Giving is reduced in diverse societies

In all populations individuals must struggle to balance their personal interest with sacrificing for the greater good of the whole.  Viewed in terms of the Darwinian struggle for survival of the fittest, there is an evolutionary advantage to sacrificing selflessly (altruism), if that personal sacrifice provides one’s genetically-related group an advantage.  Think bees that lose their life when they sting a predator so that the hive can survive and pass on genes that are related to the defender.  In other words, individuals sacrifice because there is a reward to their genetic heritage in doing so.  By this reasoning, ethnic and religious diversity in a society should undermine cooperation, but does it?  And if diversity does undermine cooperation and altruism, is there some way societies can overcome the animal instinct to flock with one’s own kind.  These are especially acute questions as barriers to travel fall, promoting diversity in countries around the globe, and as ethnically and religiously different groups of people clash around the world.

            A study by political scientists Fotini Christia, at MIT and Marcus Alexander at Stanford University published in the December 9, 2011 issue of the journal Science exploited a unique situation in Bosnia-Herzegovina to find answers to these questions.  The court ordered integration across ethnic lines separating Christians and Muslims in two of the four high schools in Mostar, Bosnia-Herzegovina, allowing researchers to study of the effects of ethnic diversity and forced integration on altruism.  Since the integration was compulsory in the two integrated schools, the results were not biased by issues of self selection. 

            In these studies, students participated in a computer-based public-good game, in which each player in a group of four contributed money to the public treasury.  After everyone contributes, the pot is divided up and distributed equally among all players regardless of how much each player contributed.  In one scenario, free-loaders who contribute nothing will have the greatest individual success.  In contrast to that stingy approach, if everyone generously gave away all of their money, this would provide the maximum benefit to the group as a whole once the pot was split equally. 

So to make the situation more interesting, by encouraging individuals to act in a self-less manner for the maximum benefit to the group, sanctions were imposed on those who contributed the least.  The amount of sanctions to be imposed was determined after players were informed of the level of contribution made by the other players.  Since other players will soon learn how much an individual contributes, each player is in a way communicating to others how much of their wealth they feel should be provided for public good.  A “stingy” group of players might settle on an average of say a 10% contribution of their individual funds to the pot, and a “generous” group of players might settle on a donation of 30%.  Thus, researchers have a numerical measure of how altruistic different groups of players are.

What the researchers found was that when groups of players were from diverse backgrounds, that is, a mixture of Christians and Muslims, the individuals contributed less to the pot.  Diversity decreases altruism.  The negative effect of diversity was quite large, cutting contributions to 1/3 of the amount contributed when the individuals were playing in groups that were composed of ethnically homogenous members (Christians with Christians and Muslims with Muslims).  This outcome fits perfectly with Darwinian thinking.

Now, what if the players had come from an integrated or a segregated school?  The researchers found that if the players had come from integrated high schools, contributions were not much different when they played in mixed or segregated groups. 

Sanctions had a very different effect on contributions, depending on whether the players came from integrated or segregated schools.  If students had come from integrated schools, costly sanctions had a large effect in increasing altruism regardless of whether they played in homogenous or mixed groups, but when subjects were from segregated schools, sanctions had no effect on contribution to public good, regardless of whether they played in homogenous or racially mixed groups.  Sanctions, the authors suggest, don’t seem to work in a homogenous society because there is a high sense of intra-group kinship that reduces the threat of sanctioning. 

If these results can be extrapolated beyond this uniquely war-torn society, it can be concluded that diversity reduces individual contributions to the public good, but only when individuals come from segregated schools.  In contrast, when individuals come from integrated institutions, the difference in contributions to public good in homogenous and racially/religiously mixed groups is eliminated.  Thus, human beings have within their power the ability to modify the animal-based instinct that undermines cooperation among diverse populations by implementing social measures, and this should promote better-ordered and more cooperative societies. 

Can Science Explain the Marked Increase in Shark Attacks?

  Authorities in Western Australia have failed in their attempt to hunt down and kill a great white shark that took the life of a 32 year old American diver, George Wainwright last  Saturday.  This is the fourth fatal attack by sharks in Australia in the last 14 months—three times the annual average.  There have been 13 shark attack deaths world-wide this year, and statistics show that the number of shark attacks have increased steadily for decades. 

I studied sharks for my MA and PhD degree in Biological Oceanography; I’ve been diving with them, and I’ve seen them explode into a feeding frenzy attacking their normal prey.  So after this recent attack I contacted some of the world’s leading authorities on sharks and shark attack to get their expert opiniosn.

John West, of the Taronga Zoo, in Australia and Curator of the Australian Shark Attack File, indicated in an e-mail for this article that shark attack numbers in Australia have increased steadily over the last 20 years.  “We are talking about an average of 4.6 cases per year in the 1970’s, 6.4 in the 1980’s, 8.2 in the 1990’s, and 16.1 cases per year in the 2000’s.”

George Burgess, shark researcher and curator of the International Shark Attack File at the Florida Museum of Natural History, confirms a similar trend from his data.    “If one looks at the last eleven decades from 1900 through 2010, what one finds is that there is an increase in the number of attacks each decade, without fail, which would suggest to the casual viewer, that we’re under siege,” he says.  Both experts agree that there a scientific explanation for these alarming data and the spike in recent fatal shark attacks. 

The steady increase in shark attacks is easily explained by the increase in human population and growing popularity of water related sports and recreational activities.  “The increase in shark attacks is largely a function of human demographics and growth.  The number we get in any given year is purely a function of how many people went into the water,” says Burgess. 

