberries and anthocyanins, Tulipani and her colleagues gave absolute ethanol to laboratory rats for a period of one hour, after which their stomachs were examined for injury in the form of ulceration.

Those rats that had been fed anthocyanin-containing strawberry extracts in the days leading up to ingestion of alcohol suffered significantly less gastric damage. What's more, the researchers found that rats that had consumed strawberry extract with a higher total anthocyanin content sustained significantly less gastric injury than those that had eaten less anthocyanin-rich extract.

The rats in the study were fed strawberry extract in quantities of 40 milligrams per day per kilogram of body weight, starting as much as 10 days before they were given alcohol. But according to Maurizio Batino, coordinator of the research group at the Marche Polytechnic University in Italy, "the consumption of strawberries during or after pathology could lessen stomach mucous membrane damage" as well.

So there you have it. Not that we'd ever be ones to condone heavy drinking, but remember: if you are planning on punishing your stomach lining this weekend, be sure to load up on strawberries in the days ahead. Just make sure to ask for the ones with extra anthocyanins.

The researchers' findings are published in the latest issue of PLoS ONE.

It seems like such a simple question, but it's actually one of the most biggest mysteries in all of science. Is it because of how our brains are organized, how ancient humans gripped tools, or is it simple anti-lefty prejudice?

Nobody knows for sure, but scientists have come up with theories that are alternately intriguing, persuasive, and a little bonkers. Let's take a look at the often baffling science of handedness, running from how the development of language in early humans might have helped cause the evolution of handedness...to how all the world's languages seem to have it in for lefties.

Why does handedness exist?

Handedness - the idea that one hand is better able to perform certain tasks than the other - is, if not exclusively a human trait, then certainly a mostly human one. After all, how could you tell if a dog was left-handed or a lion was right-handed? Their paws aren't evolved to handle complex tasks like our hands are, and there's no evidence that non-primates favor one limb over any other.

But exactly why humans favor different hands, or why most people tend to be right-handed, remains mysterious. The most common answer is that handedness is determined by the structure of our brains, which are divided into two hemispheres. Our brains are far more specialized than those of other animals, with different regions of the brain responsible for different specific tasks. Admittedly, these are only general guidelines, and most neural activities are shared between the hemispheres to some extent, but we can definitely say that many functions are primarily handled by one hemisphere as opposed to another. This is known as brain lateralization.

Two of the most energy-intensive human activities are language and the use of our fine motor skills - in other words, the use of our hands. One theory suggests that it's more efficient for the brain to cluster control of these two major tasks in one hemisphere rather than having it spread throughout the brain. Since the vast majority of people have their language functions centered in the left hemisphere, it follows that most people's fine motor skills would be controlled by the left hemisphere too. Each hemisphere generally controls the opposite side of the body, so the end result is that most people are right-handed.

However, the opposite does not hold true - being left-handed does not mean the language centers are located in the right hemisphere, which is fairly rare. Certainly, lefties are more likely than righties to have their right hemisphere responsible for language, but it's still not a common arrangement. Between 61 and 73% of lefties have their language centers in the left hemisphere, compared to over 90% of right-handed people.

This doesn't necessarily invalidate the division of labor theory. After all, between 70 and 90% of people are right-handed, and well over 90% of those people do indeed cluster language and fine motor skill control in the left hemisphere. What we're looking at here is the evolutionary equivalent of a rule of thumb. People's brains are generally organized to maximize energy efficiency, but a reasonably large minority of people - including most lefties - get along just fine with a less efficient arrangement.

But why are most people right-handed?

As we've discussed, another possible way of phrasing that is, "Why is the language center usually in the left hemisphere of the brain?" After all, if the energy intensive language centers happened to evolve so that they were usually in the right hemisphere, then most people would probably be left-handed instead. To that point, there's no reason why our brains couldn't have evolved that way - it's simply a historical fact that they didn't.

But that hasn't stopped scientists from attaching great significance to the fact that we evolved as righties instead of lefties. In the January 1, 2002 issue of Discover Magazine, Jocelyn Selim describes a particularly spectacular theory:

In most primates and other animals, the hemispheres of the brain divide the processing of tasks somewhat equally. But in humans, the hemispheres tend to specialize: Nearly all righties process language in the left side of the brain, while many lefties process language on the right. Because handedness and language both seemed uniquely human traits, biologists long assumed that they were closely linked.

One Oxford neurobiologist went so far as to argue that right-handedness could be traced back 200,000 years to a single mutation-a sort of genetic Big Bang that created hemispheric specialization, language, and higher cognitive functioning in one go. Right-handedness, to this way of thinking, is the most obvious mark of the genetic instructions that separate us from speechless, symmetric beasts.

