Concussions: Banging away at your brain

by Topher Toffoli

Rock Dennis tackles Taylor Wardlow by John McStravick

Injuries are becoming more prevalent in high contact sports as players move towards being bigger, stronger, and faster. In ice hockey as many as 66% of hockey players have experience a head injury known as a concussion, which is a mild to severe trauma to the brain caused by the soft brain tissue hitting the hard skull.  Injuries can cause serious long-term damage to the parts of the brain responsible for memory, judgment, social conduct, reflexes, speech, balance and co-ordination.  These parts, which are located in the frontal and parietal lobes, are hit against the brain and damaged by bleeding and bruising from contact with the hard cranium. Researchers at Albert Einstein college of Medicine used diffusion tensor imaging to find that damage from concussion can cause loss in higher level thinking from planning evens to personality change. They also found that 30% of people sustaining these injuries had long terms affects associated to memory and personality.

Although this problem is very serious since the diagnoses of a “Concussion” have become so main stream players are unaware of the consequences and thus return to play too soon. 40% of younger players and 30% of adult players could not recognize symptoms and believed that they could return to play after two days with mild headaches. Researchers have found that by being diagnosed as having a concussion instead of re-wording it as brain trauma can have drastic effects on the perception of the injury to the patients. Patients diagnosed with a concussion rather than brain trauma were more than twice as likely to return to school and athletics before doctors orders allowed them too. The simple familiarity of the word concussion is putting people at risk. This is due to the mere exposure effect, meaning that the more you are exposed to a stimulus, in this case a word, the more positively you will perceive that stimulus. Since people have heard and can associate concussions with others they know they do not take it as seriously as when the more specific term of brain trauma is used.

Also athletes wishing to return to sports in our win-driven sports world are willing, in their ignorance, to put there bodies in harms way for the “win at all cost” mentality. New rules in safety such as helmets and rules prohibiting fighting are steps that are being taken in hockey to prevent further injuries however players and parents must be educated so that they know, fully, the risk they are putting themselves in.

References

St. Michael’s Hospital (2009, June 1). Minor League Hockey Players Unable To Identify Concussion Symptoms, Study Says. ScienceDaily. Retrieved March 5, 2010, from http://www.sciencedaily.com­/releases/2009/05/090527121051.htm

McMaster University (2010, January 18). Concussions not taken seriously enough, researcher finds. ScienceDaily. Retrieved March 5, 2010, from http://www.sciencedaily.com­/releases/2010/01/100118001721.htm

Albert Einstein College of Medicine (2009, August 25). Strong Link Found Between Concussions And Brain Tissue Injury. ScienceDaily. Retrieved March 5, 2010, from http://www.sciencedaily.com­/releases/2009/08/090824115905.htm

Something eating your brain?

by Alex Lee

…non fidarsi è meglio – my scared cat / gatto by Paolo Margari

One of the stranger tropes of science fiction is the idea of mind control. A well-known example of a similar phenomenon in nature is the rabies virus, which causes dramatic changes in the behavior of infected individuals. Lacking the full power of a mind-ray, but much closer to reality, is the protist (or single celled organism) Toxoplasma gondii.

Toxoplasma can infect nearly all warm-blooded mammals, and has two stages of infection, one active and one dormant. Relatively unknown until the end of the 20^th century, Toxoplasma became a subject inquiry when AIDS compromised patients began to exhibit encephalitis and coma as a result of infection. Since then it has been eclipsed by a multitude of other issues, and a 2007 National Health and Nutrition Examination Survey linked study found 10.8% of persons 6-49 in the U.S. tested positive for Toxoplasma infection(Jones et al. 2007).