There are, however, some new patterns emerging from Burgess’ data on shark attacks.  “There has been an increase this year [in shark attacks] in a number of areas where we have not traditionally had such attacks, undoubtedly by white sharks, most notably the three series of attacks in Russia in areas of cold water most of the time,” he says.  This, he explains is due to warming of waters, possibly associated with global warming, that are allowing sharks to expand their range farther north and south into waters that they normally do not go, and also because warmer water induces more people entering the sea.    

Contrary to the sensational scenes in the movie Jaws portraying maniacal sharks stalking and terrorizing bathers, most attacks on humans are mistakes.  “We all need to remember that we are not a natural part of the marine environment,” Burgess observes.  “So therefore we are not likely to be a preferred food item of any animal in the sea, simply because we are foreign objects every time we are encountered.  In fact, most commonly sharks will move away from us as we represent an unknown entity and the natural reaction is to show caution.”

“Here in Florida where we have more shark bites than anywhere else in the world.  These interactions are almost surely mistaken identity, because the animals involved are small—six feet or less in size—and species of sharks that are typically shrimp eaters that don’t normally go after large prey items.  Their teeth are not designed evolutionarily for tearing, but rather for grabbing and swallowing whole.”  When these sharks feed in the murky surf zone where the jostling of waves and currents forces them to rely on quick grabs to feed, a flailing leg or arm of a bather frolicking in the surf can be mistaken for the animal’s normal prey.

There are exceptions, however.  “Other animals like white sharks, tiger sharks, bull sharks, of large size whose teeth are designed for shearing and who normally go after large prey item can in some cases see humans as simply representing an appropriate sized and perhaps appropriately behaviored image of the normal prey item.”  The silhouette of surfer in a black wetsuit paddling on the surface can resemble a seal, for example.  “You can’t dismiss all bull shark and white shark attacks on humans as cases of mistaken identity; a human simply looks like something worthy of a trial.” 

What can be done to prevent such predatory attacks on humans?  Some, as has happened after the recent fatal attack in Australia, argue for “culling” the shark population and hunting down and killing the suspected killer shark.  This, Burgess argues, is futile. 

“Obviously trying to kill the killer is just really a waste of time and public resources, simply because you can’t identify the individual shark in any other way than to kill the shark and open the stomach and hope to find a piece of human in it.  That’s a shot in the dark.  The chances of finding a killer are pretty much slim to none.”

The difficulty of identifying the killer, which popular folk lore would have terrorizing a local coastal community, is compounded by the biology of large sharks.  “White sharks are highly mobile and they move 40 to 50 miles a day.  So the chances of the killer shark being caught after an attack are pretty much nil, because that animal has probably long gone.” 

 Moreover, this eye-for-an-eye approach to shark attacks can have devastating ecological effects.  The studies of Gregor Cailliet, Professor Emeritus, Moss Landing Marine Laboratories and Program Director for the Pacific Shark Research Center, have highlighted the vulnerability of sharks to predation by humans, because unlike many fish, sharks take a long time to reach sexual maturity and most species only have a small number of offspring.  “In my opinion Jaws (the movie) and Shark Week, etc., are not good things, but rather sensationalize the situation,” he says.

Moreover, the number of shark species that are dangerous is exceedingly small.  “Remember there are almost 1,200 species of sharks, rays and chimaeras worldwide and the white, bull and tiger sharks [most often implicated in attacks on humans] are only three of these,” observes Cailliet. 

The experts advise that understanding and respecting the biology and ecology of sharks can enable one to avoid becoming shark bait.

“People need to use common sense in deciding where and when to be in the water and doing what.  For example, areas where pinnipeds [seals and sea lions] have pupping grounds, and often costal points outside of kelp beds, are “hot spots” off California, says Professor Cailliet. 

The most recent fatal attack on the diver in Australia took place in an area where white sharks would have been expected to be feeding.  “The place where he was [attacked] was close to a seal colony.  We see a number of shark attacks on humans around seal colonies,” Burgess says. 

Moreover the location of the attack is in the migratory route for whales.  “Whales move through this area at this time of year, every year, and where there are migratory whales there are white sharks following.  We see this right along our coast–the East Coast–in the winter as the Right Whales head south off of Georgia and Florida, white sharks follow them as well.  The only time we see white sharks in Florida is in the winter time when they follow the whales down.” 

It also appears from initial reports that this diver was engaged in spear fishing.  If so, this attack would be classified in the shark attack files as a “provoked attack” because the blood and frantic movements of speared fish would attract sharks to the area and provoke them to feed. 

“Sharks have more to fear from humans than humans have from sharks,” observes John McCosker, an expert on white sharks at the California Academy of Sciences in California.  He advises people to avoid areas where there is a history of attacks, and that the new thrill-seeking “shark dives” being offered adventurous divers runs counter to common sense.  “I suspect that this is contributing to an unrealistic perception of the risks associated with such stupidity; however, surprising, I’m not aware of a significant increase in attacks [in such dives].  The risk of diving with white sharks in the Northeast Pacific, as is done in California and Guadalupe Island, Mexico, will increase if people think that it is safe to leave the protection of a cage.” 

One needs to keep the risk of shark attack in perspective.   These are very rare events.  “Over the past 50 years there is an average of around one person killed by a shark each year in Australia, yet there is also an average of 87 people that drown every year at our beaches [in Australia], says John West. 