While some of that that might be going a bit far - if nothing else, it doesn't seem to leave a lot of room for lefties - the root of handedness quite possibly is a random genetic mutation that pushed the language centers to the left hemisphere as the ancient human brain became more specialized. Without this particular genetic mutation, our brains still might have evolved to their present levels of sophistication, but our language hemispheres would be chosen at random, meaning handedness would be more evenly split.

In fact, a second major gene mutation might have had precisely that effect, at least in a subset of the population. University College London neuropsychologist Chris McManus suggests that sometime between 20,000 and 100,000 years ago, a second mutation entered the human gene pool that canceled out the brain's natural bias towards right-handedness, allowing for the emergence of more left-handers. People who carry this second mutation are also more likely to have unusual patterns of brain organization, which neatly explains why lefties are more to have both high intelligence and mental disorders.

So is it really all about language?

Well...that's just one theory. It's a pretty good one, as theories go, but it doesn't explain everything, and - as we've just seen - it very easily gets wrapped up in grand triumphal stories of humanity's brilliant evolution. Certainly, we should be careful in saying the development of language centers in the left hemisphere caused the rise of handedness. The two appear linked, but it may not be quite as direct as we might have imagined.

One issue is that we're not the only other animals to use a particular hemisphere of the brain to create noises. Birds and frogs, for instance, process the noises they make in one particular side of the brain, and there's no evidence of handedness in the way they use their limbs. University of Auckland researcher Michael Corballis suggests an alternative explanation for our handedness in the Discover article:

"It's quite possible that what set humans apart was that speech began from gestures, which would explain an indirect association with handedness. But it's one of those mysteries that refuses to resolve itself. Think of it this way: Primates do have very symmetrical brains, but then again, so did Einstein."

The division of labor theory and the two genetic mutations don't need to be thrown out - instead, we can roll them into a larger picture of the evolution of handedness. It's possible that the specialization of our brains were already pushing our species toward handedness, but this process was accelerated by the activities of ancient humans, in particular their use of tools. In a 2009 blog entry for Science, Michael Balter details one possible explanation for the rise of handedness:

The "technology-dense lifestyles" of early hominins might have required our ancestors to more or less make up their minds about what hands they were going to use to perform complex tasks. Moreover, such hand bias could have aided the learning process as hominins taught each other toolmaking and other skills; a number of studies have shown that people learn manually difficult tasks, such as knot-tying, more easily when they use the same left- and right-hand movements as their teachers.

We can also add into the mix the development of longstanding, pervasive social prejudices against left-handedness, which I'll discuss in more detail in a little bit. These prejudices likely influenced countless children who otherwise would have developed into lefties to essentially force themselves to be right-handed, effectively inflating the proportion of the right-handed population.

When did handedness first evolve?

We can feel reasonably confident that Neanderthals and Homo heidelbergensis were right-handed. Neanderthal skeletons tend to have stronger right arms and shoulders than their left counterparts, perhaps because they used them to throw spears while hunting animals. There's less direct evidence for Heidelbergensis, but we can tell from their preserved teeth indicate that they ate food with their right hands. The 1.6 million year old Homo ergaster skeleton Nariokotome Boy showed signs of right-handedness, but we can't infer the hand preference of an entire species from just one skeleton.

Determining the handedness of other primates is also tricky for a bunch of reasons. In general, wild primates aren't particularly likely to engage in the sorts of activities that require fine motor skills - and thus would require handedness - and it's hard to know whether we can really trust results we get from giving human-like tasks to captive primates. But as primatologist Bill Hopkins explains in the Discover article, decades of accumulated research have given us some rather unexpected answers:

A close look at primate research since the 1920s shows that all primates have hand preferences, and those preferences follow a clear pattern: Lemurs and other prosimians tend to be left-handed; macaques and other old-world monkeys are evenly split between lefties and righties; among gorillas and chimpanzees, 35 percent are lefties, while in humans that percentage hovers around 10. In other words, the more primitive the primate, the more likely it is to be a lefty. Left-handedness, far from being a recent invention, seems to predate right-handedness.

We know that the ancestor of all primates evolved about 65 to 85 million years ago as a member of the extinct order Plesiadapiformes. One of the last of the Plesiadapiformes was Carpolestes simpsoni, which had grasping digits like those of all its primate descendants. It's possible that the development of handedness goes right back to this very ancient transition from claws to digits.

Why primates apparently slowly moved from left-dominant to right-dominant as they evolved remains an open question. We could go back to the division of labor theory here. It's possible that because Carpolestes simpsoni and the earliest primates had small brains, they had to cluster control of their emerging motor skills in one hemisphere, which just happened to be the right.