Research on the organism’s effects on human and animal subjects has been slow due to the difficulty of studying an infectious agent with two activity levels such as Toxoplasma. T. gondii has been found to infect nearly all mammals, whether by accidental digestion of spores or consumption of infected meat. Early research on rats shows that infected rats are more active than uninfected rats, and do not exhibit the innate rat fear of cats and cat-related smells such as urine (Lafferty, 2005). Research suggests that these behavioral changes provide a way for Toxoplasma to spread to cats, which are its primary carrier in most countries. .  Humans that are affected by T. gondii do not exhibit such dramatically different behavior, but new diagnostic techniques such as PCR (which rapidly and cheaply reproduces DNA)  have shed a great deal of light on Toxoplasma, which is now being implicated in several psychological disorders.

Most instances of toxoplasmosis, or infection with Toxoplasma, are in older adults, for whom infection seems to slowly induce changes in personality and behavior. Infected individuals may have slightly slower reaction time than non-infected individuals, and have a weaker capacity to focus on simple tasks (Havlicek et al., 2000). A long-term study of individuals in the Czech army found that individuals infected with T. gondii are 2.5 times as likely to be in a car accident than uninfected same-aged soldiers (Flegr, Klose, Novotna, Berenreitterova & Havlicek,, 2009). Schizophrenia is also more common in individuals exposed to T. gondii,and a recent study on schizophrenic patients found elevated Toxoplasma related immune cell levels (Torrey & Yolken, 2003). Strangely, anti-schizophrenia drugs have been shown to reduce the ability of Toxoplasma to replicate itself. More mundane, but no less bizzare effects include individuals repeatedly self-scoring themselves differently than peers on personality questionnaires. Personality effects differ with gender; a survey of infected women in Czechoslovakia found higher likelihood of self-scoring as warm-hearted, conscientious, and moralistic than non-infected women (Lafferty, 2005). Men involved in the study scored themselves in exactly the opposite way as the women.

Infection appears to last indefinitely. However, despite the fact that the dormant form of the infection is extremely common, few people experience the active form, which superficially resembles the flu. The only people for whom this active infection is dangerous in the short-term are those with weakened immune systems, such as AIDS patients or pregnant women. Women who are infected during pregnancy can spread the infection to their children, with children at birth exhibiting symptoms ranging from mild rash to hydrocephalus (water in the brain) and death (Holliman, 1995). More concerning is the result of Yolken and Torrey, a study of individuals logged in the Kaiser Hospital birth database which found that 66.7% (82/123) of children born to mothers infected with Toxoplasma develop schizophrenia related disorders. Another pressing finding of the study was that a startling 40-70% of the children of infected mothers that were not diagnosed with schizophrenia related disorders later developed learning or movement disabilities.

Does video gaming make you hostile?

by Curtis Smith

Art of Video Games Exhibit 15096 by tedeytan

Videogames are an immensely popular form of entertainment in the United States. In fact, in a national survey conducted by the Pew Internet & American Life Project (2008) of a representative proportion of youth ages 12 to 17, approximately 99% of boys and 94% of girls say that they’ve played some form of videogames. You would certainly be hard-pressed to find a person within this age range that has not played a videogame. Typically, studies have been centralized in the detrimental effects of videogames, of which can be called anti-social behavior. However, recent studies have demonstrated that conversely, exposure to pro-social content can increase pro-social behavior.

The primary argument of the opponents of videogames is against the violent ones. Considerable evidence has indeed been mounted in favor of these claims. In sum, violent videogames promote hostility, anxiety, and violence (Bushman & Anderson, 2002).  In an experiment to test this theory, a pool of randomly assigned undergraduate students played one out of four nonviolent or violent games (Bushman & Anderson, 2002). The subjects would proceed to play three morally unclear story stems. After each story stem participants were asked to state their expectations about the main character’s aggressive behaviors, thoughts, and feelings. The results clearly demonstrated skewedness towards aggressive responses, for those who had played aggressive games. After playing a violent game, players attributed over 50% more hostile actions and thoughts to the story character.  The authors raised the possibility  that repeated exposure to these short-term effects can contribute to an aggressive long-term personality.