All of the shark authorities consulted for this article agree that the general population has a distorted and sensationalized view of sharks.  “I think the only words most people hear or read and retain are ‘dangerous’ and ‘predator’ even when an article or documentary is balanced,” West says.  “Of all the people I have spoken to over my 40 years involved with sharks, 99.5%  have never seen a live wild shark yet 99% are fearful of sharks—where do they get this fear from?  I think it is the media and associated movies.” 

People seem to have forgotten the basic biological facts with respect to humans and sharks.  “When we enter the sea, we need to understand that we are visiting a foreign environment,” Burgess observes.  “We are terrestrial animals.  Our evolution occurred on land.  We don’t have gills.  We can’t swim very well, and as such every time we enter the sea it is a wilderness experience for us.  One of the mistaken impressions that we as humans have is that we are owed the right to be safe 100 percent of the time wherever we go in the world.  That’s a pretty haughty view that humans have– that we should be able to control every phase of the world we live in.  In the sea we should accept a certain amount of risk, and it is incumbent upon us to reduce the chances of risk by being smart.  But any way you look at it, when you enter the sea it is a wilderness experience.”

 Further Reading:

Fields, R. Douglas (2007)  The Shark’s Electric Sense.  Scientific American, August, p. 75-81. 

http://www.scientificamerican.com/article.cfm?id=the-sharks-electric-sense

 

What would President Kennedy have thought, I wondered as I surveyed the surreal scene?  Deep inside the White House eight middle school students sat in black leather executive chairs reserved for the President, Vice President, and his top national security advisors; the polished oak boardroom table hitting them at chest level as they munched hotdogs and hamburgers.  This room is where the nation’s most critical decisions in times of national crisis had been made by every president from Kennedy to Obama. 

The students, 12-14 years old, were in town to participate in the American Association for the Advancement of Science Annual Meeting in Washington, D.C.  Working collaboratively with scientists in their home state of Minnesota and students, their teacher and scientists in the D.C. area, the children had come to share their experimental results and rub elbows with real scientists attending the annual meeting from around the world.  Tours of the White House and Smithsonian were an added highlight, but to everyone’s surprise, the group of young scientists had their standard White House tour extended as they were ushered through layers of additional security to find themselves unexpectedly in this room. 

With anxious excitement the students answered questions about their science projects posed by a top national security official seated at the head of the table where moments before he had chaired a meeting of the nation’s leaders in national security as they assessed the explosive revolutions transforming the Middle East.  On the other side of the globe democratic protestors were being shot and autocratic rulers were being toppled from power after decades of iron fisted rule as our national security officials monitored the rapidly changing situation on a cold and windy Saturday afternoon in Washington. 

The official then explained the strategic repercussions of the revolution now unfolding in Bahrain because of that nation’s pivotal geographic position in the Gulf region and its delicate balance point in the political tensions between Sunni and Shiite Muslims.   Then pointing to the presidential seal on the wall behind him he explained that the American eagle faces in the direction of the olive branch grasped in its talons during times of peace, but in times of war the eagle turned toward its talons grasping arrows.  The most powerful defense our nation has is not its weapons, he said.  President Obama believes it is our superiority in science and technology, and the strength of the American people.  He spoke with great respect of a four star general in the Marines and leader of national security who was not only a patriot, but also a physicist.  He recognized and honored the children as individuals who would be the scientists of America’s future. 

Later that day as we toured the National Air and Space Museum I rattled off descriptions of the displays as if the objects were my own personal treasures.  The sleek black X-15, dropped from the belly of a plane and jolted by rocket engines at speeds of over Mach 6 to pierce the edge of outer space; the Mercury, Gemini, and Apollo space capsules and Lunar Landing Module; an exhibit placing the viewer inside the cockpit of Apollo 11 as a video displays the scene that Neil Armstrong watched through the portholes of his spacecraft as he crisply narrates his descent and touch-down on the surface of the moon.  I knew the script by heart, having lived all these events as a child.

There is no doubt that President Kennedy’s vision to promote scientific research in the challenging adventure of the space program had a powerful impact on me becoming a scientist.  I noticed too that my scientific colleague from Minnesota and my wife, a biology teacher whose students were participating in the AAAS meeting, knew all the stories behind each exhibit.  President Kennedy saw advancing science as the most critical aspect of national security.  Now history was unfolding to the wisdom of Kennedy’s vision.  It was not missiles bringing down Middle East Tyrants, it was the internet.  Developed from the primitive electronic circuits inside the guidance systems of rockets, electronic computers are now in the hands of people around the globe, and guiding them to a better future.

For the first time, though, all the space technology on display that once sparked the superlative “space age” adjective applied to the most advanced technologies looked archaic.  These objects had truly become museum pieces.  Countries like China, India, Iran, the national security advisor told us, are pouring great effort into science education, and students in many countries now outpace students in the United States in math and science. 

We all heard this message from the President in his recent State of the Union Address, but I wonder if science education, like “mom and apple pie” is just filler to buoy a politician’s speech.  The room fell silent as the official was handed a document from an aide.  Looking up he told the kids that the President had just returned from California and Oregon where he had met with CEOs of high-tech companies.  With apologies he explained that he needed to meet with the President in ten minutes and that an aide would see us out after we finished lunch.