This led to a lot of left-handed monkeys, but as larger, bigger-brained primates began to evolve, this division of labor became less important, which opened the door for a wider mix of righties and lefties. Of course, that doesn't explain why handedness started to swing towards righties as we get to chimps and gorillas is still - it's certainly possible that changing brain structure and random mutations played a major role, but we just don't know for sure.

What does it actually mean to be right-handed or left-handed?

After everything we've already discussed, that may seem likely a stupidly easy question, but it's surprisingly controversial. The everyday answer to that question is probably this: if you write with your right hand, then you're right-handed. It's a straightforward enough popular definition, but translating that into scientific terminology is trickier than you might think. Even simply saying that handedness is determined by which hand you prefer to use doesn't actually help us that much.

Let's consider some of the problems here. Should a person's dominant hand be determined by the hand they prefer to use, or the hand that performs better in tests? In other words, is handedness primarily psychological or physiological? Even if you can sort that out, there's still the question of how to categorize all this. Should left-handed and right-handed be considered precisely equal, or does the fact that such a vast majority of people are right-handed suggest that the people are simply either right or non-right? That's a bit of a charged way to look at things, but it does have some popularity in scientific literature.

And how about people who use different hands for different tasks? I write and throw with my right hand but bat and play(ed) hockey with my left hand - should I be considered primarily right-handed, a mix of right- and left-handed, or ambidextrous, meaning I feel equally comfortable using both hands? (Yeah...I'm probably not ambidextrous.) And should we look at handedness as something that can be lumped into only a very few categories - say true right-handed, more right-handed, ambidextrous/mix, more left-handed, and true left-handed - or something that exists on a broad spectrum?

Indeed, the very idea that one hand is "dominant" might be a complete misunderstanding of how our hands divide up tasks. In the Science post, Michael Balter details an argument by University of Liverpool archaeologist Natalie Uomini:

Uomini points out that handedness does not mean that one hand is "dominant" over the other. Rather, she writes, "both hands have different but equally important roles." In right-handed people, for example, the right hand might be used for tasks requiring greater manual dexterity whereas the left hand might perform the more mundane but nevertheless crucial role of supporting an object. (Imagine eating dinner with just a knife but no fork, for example.)

There isn't a ton of consensus here - ask a dozen scientists and you'll probably get at least ten different ways to define and organize handedness. Part of the problem here is that handedness is generally a pretty touchy issue, one with a long history of bias and prejudice. Speaking of which...

What exactly do people have against lefties?

For reasons that can probably best be described as "stupid", people have historically held left-handers in contempt. You can find evidence of an anti-left bias throughout the world's languages. The word "left" itself comes from the Anglo-Saxon word "lyft", which means "weak." We get the word "sinister" from the Latin word for "left", and that double meaning persists in the modern Romance languages.

It really is an insanely long list - English, French, Chinese, Korean, Finnish, Irish, Hungarian, Dutch, Spanish, Italian, Portuguese, German, and most of the Slavic languages all either link the word "right" with goodness, the word "left" with wrongness and impropriety, or both. That's not even getting into all the expressions and customs that have sprung up against left-handed people. In Ghana, even gesturing with the left hand can be considered taboo, and a common form of 19th century bigotry was to say minority groups such as homosexuals and Roman Catholics were left-handed.

As to why these prejudices exist - well, it does appear that majority right-handedness has been around at least since modern humans first emerged 200,000 years ago. This may simply be a case of a natural majority picking on a minority, perhaps out of an embarrassingly human fear of what's different. There's also at least one possible vaguely practical reason for this animosity. As any lefty will be happy to tell you, tons of everyday objects that right-handed people take for granted are a pain in the ass to use if you're a lefty. There's spiral notebooks, can-openers, stick shifts...and that's just what I remember from the Simpsons episode on the subject.

It's possible that ancient tools were similarly designed with right-handed users in mind, and the natural difficulties a lefty would have with such implements could draw social scorn and, over time, build up negative associations towards lefties. That all sounds fairly fanciful, honestly - although a few languages do have words that mean both "left" and "clumsy", suggesting a linked meaning somewhere along the line. Ultimately, we're probably just looking at good old-fashioned fear of the unusual.

There's really no definitive evidence either way that righties are better than lefties or vice versa - they just happen to hold their pencils differently. And while there have been a bunch of attempts to tease out specific differences between the two groups - including a recent study that basically suggested left-handedness is a form of cognitive impairment - there's way too much conflicting data out there to say much for certain.

As Chris McManus observed in the Discover article, ""The real question is why everyone wants left-handers to be defective", and there's a great deal of truth to that observation both throughout history and right up to now. Anyway, if this whole exercise has taught us anything, it's that we're probably just a couple random genetic mutations away from left-handers snootily trying to figure out what's up with that 30% minority of righties.