Despite these findings, it is notable to consider that the game industry has expanded. Violence in gaming is still prevalent and perhaps preferable to many gamers. But the types of games that people are playing now are complex, thought provoking, and intelligent. The dangers of a young person consistently playing a game such as Gears of War 3 in which explicit language and violence is pervasive throughout can be readily understood. But why deny someone access to a game such as Portal 2, which is mentally stimulating, challenging, and filled with witty humor? Rather, perhaps parents should manipulate what types of games they let their children play.

Recent studies have emerged illustrating potential positive effects of videogames. In one study by Greitemeyer and Osswald, participants were asked to partake in two experiments (Greitemeyer & Osswald, 2011). First they played either Lemmings as a pro-social videogame or they played a neutral game, Tetris, for ten minutes. The first game was employed as a game in which the participants would save the beings by leading them to the exit. The second game served as a basis for comparison. After they completed the videogames, the subjects, as a “manipulation check,” filled out a questionnaire indicating how pro-social the game was and measures of their liking of the game (Greitemeyer & Osswald, 2011) Afterwards, the participants performed what is known as a lexical decision task. A string of words (Pro-social words, neutral words, and non-words) would appear on screen and the subjects were asked to identify whether it was a word or not as quickly as possible.  Subjects recognized the pro-social words faster after playing the pro-social game, compared to after they played the neutral game.

So what do these results mean? It represents evidence that playing a pro-social videogame primes pro-social thoughts in the cognitive network. Played consistently over time, the thoughts could manifest themselves in a person’s actions, thoughts, etc., just as an anti-social game would induce the opposite. Perhaps videogames are potentially more beneficial than any gamer could have thought.

References

Bushman, B. J., & Anderson, C. A. (2002). Violent video games and hostile expectations: A test of the general aggression model. Personality and Social Psychology Bulletin, 28(12), 1679-1686.

Greitemeyer, T., & Osswald, S. (2011). Playing prosocial video games increases the accessibility of prosocial thoughts. The Journal of Social Psychology, 151(2), 121-128.

Pew Internet & American Life Project (2008, September 16).  Teens, Video Games and Civics.  Retrieved May 4, 2012 from Pew Research Center Publications, http://pewresearch.org/pubs/953/

Can exercise treat drepession?

by Ava Sadeghi

Run! by Steve Garner

Every morning, you wake up, brush your teeth, go for a run, and then head to work. If you are stressed out, unhappy, or concerned, daily exercise can lift your moods and make you happier. Exercising and getting into a routine that you enjoy can relieve depression, anxiety and ultimately increase your happiness.

In recent studies, it has been shown that exercise works well for depression patients. Psychologists have been using exercise as a form of medication and treatment for many of their anxiety and depression patients (UT Southwestern Medical Center, 2011).

A clinical psychologist, James Blumenthal, at Duke University set up an experimental study to see the connection between mood and exercise. In this study, patients with a major depressive disorder were put into four groups: supervised exercise, home-based exercise, antidepressant therapy, and a placebo pill. After several months of treatment the study showed that exercise effects were similar to antidepressant medications.

A year later, Blumenthal, followed up with the patients and found that the patients who kept exercising did not go into remission. They still had low depression scores. With this study, psychologists have now started to couple antidepressant treatment with exercise, to increase mood and lessen depression.

Not only can exercise improve moods, but it can relieve anxiety as well. Jasper Smits of Southern Methodist University in Dallas performed an experiment involving 60 subjects with anxiety disorders.  These subjects were asked to take a carbon-dioxide challenge test. This test triggers symptoms of panic attacks. According to this study, Smits concluded that people with high anxiety were less likely to panic if they had high activity levels. This finding supports the idea that exercise can help lessen panic attacks (Weir, 2011).

The next step is figuring out why exercise brightens your mood. There are not many studies on this, but many psychologists believe that it has to do with increasing antibodies, endorphins, and other neurotransmitters.