Overwhelmed with excitement the students devoured their meal and questioned the aide, a Marine, about his experiences in the White House.  The familiar knot in the stomach of any parent who has taken their children to a fancy restaurant began to churn.  The table was becoming strewn with crumbs and poppy seeds from the hamburger buns.  My eyes searched the glossy table top and leather seats for greasy fingerprints.  Periodic “shushes” lowered the volume of the excited conversations, but their effect was temporary. 

Suddenly the door burst open and a tall athletic secret service agent burst in.  “What’s going on in here!” he demanded. The children screamed.  A thirteen year-old boy, who could have resembled the preadolescent president, sprung from his seat and tackled the man around the waist screaming with joy.  Not a secret service agent, it was the President of the United States!  The seats emptied as the children surrounded him in a middle-school group hug.  “Where are the teachers, he asked?”  He met each one and thanked every one personally with a handshake.  He told the kids how important science was to the nation and congratulated them all on their work. 

We were all stunned.  This was not a photo op.  The meeting was not scheduled.  The President of the United States had just stepped off the helicopter and on the way to an important meeting with staff to discuss national security, he made the decision to visit and congratulate the young scientists.

Photographs are not generally permitted inside the White House, but the President made an exception.  All he asked was that we keep it for our personal treasure and not post it on the internet or make it public.  I wish you could see the beaming faces of the kids and teachers surrounding the president, the one boy still latched to the President’s waist like a child hugging his father returning from a trip.  Standing beneath the Presidential seal, President Obama looks so perfect it might have been a picture contrived using one of those Obama cut-out props tourists use to place themselves in a photo with the President.  It all seems like a dream, which indeed it was.  But the kind of dream that is true.

Blind people in the study could hear speech as fast as 25 syllables a second!

21sps

14sps

24sps

For those of us who are sighted, here is a transcript of the sound clips:

“Blackwater, now called Xe Services, was once the United States’ go-to contractor in Iraq and Afghanistan. It has been under intense pressure since 2007, when Blackwater guards were accused of killing 17 civilians in Nisour Square in Baghdad. The company, its executives and personnel have faced civil lawsuits, criminal charges and congressional investigations surrounding accusations of murder and bribery. In April, federal prosecutors announced weapons charges against five former senior Blackwater executives, including its former president.”

My thanks to Dr. Ingo Hertrich, University of Tuebingen for generating these sound clips in English for readers to hear.

Verbal abuse by peers damages a child's brain

            Sticks and stones may break my bones, but words will never hurt me…  We all know how untrue that childhood incantation is.  Words do hurt.  Ridicule, distain, humiliation, taunting, all cause injury, and when it is delivered in childhood from a child’s peers, verbal abuse causes more than emotional trauma.  It inflicts lasting physical effects on brain structure.

            The remarkable thing about the human brain is that it develops after birth.  Unlike most animals whose brains are cast at birth, the human brain is so underdeveloped at birth that we cannot even walk for months.  Self awareness does not develop for years.  Personality, cognitive abilities, and skills, take decades to develop, and these attributes develop differently in every person.  This is because development and wiring of the human brain are guided by our experiences during childhood and adolescence.  From a biological perspective, this increases the odds that an individual will compete and reproduce successfully in the environment the individual is born into, rather than the environment experienced by our cave-man ancestors and recorded in our genes through natural selection.  Developing the human brain out of the womb cheats evolution, and this is the reason for the success of our species.

            When that environment is hostile or socially unhealthy, development of the brain is affected, and often it is impaired.  Early childhood sexual abuse, physical abuse, or even witnessing domestic violence, have been shown to cause abnormal physical changes in the brain of children, with lasting effects that predisposes the child to developing psychological disorders.  This type of brain scarring is well established now by human brain imaging studies, but prior to the recent study by Martin Teicher and colleagues at Harvard Medical School, taunting and other verbal abuse experienced by middle school children from their peers was not thought to leave a structural imprint on the developing brain.  But it does, according to their new study published on-line in advance of print in the American Journal of Psychiatry. 

            Young adults, ages 18-25, with no history of exposure to domestic violence, sexual abuse, or parental physical abuse, were asked to rate their childhood exposure to parental and peer verbal abuse when they were children, and then they were given a brain scan. 

            The results revealed that those individuals who reported experiencing verbal abuse from their peers during middle school years had underdeveloped connections between the left and right sides of their brain through the massive bundle of connecting fibers called the corpus callosum.  Psychological tests given to all subjects in the study showed that this same group of individuals had higher levels of anxiety, depression, anger, hostility, dissociation, and drug abuse than others in the study. 

            Verbal abuse from peers during the middle school years had the greatest impact, presumably because this is a sensitive period when these brain connections are developing and becoming insulated with myelin.  (Myelin is formed by non-neuronal cells, brain cells that are also known as “the other brain”, or glia.) 

            The environment that children are raised in molds not only their mind, but also their brain.  This is something many long suspected, but now we have scientific instruments that show us how dramatically childhood experience alters the physical structure of the brain, and how sensitive we are as children to these environmental effects.  Words–verbal harassment–from peers (and, as a previous study from these researchers showed, verbal abuse from a child’s parents) can cause far more than emotional harm. 

            Early childhood experience can either nourish or stifle brain development, and the consequences are physical, personal, and societal.             Childhood taunting and verbal bullying have always been a problem, but many feel that civility, courtesy, polite social interactions, have declined markedly from the environment that today’s adults experienced as children.  Many schools are more hostile places than schools once were, and new technologies, such as the internet, offer more opportunities for taunting and humiliation of children.  If this is true, modern conditions or attitudes that tolerate verbal abuse of children by their peers are an incubator for developing brains with abnormalities in the corpus callosum and an elevated risk of psychiatric problems.  The critical concern for ridding our environment of neurotoxins must also include “neurotoxins” children are exposed to in their social environment.