Further Reading

Is being left-handed a form of cognitive impairment? by Alasdair Wilkins
The Biology of Handedness by Jocelyn Selim
The Origins of Handedness by Michael Balter
What does Handedness have to do with Brain Lateralization (and who cares?) by M.K. Holder
Wild chimpanzees show population-level handedness for tool use by Elizabeth V. Londsor and William D. Hopkins

Image Credits

Top image by M.C. Escher.
Cerebral lobes via Wikimedia.
Green frog by thatredhead4 on Flickr.
Carpolestes simpsoni by Sisyphos23 on Wikimedia.
Leftorium via Loonpond.

It seems like such a simple question, but it's actually one of the most biggest mysteries in all of science. Is it because of how our brains are organized, how ancient humans gripped tools, or is it simple anti-lefty prejudice?

Nobody knows for sure, but scientists have come up with theories that are alternately intriguing, persuasive, and a little bonkers. Let's take a look at the often baffling science of handedness, running from how the development of language in early humans might have helped cause the evolution of handedness...to how all the world's languages seem to have it in for lefties.

Why does handedness exist?

Handedness - the idea that one hand is better able to perform certain tasks than the other - is, if not exclusively a human trait, then certainly a mostly human one. After all, how could you tell if a dog was left-handed or a lion was right-handed? Their paws aren't evolved to handle complex tasks like our hands are, and there's no evidence that non-primates favor one limb over any other.

But exactly why humans favor different hands, or why most people tend to be right-handed, remains mysterious. The most common answer is that handedness is determined by the structure of our brains, which are divided into two hemispheres. Our brains are far more specialized than those of other animals, with different regions of the brain responsible for different specific tasks. Admittedly, these are only general guidelines, and most neural activities are shared between the hemispheres to some extent, but we can definitely say that many functions are primarily handled by one hemisphere as opposed to another. This is known as brain lateralization.

Two of the most energy-intensive human activities are language and the use of our fine motor skills - in other words, the use of our hands. One theory suggests that it's more efficient for the brain to cluster control of these two major tasks in one hemisphere rather than having it spread throughout the brain. Since the vast majority of people have their language functions centered in the left hemisphere, it follows that most people's fine motor skills would be controlled by the left hemisphere too. Each hemisphere generally controls the opposite side of the body, so the end result is that most people are right-handed.

However, the opposite does not hold true - being left-handed does not mean the language centers are located in the right hemisphere, which is fairly rare. Certainly, lefties are more likely than righties to have their right hemisphere responsible for language, but it's still not a common arrangement. Between 61 and 73% of lefties have their language centers in the left hemisphere, compared to over 90% of right-handed people.

This doesn't necessarily invalidate the division of labor theory. After all, between 70 and 90% of people are right-handed, and well over 90% of those people do indeed cluster language and fine motor skill control in the left hemisphere. What we're looking at here is the evolutionary equivalent of a rule of thumb. People's brains are generally organized to maximize energy efficiency, but a reasonably large minority of people - including most lefties - get along just fine with a less efficient arrangement.

But why are most people right-handed?

As we've discussed, another possible way of phrasing that is, "Why is the language center usually in the left hemisphere of the brain?" After all, if the energy intensive language centers happened to evolve so that they were usually in the right hemisphere, then most people would probably be left-handed instead. To that point, there's no reason why our brains couldn't have evolved that way - it's simply a historical fact that they didn't.

But that hasn't stopped scientists from attaching great significance to the fact that we evolved as righties instead of lefties. In the January 1, 2002 issue of Discover Magazine, Jocelyn Selim describes a particularly spectacular theory:

In most primates and other animals, the hemispheres of the brain divide the processing of tasks somewhat equally. But in humans, the hemispheres tend to specialize: Nearly all righties process language in the left side of the brain, while many lefties process language on the right. Because handedness and language both seemed uniquely human traits, biologists long assumed that they were closely linked.

One Oxford neurobiologist went so far as to argue that right-handedness could be traced back 200,000 years to a single mutation-a sort of genetic Big Bang that created hemispheric specialization, language, and higher cognitive functioning in one go. Right-handedness, to this way of thinking, is the most obvious mark of the genetic instructions that separate us from speechless, symmetric beasts.

While some of that that might be going a bit far - if nothing else, it doesn't seem to leave a lot of room for lefties - the root of handedness quite possibly is a random genetic mutation that pushed the language centers to the left hemisphere as the ancient human brain became more specialized. Without this particular genetic mutation, our brains still might have evolved to their present levels of sophistication, but our language hemispheres would be chosen at random, meaning handedness would be more evenly split.