Superstition may be good for you

Rome Braves by The Suss-Man (Mike)

by  105 student

To the detached observer, athletes may seem like a strange group of people, performing irrational routines in preparation for an event. Perhaps you have heard that Michael Jordan wore blue University of North Carolina shorts under his Bull’s uniform for good luck or that National Hockey League goaltender, Patrick Roy, was said to have talked to the goalposts throughout games, or noticed that Tiger Woods always wears red on Sundays. If you have ever played a sport, you or your team may have had certain rituals such as wearing purple socks on game days or eating waffles at the previous meal.

Superstition is generally first developed in hindsight, for example: an athlete reviews a performance and then establishes cause and effect between certain circumstances such as wearing green socks and playing well. In 1948, B.F. Skinner studied superstitious behavior in pigeons. After a pigeon was reduced to 75 percent of its weight (when well fed), a food hopper was presented at regular intervals into the pigeon’s cage. In the majority of cases, the birds started to perform distinct behaviors such as turning counter clockwise or swinging the head and body in a pendulum motion close to the time the food was presented. Even though there was no actual causal relationship, the birds continued to perform certain behaviors presumably because of an initial coincidence. By definition, superstitious actions do not have any inherent value yet many athletes still refuse to change their behavior. Are they wrong or simply stubborn by acting this way? Many studies indicate the opposite, superstitious behavior does serve a purpose.

Chance plays a part in the outcome of virtually all sports, creating a relatively uncertain environment. Optimal athletic performance demands a heightened mental state known as the flow state or being in the zone,essentially a good match between the demands of the sport and the abilities of the athlete (Marr, 2001). A survey of male and female athletes at the University of Western Ontario indicated that athletes use superstitions to regulate their emotions in stressful situations such as sporting events. Though superstitious behavior may have no rational foundation, athletes believe they have a greater sense of control over the outcome of the situation, helping them to reach an optimal mental state (Burke, 2006).

Regardless of an athlete’s specific rituals, superstitions may serve an important role in athletic performance. Remember this the next time you hear about an athlete’s strange pregame routine.

References

Burke, Kevin L. (2006). An Exploratory Investigation of Superstition, Personal Control, Optimism and Pessimism in NCAA Division I Intercollegiate Student-Athletes.  Athletic Insight, 8(2). Retrieved April 21, 2010 from http://www.athleticinsight.com/Vol8Iss2/Superstition.htm

Gregory, Jane C. and Brain M. Petrie. (1972).  Superstition in Sport.  University of  Waterloo.  Presented at the Fourth Canadian Psychomotor Learning and Sports Psychology Symposium. Retrieved from http://www.eric.ed.gov:80/ERICDocs/data/ericdocs2sql/content_storage_01/0000019b/80/34/0f/45.pdf

Marr, Arthur J. (2001). In the Zone: A Biobehavioral Theory of the Flow Experience.  Athletic Insight, 3(1). Retrieved from http://www.athleticinsight.com/Vol3Iss1/Commentary.htm

Skinner, B.F. (1947). Superstition in the Pigeon. Journal of Experimental Psychology, 38, pgs. 168-172. Retrieved March 5, 2010 from http://psychclassics.yorku.ca/

Skinner/Pigeon/

TV for Babies?

by Nicole Bronson

Wathing TV by roxeteer

Did you ever watch Barney or Sesame Street growing up?   Nowadays, in addition to Barney and Sesame Street, there are even more TV shows aimed at kids, ranging from a sponge that lives under the sea to a little Spanish-speaking girl who explores with her monkey friend!  There is even an entire TV channel, BabyFirst , which is devoted to TV programs for babies.  Technology, TV especially, seems to be more frequently targeting young kids as well as babies (Christakis & Zimmerman, 2009).  And despite warnings  that early TV exposure should not occur in children under 2 years of age, many parents still allow their children to watch TV younger than this age.  My best friend claims her 2 and 3-year old niece and nephew first started watching TV as soon as they were born! What parents may not know is that by allowing their children to watch TV at very young ages, they may be negatively impacting their children’s future cognitive performance and brains.