            (Note:  for new research showing an impaired ability to make moral judgments in people with defects in the corpus callosum connecting the left and right sides of their brain, see http://www.huffingtonpost.com/dr-douglas-fields/of-two-minds-on-morality_b_738916.html.)

Photo credit:  dailymail.co.uk

Are lefties different? Mirror-image people provide clues

            Most people salute the flag by respectfully placing their right hand over their heart, but not everyone does this.  That’s because some people (1 in 10,000) are born with their heart on the wrong side.  Not only their heart, but all their internal organs are swapped left for right:  liver, stomach, pancreas, gallbladder, spleen, colon, are all situated on the opposite side of the body from the familiar position depicted in anatomy books.  There are no known medical disadvantages to having your organs on the “wrong” side, a condition called situs inversus, provided, of course, that your surgeon is advised of your situation prior to scrubbing up.  This raises some interesting questions. 

             Why are people and most animals bilaterally symmetrical on the outside, but anatomically asymmetrical inside?  It is not only anatomy.  Behavior, brain function, and certain physiological processes show preferences for the left or right side of the body in both people and animals.  Individuals within a population (both people and animals) have a dominant eye and ear (usually the right)—why?  Language function, for example, is controlled by the left cerebral cortex in 97% of right-handed individuals and 66% of left-handed individuals.  Certain diseases are more common on either the left or right side of the body—breast cancer is more common on the left, and so is immune hypersensitivity.  (For an intriguing possible environmental contributor to left-sided cancer see: http://www.scientificamerican.com/blog/guest-blog/index.cfm?author=771)

             There are also curious differences in body asymmetry associated with gender.  The left foot tends to be larger in women but the right foot is usually larger in men.  In people who are hermaphroditic, the ovaries are more than twice as often on the left side of the body and the testes are on the right.  And if you were wondering…it is perfectly normal for the left side of the scrotum to descend lower than the right, a pattern that is reversed if you are a left-handed male. 

             There are some deep mysteries here.  Even if there is some advantage to having asymmetry in internal anatomy of brain and body structure, the more intriguing question is:  Why aren’t the chances of having your heart, language function, and handedness on the left or right side 50:50?  Surely a random outcome is the most natural one to generate.  There must be some very compelling reason for Nature taking sides to ensure that most of us are right-handed and only 1 in 10,000 of us has our hearts on the right.  Are lefties different? 

A connection between heart and brain?

            A skilled radiologist can see from a glance at your MRI whether you are left or right handed, because certain brain structures are either enlarged or reduced on either the left or right side of the brain.  In the vast majority of people, the right frontal lobe juts forward ahead of the left frontal lobe.  (Being right-handed myself I had long ago noticed this asymmetry in my own brain scan, but like some of the other hidden asymmetries mentioned above, I had always assumed it was an idiosyncratic mild deformity.  What a relief!  http://www.museumsinflorence.com/musei/david_by_michelangelo.html)  No one knows why this is so or what difference it makes whether your left or right frontal lobe leads, but there are several other well-known anatomical asymmetries in different regions of the brain.  Aya Ihara and a team of neurologists and radiologists working in Japan, report in the Journal of Neurological Sciences, that in people with their hearts and other internal organs swapped left for right, the frontal lobe asymmetry in their brain was also reversed. 

             This finding means that whatever genetically controlled developmental mechanisms drive the asymmetrical arrangement of your guts, they also control this asymmetry in your brain’s frontal lobes.  Using functional brain imaging the researchers also found that the language-dominant hemisphere was also swapped from the normal location in the left cerebral cortex to the right side in mirror image people.  This reversal suggests a strong genetic component in controlling cerebral dominance of brain function—in this case language. 

             One wonders about other functions predominating in either the left or right hemisphere—the Spock-like analytical logic of the left-brain vs. the creative, intuitive thinking of the right-brained artist.  But in examining other brain regions with known anatomical asymmetries, the researchers found that many of them were not reversed in people with situs inversus.  The plot thickens.  There must be multiple mechanisms controlling left/right asymmetry in different parts of the brain as well as the possibility of environmental influences.  This returns us to the central question:  does it matter which side of your brain does what? 

A fishy finding

            The dream experiment to answer this question would be to somehow reverse the normal asymmetry of the brain during embryonic development and then study the effects on the animal’s brain function.  That’s exactly what Marnie Halpern and colleagues at the Carnegie Institution of Washington have accomplished.  The researchers genetically modified zebrafish to reverse the normal asymmetry in part of the fish’s brain (the parapineal region).  Normally, the parapineal region is larger on the left side of the brain in 95% of zebrafish. 

             The researchers found that motor function and other behaviors were not altered in these mirror image zebrafish, but the fish with reversed brain asymmetry were extremely shy.  The fish with their brain anatomy reversed hovered timidly at the sides of the fish tank like a fearful swimmer clinging to the edge of a public swimming pool, rarely venturing into the ruckus of other zebrafish darting all about the tank playfully.  Their surprising finding suggests that neural circuitry connected to areas of the brain controlling fear, reward, and novelty seeking are altered when the asymmetry of their brain is reversed by genetic manipulation.