In fact, a second major gene mutation might have had precisely that effect, at least in a subset of the population. University College London neuropsychologist Chris McManus suggests that sometime between 20,000 and 100,000 years ago, a second mutation entered the human gene pool that canceled out the brain's natural bias towards right-handedness, allowing for the emergence of more left-handers. People who carry this second mutation are also more likely to have unusual patterns of brain organization, which neatly explains why lefties are more to have both high intelligence and mental disorders.

So is it really all about language?

Well...that's just one theory. It's a pretty good one, as theories go, but it doesn't explain everything, and - as we've just seen - it very easily gets wrapped up in grand triumphal stories of humanity's brilliant evolution. Certainly, we should be careful in saying the development of language centers in the left hemisphere caused the rise of handedness. The two appear linked, but it may not be quite as direct as we might have imagined.

One issue is that we're not the only other animals to use a particular hemisphere of the brain to create noises. Birds and frogs, for instance, process the noises they make in one particular side of the brain, and there's no evidence of handedness in the way they use their limbs. University of Auckland researcher Michael Corballis suggests an alternative explanation for our handedness in the Discover article:

"It's quite possible that what set humans apart was that speech began from gestures, which would explain an indirect association with handedness. But it's one of those mysteries that refuses to resolve itself. Think of it this way: Primates do have very symmetrical brains, but then again, so did Einstein."

The division of labor theory and the two genetic mutations don't need to be thrown out - instead, we can roll them into a larger picture of the evolution of handedness. It's possible that the specialization of our brains were already pushing our species toward handedness, but this process was accelerated by the activities of ancient humans, in particular their use of tools. In a 2009 blog entry for Science, Michael Balter details one possible explanation for the rise of handedness:

The "technology-dense lifestyles" of early hominins might have required our ancestors to more or less make up their minds about what hands they were going to use to perform complex tasks. Moreover, such hand bias could have aided the learning process as hominins taught each other toolmaking and other skills; a number of studies have shown that people learn manually difficult tasks, such as knot-tying, more easily when they use the same left- and right-hand movements as their teachers.

We can also add into the mix the development of longstanding, pervasive social prejudices against left-handedness, which I'll discuss in more detail in a little bit. These prejudices likely influenced countless children who otherwise would have developed into lefties to essentially force themselves to be right-handed, effectively inflating the proportion of the right-handed population.

When did handedness first evolve?

We can feel reasonably confident that Neanderthals and Homo heidelbergensis were right-handed. Neanderthal skeletons tend to have stronger right arms and shoulders than their left counterparts, perhaps because they used them to throw spears while hunting animals. There's less direct evidence for Heidelbergensis, but we can tell from their preserved teeth indicate that they ate food with their right hands. The 1.6 million year old Homo ergaster skeleton Nariokotome Boy showed signs of right-handedness, but we can't infer the hand preference of an entire species from just one skeleton.

Determining the handedness of other primates is also tricky for a bunch of reasons. In general, wild primates aren't particularly likely to engage in the sorts of activities that require fine motor skills - and thus would require handedness - and it's hard to know whether we can really trust results we get from giving human-like tasks to captive primates. But as primatologist Bill Hopkins explains in the Discover article, decades of accumulated research have given us some rather unexpected answers:

A close look at primate research since the 1920s shows that all primates have hand preferences, and those preferences follow a clear pattern: Lemurs and other prosimians tend to be left-handed; macaques and other old-world monkeys are evenly split between lefties and righties; among gorillas and chimpanzees, 35 percent are lefties, while in humans that percentage hovers around 10. In other words, the more primitive the primate, the more likely it is to be a lefty. Left-handedness, far from being a recent invention, seems to predate right-handedness.

We know that the ancestor of all primates evolved about 65 to 85 million years ago as a member of the extinct order Plesiadapiformes. One of the last of the Plesiadapiformes was Carpolestes simpsoni, which had grasping digits like those of all its primate descendants. It's possible that the development of handedness goes right back to this very ancient transition from claws to digits.

Why primates apparently slowly moved from left-dominant to right-dominant as they evolved remains an open question. We could go back to the division of labor theory here. It's possible that because Carpolestes simpsoni and the earliest primates had small brains, they had to cluster control of their emerging motor skills in one hemisphere, which just happened to be the right.

This led to a lot of left-handed monkeys, but as larger, bigger-brained primates began to evolve, this division of labor became less important, which opened the door for a wider mix of righties and lefties. Of course, that doesn't explain why handedness started to swing towards righties as we get to chimps and gorillas is still - it's certainly possible that changing brain structure and random mutations played a major role, but we just don't know for sure.

What does it actually mean to be right-handed or left-handed?