A  study conducted at Wake Forest University (2007)  investigated whether or not watching teletubbies teaches 15-24 month-old children new words.  The lead researcher, Marina Krcmar, compared 15-24 month-old children’s abilities to learn new words from teletubbies to their abilities to learn new words from a present adult speaker.  Interestingly, children were much better learning words from responsive adults than from the television program.  Thus, it seems learning new words at very young ages entails interaction with present, human teachers.  Children under the age of 2 may not be reaching their full cognitive and language potential learning from a TV, instead of an adult.

Also acknowledging the importance of determining the relationship between television children’s learning abilities,  the American Academy of Pediatrics (AAP) recently released a new policy statement  about technology use by children younger than two.  The new statement was created in lieu of technological advancements and new research that has been conducted since the original policy statement was released in 1999.  The original policy statement discouraged media exposure for children under the age of 2.  Meanwhile, the new policy statement also discourages media exposure for this age group, while additionally providing more scientifically backed reasons for why media exposure should be avoided.  Similar to the Wake Forest University study, this new policy claims children under 2 cannot comprehend what they are watching, and therefore do not get much educational benefit from it.  Additionally, media exposure may exert negative health effects on children under age 2, just as it has been shown to do in preschool and elementary school children.  These negative health effects may include increased aggression, attentional problems, sleep troubles and obesity.  Even simply having the TV on in the background may have negative effects on children under age 2.  Focusing on the TV rather than their child, parents may inadvertently take away from the quality of parent-child interactions.  This long list of potential adverse effects due to early media exposure was sufficient enough for the AAP to reaffirm the claim they made in 1999 and continue to discourage media use by children less than 2 years of age.

With an increasing number of children under the age of 2 watching television, it’s important to understand if television does actually induce detrimental effects and if so, how exactly it exerts these effects.  Adverse effects may be influenced by television’s impact on brain development that is occurring very rapidly in children at an early age (Siegler, DeLoache & Eisenberg, 2011).  Although babies’ are born with the majority of neurons they will have for the rest of their lives, many changes occur within and between their neurons, especially early in life.  One such change that takes place is called arborization, where neurons’ dendrites grow and differentiate.  It literally looks like a tree! The development does not end there, however, as neurons then begin to form connections with thousands of other neurons in what is called synaptogenesis.  So many connections are made, however, that some must be pruned.  This synaptic pruning—loss of neuronal connections—occurs in about 40% of the synapses and is mediated by a “use it or lose it” phenomenon.  Basically experience is key in determining which synapses are used and therefore kept and which synapses are not used and therefore pruned.  Sensory experiences babies encounter early on in life are extremely important then for signaling, which neurons are appropriate to maintain and which are appropriate to prune.  The major concern with TV exposure for babies is that it takes away from critical sensory experiences they would have had if not watching TV.  As most TV watching is a passive experience, children are not being exposed to different types of stimuli—olfactory, tactile, gustatory—they may be exposed to if not watching TV.  A member of the AAP Council on Communication and Media, Dr. Brown, recommends that babies, instead of watching television, engage in unstructured play.  Unstructured play is important for motor development, problem solving and creative thinking and thus contributes greatly to sensory experiences.  Furthermore, with less TV distractions, parents and children may be able to interact more, potentially leading to better language development in the child.  Physical interactions are key for sensory development and cannot be sufficiently replaced by a video.

This is your brain on diabetes

by Clayton Masterman

Photo by Andrew Scott

It is easy to think of memory as a cognitive process, but like everything in our brain it depends on physiological processes to function. New research has revealed that diabetes can have physiological effects that are severely detrimental to memory. Diabetes comes in two forms, both of which have been linked with the degradation of mental processes. Type 1 diabetes occurs because the body fails to create enough insulin, and type 2 occurs because the body’s cells are unable to use the insulin correctly.  Insulin is a hormone secreted by the pancreas that helps cells absorb glucose and create energy. In diabetes blood sugar levels become too high and various complications arise.