             Although there is much to be explored concerning the left-right brain asymmetry in behavior, this research suggests that if we are to understand why handedness (and asymmetry of brains) is not 50:50 in a population, we must look beyond the simple mechanical operation of the brain and examine more subtle behavioral differences associated with handedness.  These subtle differences in character traits could have advantages and disadvantages for individuals in a population.  It must be important for the success of a species to have a minority of individuals with behavioral traits that are strengthened by mirror-image reversal from the “normal” arrangement of brain and body. 

             The lesson from Dr. Halpern’s research (who happens to be left-handed) is not that left-handed people are shyer than right-handed people; clearly that is not the case.  The findings show us that as a consequence of the simple fact that there are left/right asymmetries in brain structure and function, that if some of these circuits are swapped left for right, the reverse wiring will have consequences for the wide variety of complicated functions controlled by different brain circuits.  This can include behavioral differences and character traits that affect social interaction, as well as other functions where a critical balance between novelty-seeking and fear are crucial.

            The belief that money erodes happiness is a persistent theme running through centuries of the world’s philosophers, religions, and cultural leaders.  Why?  If money is so desirable, how could it possibly spoil happiness?  A new scientific study published in the current issue of Psychological Science by Jordi Quoidbach and colleagues, proves the Quaker philosophy is correct.  Money—even the thought of it—reduces the satisfaction of life’s simple pleasures.  

       Previous studies have shown, and this study confirms, that there is a correlation between a person’s wealth and decreased ability to savor pleasant experiences.  To investigate this puzzling correlation, 374 adults, ranging from custodial staff to senior administrators, were divided into two randomly assigned groups.  The first group was shown a picture of a stack of money, and the control group was shown the same picture blurred beyond recognition.  Then the participants were given psychological tests to measure savoring ability, happiness, and desire for wealth.  The results showed that the subjects who were shown the money beforehand scored significantly lower ability to savor pleasant experiences.  Just the thought of money had diminished their ability to appreciate and savor pleasant experiences. 

             Savoring is the emotion of positive feelings, such as joy, awe, excitement, contentment, pride, and gratitude derived during an experience, and the researchers found that one’s ability to savor predicts their degree of happiness.  A second test showed the spoiling effect of money on savoring even more dramatically.  Participants were given a piece of chocolate after being shown the picture of money or a blurred photo.  Then an observer, who could not see what picture the subject had been shown, clicked a stopwatch and timed how long the person savored the morsel of chocolate.  Women, not too surprisingly, savored the chocolate significantly longer than men, but regardless of gender, those shown the picture of money before they were handed the piece of chocolate spent significantly less time savoring the chocolate—32 seconds versus 45 seconds on average.  A simple reminder of wealth can significantly diminish the pleasant experience.

             The authors conclude that access to the best things money can buy undermines one’s ability to savor life’s simple pleasures.  Remarkably, even a subtle reminder of the prospect of wealth can diminish one’s satisfaction with life’s simple pleasures. 

             As the world’s economy weakens and personal wealth diminishes, it is heartening to consider what this experiment shows:  What money gives with one hand—access to pleasurable experience—it takes away with the other by robbing our ability to appreciate simple joys.  Something to think about the next time you are considering spending cash at an expensive five-star restaurant or spending a sunny afternoon at a picnic with a bottle of cold wine, a crusty loaf of French bread, and the tangy sweetness of cheese…topped off, of course with a bite of chocolate.

  “For where your treasure is, there your heart will be also.”  –Jesus in Luke 12:22-34.

“Say you don’t need no diamond ring and I’ll be satisfied …money can’t buy me love”–Paul McCartney

Brain infection

            She was young and wild, a bit of a rebel.  The 22-year-old woman’s body art announced that message as subtly as a billboard on a highway.  No stranger to illegal drugs, she had inhaled or injected the worst of them, including cocaine and heroin.  But recently she had turned a corner.  Last month she removed her new tongue piercing only two days after getting it, and she hadn’t injected any drugs for the last 5 months.   Ironic that after cleaning up her act she should now find herself stricken with a throbbing headache that was unfazed by aspirin.  Severe nausea, vomiting, and vertigo drove her to the hospital. 

            The results of an HIV test were negative.  A neurological exam found mild ataxia (un-coordination) in her left leg, which she had already noticed.  This alerted her doctors to a potential problem in the right side of her brain in the region of motor co-ordination, called the cerebellum.  A CT scan and an MRI delivered the diagnoses with alarming clarity.  The woman was suffering from a festering brain abscess in her cerebellum.  Emergency brain surgery was scheduled to remove the diseased brain tissue and drain the infection.  Treatment with strong antibiotics was begun immediately.  Laboratory analysis revealed that the infected brain tissue was a harrowing cesspool of infectious bacteria that included Streptococcus, Peptostreptococcus, Actinomyces, and Eikenella.  If she hadn’t injected any drugs in 5 months, how did these flesh-eating bugs get into her brain?

            On the other side of the world from the New Haven, Connecticut hospital where the woman was treated, a 22-year old Israeli man, who in outward appearance might have made a compatible match to the rebellious young woman, was suddenly stricken with a high fever and profound fatigue.  The young man had always been blessed with youthful vigor and unlike the woman, he never abused illegal drugs.  Without warning the man rapidly developed global aphasia; that is, the inability to speak or write or understand written or spoken language.  His neurologists knew with certainty that his left cerebral cortex was impaired.  This part of the brain is where Broca’s and Wernicke’s areas are located, which control speech and language comprehension.  Soon the right side of his body became paralyzed. 