After everything we've already discussed, that may seem likely a stupidly easy question, but it's surprisingly controversial. The everyday answer to that question is probably this: if you write with your right hand, then you're right-handed. It's a straightforward enough popular definition, but translating that into scientific terminology is trickier than you might think. Even simply saying that handedness is determined by which hand you prefer to use doesn't actually help us that much.

Let's consider some of the problems here. Should a person's dominant hand be determined by the hand they prefer to use, or the hand that performs better in tests? In other words, is handedness primarily psychological or physiological? Even if you can sort that out, there's still the question of how to categorize all this. Should left-handed and right-handed be considered precisely equal, or does the fact that such a vast majority of people are right-handed suggest that the people are simply either right or non-right? That's a bit of a charged way to look at things, but it does have some popularity in scientific literature.

And how about people who use different hands for different tasks? I write and throw with my right hand but bat and play(ed) hockey with my left hand - should I be considered primarily right-handed, a mix of right- and left-handed, or ambidextrous, meaning I feel equally comfortable using both hands? (Yeah...I'm probably not ambidextrous.) And should we look at handedness as something that can be lumped into only a very few categories - say true right-handed, more right-handed, ambidextrous/mix, more left-handed, and true left-handed - or something that exists on a broad spectrum?

Indeed, the very idea that one hand is "dominant" might be a complete misunderstanding of how our hands divide up tasks. In the Science post, Michael Balter details an argument by University of Liverpool archaeologist Natalie Uomini:

Uomini points out that handedness does not mean that one hand is "dominant" over the other. Rather, she writes, "both hands have different but equally important roles." In right-handed people, for example, the right hand might be used for tasks requiring greater manual dexterity whereas the left hand might perform the more mundane but nevertheless crucial role of supporting an object. (Imagine eating dinner with just a knife but no fork, for example.)

There isn't a ton of consensus here - ask a dozen scientists and you'll probably get at least ten different ways to define and organize handedness. Part of the problem here is that handedness is generally a pretty touchy issue, one with a long history of bias and prejudice. Speaking of which...

What exactly do people have against lefties?

For reasons that can probably best be described as "stupid", people have historically held left-handers in contempt. You can find evidence of an anti-left bias throughout the world's languages. The word "left" itself comes from the Anglo-Saxon word "lyft", which means "weak." We get the word "sinister" from the Latin word for "left", and that double meaning persists in the modern Romance languages.

It really is an insanely long list - English, French, Chinese, Korean, Finnish, Irish, Hungarian, Dutch, Spanish, Italian, Portuguese, German, and most of the Slavic languages all either link the word "right" with goodness, the word "left" with wrongness and impropriety, or both. That's not even getting into all the expressions and customs that have sprung up against left-handed people. In Ghana, even gesturing with the left hand can be considered taboo, and a common form of 19th century bigotry was to say minority groups such as homosexuals and Roman Catholics were left-handed.

As to why these prejudices exist - well, it does appear that majority right-handedness has been around at least since modern humans first emerged 200,000 years ago. This may simply be a case of a natural majority picking on a minority, perhaps out of an embarrassingly human fear of what's different. There's also at least one possible vaguely practical reason for this animosity. As any lefty will be happy to tell you, tons of everyday objects that right-handed people take for granted are a pain in the ass to use if you're a lefty. There's spiral notebooks, can-openers, stick shifts...and that's just what I remember from the Simpsons episode on the subject.

It's possible that ancient tools were similarly designed with right-handed users in mind, and the natural difficulties a lefty would have with such implements could draw social scorn and, over time, build up negative associations towards lefties. That all sounds fairly fanciful, honestly - although a few languages do have words that mean both "left" and "clumsy", suggesting a linked meaning somewhere along the line. Ultimately, we're probably just looking at good old-fashioned fear of the unusual.

There's really no definitive evidence either way that righties are better than lefties or vice versa - they just happen to hold their pencils differently. And while there have been a bunch of attempts to tease out specific differences between the two groups - including a recent study that basically suggested left-handedness is a form of cognitive impairment - there's way too much conflicting data out there to say much for certain.

As Chris McManus observed in the Discover article, ""The real question is why everyone wants left-handers to be defective", and there's a great deal of truth to that observation both throughout history and right up to now. Anyway, if this whole exercise has taught us anything, it's that we're probably just a couple random genetic mutations away from left-handers snootily trying to figure out what's up with that 30% minority of righties.

Further Reading

Is being left-handed a form of cognitive impairment? by Alasdair Wilkins
The Biology of Handedness by Jocelyn Selim
The Origins of Handedness by Michael Balter
What does Handedness have to do with Brain Lateralization (and who cares?) by M.K. Holder
Wild chimpanzees show population-level handedness for tool use by Elizabeth V. Londsor and William D. Hopkins

Image Credits

Top image by M.C. Escher.
Cerebral lobes via Wikimedia.
Green frog by thatredhead4 on Flickr.
Carpolestes simpsoni by Sisyphos23 on Wikimedia.
Leftorium via Loonpond.