Recent studies have shown that both types of diabetes are having an impact on cognitive abilities and memory. Sometimes a diabetic patient can experience diabetic ketoacidosis, which occurs when the body reaches a state where it burns fat for energy instead of sugar. This can have severe complications, the worst of which being a coma.  According to a recent study children that have gone through diabetic ketoacidosis perform worse on memory tests than other children. This research was based on children with type 1 diabetes, but these results aren’t isolated to this form of the disease.

A study performed by Dr. Tali Cukierman-Yaffe found that diabetics are 1.5 times more likely to experience a decline in cognitive performance and 1.6 times more likely to experience dementia than individuals without diabetes. This is complicated by the fact that diabetes is an intensive disease to manage; patients must remain constantly vigilant. If a treatment cycle begins to get off course, things quickly get out of control.

The reason for these effects is not entirely understood. Several studies have examined the influence of other factors such as stress and determined that they increase the risk of mental decline in patients, but that they are not the sole cause. Other studies are pointing to cardiovascular damage caused by diabetes as a mechanism for cognitive decline, leading to a form of dementia similar to pure vascular dementia. (Biessels et al, 2005)  Until the cause is confirmed and a treatment is developed, patients are left with little hope of a way to prevent these issues from occurring. The only real recommendation that exists is for patients to keep on their treatments to ensure that blood sugar levels remain at normal levels. New cases must be diagnosed immediately to make sure treatment begins as soon as possible. Hopefully soon we’ll confirm the cause of this problem and be able to combat it more effectively.

Is screen time ruining our face time?

by Chelsea Boccagno

Everett and Monroe share screen time by cafemama

Imagine yourself in your room, waiting for your friend to come by. He soon enters wearing a yellow cap with dark purple splotches that you find absolutely horrendous. You might instinctively gasp, or widen your eyes. Even worse, he may ask your opinion, and he’ll know from your unconvincing tone that you’re lying when you say you like it. Now imagine that friend sending you a picture of the hat through an online chat. Unable to see or hear you, he can’t know your initial reaction. When he asks your opinion, he won’t know from your typed sentence (“I like it!”) that you actually despise it. It’s obvious that face-to-face communication differs from online interaction: when online, you can’t hear the person’s voice or see any facial expression (and therefore must assume people’s emotions through their use of emoticons or, say, the caps lock button). Regardless, both children and adults use home computers as a frequent means of communication. Yet children are still undergoing social development. Does Internet communication then impact a child’s social growth and understanding of others?

According to a 2005 Kaiser Family Foundation survey, American children between ages 2-17 spend more time using screen media than participating in any other chosen activity, including outside play (Rideout, 2005). Additionally, enhanced access to the home computer increases the child’s total amount of screen time (video games, television, etc.), resulting in decreased face-to-face interaction (Stanger & Gridina, 1999). Modern children just aren’t going to the playground anymore. They might consequently satisfy their urge to interact with others by playing computer games, or having an online conversation. But for children, play has social benefits such as learning how to share and cooperate. Therefore increased indoor time might negatively affect children’s social competence regardless of whether they’re talking to others online.

Besides impacting face-to-face playtime duration, computer interaction may alter the way in which children emotionally understand others. A recent New York Times article expresses concern about technological interaction destroying the intimacy and emotional feedback of face-to-face communication.

Doodle your way to better memory

by Daniele Selby

Doodle and photograph by itselea

How often do you daydream in class? Or when your mother lectures you, or when your friend tells you minute by minute what happened in the their day. Chances are you remember very little of what was said in those encounters. The same goes for studying while watching the television – sometimes it makes it harder to remember what you read. Generally, multitasking while trying to acquire new knowledge has a negative effect. Multitasking while learning can interfere with the recollection of the knowledge later (Schaffhausen, 2006). Yet interestingly, a new study has found some evidence that a specific kind of multitasking, doodling to be exact, can help memory recall.