            A CT and MRI scan revealed 13 horrifying ring-shaped bleeding abscesses the size of ping-pong balls in the man’s brain.  Lab tests showed that he was negative for HIV and cystic fibrosis, but his blood count confirmed that his body was fighting a life-threatening infection.  There were too many abscesses to remove surgically.  A brain biopsy revealed the pus-filled brain tissue was swarming with the nasty bacteria Streptococcus intermedius. 

            This bacterium is part of the normal flora of the mouth and upper respiratory tract, but when the germ gets inside the body it forms life-threatening abscesses in the liver, brain or inner lining of the heart.  Streptococcus intermedius infections of the brain are usually the result of head trauma or complications after brain surgery, but this man had been perfectly healthy until 22 days ago.  What had happened to this man two weeks earlier?

            A medical history revealed that nothing remarkable had occurred to the man recently, except that he had received a tongue piercing two weeks before.  A common thread tied the young man and woman’s fate together in the medical literature—a link through lingual baubles to brain infection. 

            The woman would survive, but after suffering three more weeks in the hospital, the young man would lose his life to the germs that entered through the piercing in his tongue.  They invaded without causing any local infection of the tongue or producing a fever, and they silently worked their way into his brain where they turned it to pus. 

            36 percent of college age males and 62 percent of college age females have body piercings (not including earlobe piercings in women).  In women, 10 percent of these piercings are in the nose and 11 percent are through the tongue.  For college age men the rates are 1.2 and 4 percent for nose and tongue piercings.  70 percent of people with tongue piercings report complications, ranging from local infections, eroded gums, chipped teeth, and more serious systemic infections including hepatitis B and C. 

            When you think about it, this really should come as no surprise.  The mouth and nasal passages are a veritable incubator of nasty disease-causing bacteria.  We all suffer sore throats, respiratory and nasal infections as a result; some of them quite serious.  The surprising thing is how resistant our vulnerable tongue is to infection—unless you poke a hole through it.   The tongue is shielded with a thick tough outer layer of skin and it is bathed continually with saliva containing antimicrobial proteins.  In contrast to earlobes, the tongue is richly supplied with blood, which provides an invading germ ready access to the blood stream, to spread infection throughout the body.  The veins that drain the tongue connect directly to the internal jugular vein, which is a direct route into the brain.  Earlobes are cleaned with surgical antiseptic before piercing them, but the tongue is not prepped before stabbing a hole through it.  Mouthwash usually precedes the needle, but that is more for the benefit of the person doing the piercing. 

            Disease attacking the brain is perhaps the most dreaded of all disorders for most people.  You can’t avoid most of them, but some of them you can.

—

From a study by Herskovitz, et al., published in the October 2009 issue of the journal Archives in Neurology, and Martinello and Cooney, published in the January 2003 issue of the journal Clinical Infectious Diseases.

To learn more about brain infections and how the body fights them see the new book: The Other Brain, by R. Douglas Fields, published by Simon and Schuster, 2010.  http://theotherbrainbook.com

Photocredit: Herskovitz, et al., (2009)  Arch. Neurol. 66:1292.

Is captivity driving killer whales mad?

             Talk turned to the deadly dangers of a fisherman’s life at sea.  Enormous waves capsizing a tiny vessel in a ferocious storm and sending it to the bottom in minutes; becoming lost in a blinding fog so thick the familiar bow of the boat is gone, and crashing on the rocks; becoming ensnarled in the rigging and being towed under with the crab pots to a watery grave.  John Hurwitz, a white whiskered, salty Dungeness crab fisherman speaking from the deck of his boat the Irene Marie confessed his greatest fear to me.  “The only thing that scares me out there are the killer whales.  When I see one we clear the deck.  I’m worried that they will leap across the deck and grab me.”

            That was three weeks ago, before the circus whale known as Tilikum, snatched its trainer, Dawn Brancheau by her hair and pulled her into the tank at Sea World.  Shaking her like a rag doll, Dawn Brancheau was killed in front of hundreds of shocked spectators.  Disillusioned and confused the public has tried to understand the dysfunctional psyche of this beloved animal turned murder.  This particular individual is a serial killer.  This is the third trainer this whale has killed. 

            As a marine biologist my specialization was shark research, but the most vicious attack I ever witnessed at sea was a pod of killer whales tormenting a helpless grey whale.    Grey whales are much larger than killer whales, but the killers come in packs.  Like a mob, the killer whales had circled the grey whale turned belly up defensively to protect her vulnerable belly.  The killers raided in turns from every direction as the rest of the pack circled the helpless animal.  Taking turns a killer would leap out of the water with the amazing speed and power of a dolphin and crash their 9 tons of weight down on the grey whale as the others bit at the victim as she was driven under or biting when she rolled over to gasp a quick breath through the blowhole on the top of her head.  Killer whales go for the grey whale’s rich tongue.  They leave the carcass for the sharks and other scavengers.

            These whales were named by people of the sea who knew them well.  All animals prey on some other life form, but these whales are called killers.  They were given this name because these animals have the intelligence to organize themselves into social groups and attack ferociously with military cunning.  Invincible at their pinnacle atop the food chain, killer whales are the supreme hunters in the world’s oceans. 

            But to call them murders, and to wonder in disbelief how an animal so beloved and nurtured by human beings could become psychotically deranged and attack its handler, is to mistakenly project human qualities on an animal that has no concept of human beings or the ability to comprehend the capabilities that our remarkable brain provides.  The human brain so far outstrips the mental abilities of every other animal on the planet, comparison between the human mind and the cognitive abilities of any other animal is absurdly disproportionate. 