Beneath the biases of intuition, or how your experiencing self and your remembering self shape your life.

Legendary Israeli-American psychologist Daniel Kahneman is one of the most influential thinkers of our time. A Nobel laureate and founding father of modern behavioral economics, his work has shaped how we think about human error, risk, judgement, decision-making, happiness, and more. For the past half-century, he has profoundly impacted the academy and the C-suite, but it wasn’t until this month’s highly anticipated release of his “intellectual memoir,” Thinking, Fast and Slow, that Kahneman’s extraordinary contribution to humanity’s cerebral growth reached the mainstream — in the best way possible.

Absorbingly articulate and infinitely intelligent, this “intellectual memoir” introduces what Kahneman calls the machinery of the mind — the dual processor of the brain, divided into two distinct systems that dictate how we think and make decisions. One is fast, intuitive, reactive, and emotional. (If you’ve read Jonathan Haidt’s excellent The Happiness Hypothesis, as you should have, this system maps roughly to the metaphor of the elephant.) The other is slow, deliberate, methodical, and rational. (That’s Haidt’s rider.)

The mind functions thanks to a delicate, intricate, sometimes difficult osmotic balance between the two systems, a push and pull responsible for both our most remarkable capabilities and our enduring flaws. From the role of optimism in entrepreneurship to the heuristics of happiness to our propensity for error, Kahneman covers an extraordinary scope of cognitive phenomena to reveal a complex and fallible yet, somehow comfortingly so, understandable machine we call consciousness.

Much of the discussion in this book is about biases of intuition. However, the focus on error does not denigrate human intelligence, any more than the attention to diseases in medical texts denies good health… [My aim is to] improve the ability to identify and understand errors of judgment and choice, in others and eventually in ourselves, by providing a richer and more precise language to discuss them.” ~ Daniel Kahneman

Among the book’s most fascinating facets are the notions of the experiencing self and the remembering self, underpinning the fundamental duality of the human condition — one voiceless and immersed in the moment, the other occupied with keeping score and learning from experience. Kahneman spoke of these two selves and the cognitive traps around them in his fantastic 2010 TED talk:

The word happiness is just not a useful word anymore because we apply it to too many different things.”

What’s most enjoyable and compelling about Thinking, Fast and Slow is that it’s so utterly, refreshingly anti-Gladwellian. There is nothing pop about Kahneman’s psychology, no formulaic story arc, no beating you over the head with an artificial, buzzword-encrusted Big Idea. It’s just the wisdom that comes from five decades of honest, rigorous scientific work, delivered humbly yet brilliantly, in a way that will forever change the way you think about thinking.

Thanks, Sean

Brain Pickings has a free weekly newsletter and people say it’s cool. It comes out on Sundays and offers the week’s best articles. Here’s an example. Like? Sign up.

Brain Pickings takes 450+ hours a month to curate and edit across the different platforms, and keeping it ad-free isn't easy. If it brings you any joy and inspiration, please consider a modest donation – it lets me know I'm doing something right.

Beneath the biases of intuition, or how your experiencing self and your remembering self shape your life.

Legendary Israeli-American psychologist Daniel Kahneman is one of the most influential thinkers of our time. A Nobel laureate and founding father of modern behavioral economics, his work has shaped how we think about human error, risk, judgement, decision-making, happiness, and more. For the past half-century, he has profoundly impacted the academy and the C-suite, but it wasn’t until this month’s highly anticipated release of his “intellectual memoir,” Thinking, Fast and Slow, that Kahneman’s extraordinary contribution to humanity’s cerebral growth reached the mainstream — in the best way possible.

Absorbingly articulate and infinitely intelligent, this “intellectual memoir” introduces what Kahneman calls the machinery of the mind — the dual processor of the brain, divided into two distinct systems that dictate how we think and make decisions. One is fast, intuitive, reactive, and emotional. (If you’ve read Jonathan Haidt’s excellent The Happiness Hypothesis, as you should have, this system maps roughly to the metaphor of the elephant.) The other is slow, deliberate, methodical, and rational. (That’s Haidt’s rider.)

The mind functions thanks to a delicate, intricate, sometimes difficult osmotic balance between the two systems, a push and pull responsible for both our most remarkable capabilities and our enduring flaws. From the role of optimism in entrepreneurship to the heuristics of happiness to our propensity for error, Kahneman covers an extraordinary scope of cognitive phenomena to reveal a complex and fallible yet, somehow comfortingly so, understandable machine we call consciousness.

Much of the discussion in this book is about biases of intuition. However, the focus on error does not denigrate human intelligence, any more than the attention to diseases in medical texts denies good health… [My aim is to] improve the ability to identify and understand errors of judgment and choice, in others and eventually in ourselves, by providing a richer and more precise language to discuss them.” ~ Daniel Kahneman

Among the book’s most fascinating facets are the notions of the experiencing self and the remembering self, underpinning the fundamental duality of the human condition — one voiceless and immersed in the moment, the other occupied with keeping score and learning from experience. Kahneman spoke of these two selves and the cognitive traps around them in his fantastic 2010 TED talk:

The word happiness is just not a useful word anymore because we apply it to too many different things.”

What’s most enjoyable and compelling about Thinking, Fast and Slow is that it’s so utterly, refreshingly anti-Gladwellian. There is nothing pop about Kahneman’s psychology, no formulaic story arc, no beating you over the head with an artificial, buzzword-encrusted Big Idea. It’s just the wisdom that comes from five decades of honest, rigorous scientific work, delivered humbly yet brilliantly, in a way that will forever change the way you think about thinking.

Thanks, Sean

Brain Pickings has a free weekly newsletter and people say it’s cool. It comes out on Sundays and offers the week’s best articles. Here’s an example. Like? Sign up.

Brain Pickings takes 450+ hours a month to curate and edit across the different platforms, and keeping it ad-free isn't easy. If it brings you any joy and inspiration, please consider a modest donation – it lets me know I'm doing something right.

Even in decidedly "wealthy" countries, human health is not always guaranteed. In fact, studies show that the best indicator of a country's health is not its overall wealth, but how that wealth is distributed. Time Magazine's Maia Szalavitz reports:

Imagine there was one changeable factor that affected virtually every measure of a country's health- including life expectancy, crime rates, addiction, obesity, infant mortality, stroke, academic achievement, happiness and even overall prosperity. Indeed, this factor actually exists.

It's called economic inequality. A growing body of research suggests that such inequality - more so than income or absolute wealth alone — has a profound influence on a population's health, in every socioeconomic group from rich to middle class to poor.

Economic inequality is measured by looking at the distribution of wealth and income in a society, not the general wealth of a country. At a basic level, a country's overall economic success does predict its people's well-being, but the healthiest and happiest countries in the world are not the richest. Rather, they are countries where wealth is shared widely and more equally.

One of the most obvious ways that economic equality may improve a country's overall health is by improving access to health care for all of its citizens, but Szalavitz writes that poor overall health manages to persist, "even in countries with national health services." So from where, exactly, does the negative correlation between economic inequality and public health stem?

"The roots of the problem," write Szalavitz,"appear to reach deeper than [access to public health care]. Indeed, they may go back to the dominance hierarchies of our primate ancestors."

Read the rest of Szalavitz's excellent piece over at TIME.
Top image via

The network of global corporate control (PDF), a study published in PLOS One, analyzes the ownership structures of the world's corporations and finds a tightly-knit cluster of 147 entities control 40 percent of the world's wealth. Not only is this creepy inasmuch as it puts a lot of power into a small number of hands, but it also suggests that the governance of much of the world's wealth is closely correlated, so one disaster could sweep like wildfire across them all:

The work, to be published in PloS One, revealed a core of 1318 companies with interlocking ownerships (see image). Each of the 1318 had ties to two or more other companies, and on average they were connected to 20. What's more, although they represented 20 per cent of global operating revenues, the 1318 appeared to collectively own through their shares the majority of the world's large blue chip and manufacturing firms - the "real" economy - representing a further 60 per cent of global revenues.

When the team further untangled the web of ownership, it found much of it tracked back to a "super-entity" of 147 even more tightly knit companies - all of their ownership was held by other members of the super-entity - that controlled 40 per cent of the total wealth in the network. "In effect, less than 1 per cent of the companies were able to control 40 per cent of the entire network," says Glattfelder. Most were financial institutions. The top 20 included Barclays Bank, JPMorgan Chase & Co, and The Goldman Sachs Group.

(via Kottke)

Revealed – the capitalist network that runs the world [newscientist.com]

Despite numerous studies indicating that cell phones pose no health risk to their users, a few studies have been released that suggest prolonged use might contribute to brain cancer. For the World Health Organization, that was enough to declare the phones "possibly carcinogenic" and to call for further studies on the link.

At least one of these studies was already in the works. Some specific features of how Denmark tracks its citizens have made that nation a convenient laboratory for long-term population studies. Now, one study has looked at almost the entire Danish adult population and found that having a cell phone doesn't seem to be associated with any additional risk of brain cancers.

Read the comments on this post

I'm not sure I have any comment for this, other than to say how pleased I am that puns work just as well in math.