            Whales have the biggest brains on the planet in absolute size, and in proportion to body size the whale brain is one of the largest.  Throughout the animal kingdom brain size correlates with the social abilities of animals.  For the same reason evolution endowed Homo sapiens with a large brain, whales, and some species of sharks, have very large brains because they need them to coordinate their sophisticated social interactions.   But you cannot gauge intellect simply with a meat scale or a ruler.

            Superficially the whale brain somewhat resembles the human brain.  The whale’s cerebral cortex is highly convoluted—looking like kinky hair in comparison to the wavy convolutions of the human brain, but the whale cerebral cortex is thin and the cellular structure is much simpler than that of the human brain.  The human cerebral cortex has six layers of intricately wired brain cells in the cerebral cortex.  In animals like cats and raccoons the cellular structure of this part of the brain responsible for higher level cognitive function in humans is more complex than it is in whales. 

            The tragic death at Sea World has opened debate about whether the confines of captivity are so cruel they drive these intelligent creatures mad.  Whales are wondrous creatures, but the reality is that the true nature of these animals is unfamiliar to most.  People are eager to project human thoughts and emotions on creatures that are adoringly intelligent–for an animal.  Adoring pet lovers who tenderly care for a dog or cat never feel that the abnormal life they provide these creatures is cruel, even though a dog may bite and a cat may scratch its owner.  These whales, called killers, are simply doing what they do.

            The horrible nightmares.  An American soldier serving in Iraq reaches out for support in his recent website post.  “Last night I dreamed I was flying in a Blackhawk to another FOB and blood was covering the seats and the floor of the bird. There was so much that I was scooping it out the door with my hands. It’s starting to effect my sleep a lot.” 

            Serious sleep disturbance from nightmares is one of the most debilitating consequences of post-traumatic stress disorder (PTSD), affecting 70%-87% of patients suffering the psychological trauma.  Psychiatrists empty the drug cabinet in a trial-and-error search for a medicine that will bring relief to people with PTSD.  Everything from antidepressants, anxiolytics, antipsychotics, sedatives, to mood stabilizers is prescribed for PTSD.  Now there is a surprising new approach:  grandma’s high blood pressure medicine.

            A connection between high blood pressure and nightmares terrorizing people with PTSD seems odd at first, until you consider what the body’s natural response to stress is.  The first switch thrown in our fear response jump-starts our heart rate powering a surge in blood pressure.   This familiar adrenalin-fueled boost is the body’s way of revving up all systems for the fight or flight response to any life-threatening situation.  The high blood pressure medicine, prazosin, dampens adrenalin’s effect on the heart and blood vessels by blocking receptors for the hormone.    High blood pressure medicine is the newest approach to treating PTSD, and the studies are still underway, but the data thus far show that seventy-five to eighty percent of PTSD patients who try prazosin stop having nightmares and sleep through the night with normal dreams. 

            But how could reducing blood pressure have any effect on nightmares and reliving horrific memories of traumatic events?  The answer is that adrenalin’s effects are hardly limited to our cardio-vascular system; adrenalin also has a powerful effect on the brain.  Any event that is accompanied by extreme stress is burned into memory by adrenaline stamping the experience as life-threatening and something that should never be forgotten.  In contrast to the repetition necessary to write most events into long-term memory, a traumatic event is seared into memory permanently after one experience.  You will never forget any truly life-threatening experience, and the adrenalin surge is what marks that experience as life-threatening to encode it permanently into memory.

            A similar high blood pressure drug, propranolol, works the same way, and it is being used to “erase” traumatic events from memory by having the patient recall the traumatic event that caused the PTSD while the adrenaline response is dampened with the medication.  The memory loses its association with danger when the adrenalin signal is suppressed, and it begins to fade.  This forced recall re-enacts what happens naturally in our head every night at rest on our pillow.  Recent research shows that as we sleep we unconsciously sort through our daily experiences, associate them with other memories, and decide which ones to discard and which to keep.  So using high-blood pressure medicine to relieve nightmares and dampen the horror of traumatic memories makes good sense in light of how memory is stored.

            For more on the subject of memory and erasing traumatic ones, see my articles in Scientific American Mind and Odyssey Magazine below.

References

Berger, W., et al., (2009)  Pharmacologic alternatives to antidepressants in posttraumataic stress disorder:  A systematic review.  Progress in Neuro-Psychopharmacology and Biological Psychiatry  33: 169-180.

Fields, R.D. (2008)  Erasing Memory Odyssey, May/June 6-11

Fields, R.D. (2008)  Lost, Odyssey May/June 12-15.

Fields, R.D.  (2005)  Erasing memories.  Scientific American Mind November 16:28-37

            http://www.scientificamerican.com/article.cfm?id=erasing-memories

Fields, R.D. (2006) Unforgettable.  Odyssey November, 38-40. 

Fields, R.D.  (2005) Making memories stick.  Scientific American  292 (February), 74-81.

            http://www.scientificamerican.com/article.cfm?id=making-memories-stick

Fontaine, S (2009)  Blood pressure pill slays nightmares.  The Washington Post, Dec. 31, 2009,     p. A15.

Miller, L.J. (2008)  Prazosin for the treatment of posttraumatic stress disorder sleep disturbances.  Pharmacotherapy 28: 656-666.