At Plymouth University researchers performed memory tests on 40 volunteers. During these tests the subjects were asked to listen to a phone call and recall the names and places mentioned during the call afterwards. The call lasted two and minutes. Half of the volunteers were asked to doodle by coloring in shapes on a piece of paper, during the phone call. The subjects were not required to do so neatly, or with any amount of detail and attention. The other half were allowed to do as they pleased during the call. All the subjects were warned that the content of the phone call would be rather un-stimulating, and none were told this was a test of memory. Following the phone call the subjects were asked to explicitly name eight places and eight names mentioned during the call. On average, those who doodled recalled 7.5 of the required pieces of data while those who did not doodle only recalled 5.8.

It is believed that those who doodled were better able to recall the contents of the phone call because they stayed engaged during the call, rather than daydreaming or allowing their minds to wander. While doodling is a form of multitasking and might sound distracting, the level of attention and engagement which takes place while doodling – not drawing – is significantly less than that which takes place when day dreaming. People are more detached from their doodles than they are involved in their daydreams.

When testing memory and/or attention, second tasks are often used to block a particular mental process. If that process is essential to the performance of the main cognitive task at hand, then the performance of the task will be affected. The performance of the task is likely to be impaired if the second task interferes with the mental process. But this does not seem to be the case with doodling. Perhaps the reason we are inclined to doodle in the first place is that it helps us recall things we learn. There is no certain conclusion yet as to why doodling seems to help recall, but maybe this is evidence enough for all of us students to start scribbling.

References

Maron, D. F. (2009, February 26) Doodle Zone. Newsweek. Retrieved March 3, 2010, from http://www.newsweek.com/id/186738

Schaffhausen, J.  (2006, July 25) Multitasking May Harm Memory. ABC News. Retrieved March 4, 2010 from, http://abcnews.go.com/Health/story?id=2230735

Wiley-Blackwell (2009, March 5). Do Doodle: Doodling Can Help Memory Recall. ScienceDaily. Retrieved March 4, 2010, from http://www.sciencedaily.com­ /releases/2009/02/090226210039.htm

Sinister, or even-minded?

By Heather Kobayashi

Photo by Jeff the Trojan

There’s more to being a lefty than just which hand you write with.  That sentence may sound wrong to some, but a growing body of research shows a many unexpected differences between different-handed individuals.

In everyday speech, there is seeming equivalence between “right” as opposed to wrong and “right” as opposed to left; however, there are some advantages to being “sinister,” or “gauche,” both originally words for left which have become pejorative in modern language.  Left-handers have had disproportionate representation in the White House: including President Obama, 18.6% of US Presidents (8/43) have been left-handed, approximately double the percentage in the general population.  Recent research also suggests that left-handers have a more accurate body sense than right-handers: when asked to estimate arm length, left-handed people estimated both arms as being the same length, while right-handed people tended to underestimate the length of their left arms.  Similarly, left-handed people estimate that both of their hands are the same size, whereas right-handed people estimate that their right hand is larger.    Researchers theorize that this difference indicates a variance in neural networks, the physical pathways of the brain, with right handed people devoting more brain matter to mapping of the right side of their bodies.  Left-handed people, instead of having a larger brain map of their left sides, devote neural space about equally to both halves of their bodies–a decidedly less lop-sided approach.  In fact, lateralization, as distribution of functions between the hemispheres is called, has garnered attention particularly where handedness is concerned.

Brain lateralization may relate to some of the disadvantages of being a lefty.  Geschwind and Behen (1984) found a correlation between left-handedness and a host of immune and respiratory disorders as well as some learning and language disorders. They theorized that the diseases and disorders, brain lateralization, and handedness itself are all due to higher pre-natal testosterone exposure; however, they were also quick to speculate that there are some disorders which have lower occurrence rates among “sinistrals” and cited the higher than average rate of left-handedness in highly skilled professions such as architecture as evidence that left-handed people are not overall less intelligent or healthy.  More recent research has cast some doubt on this theory, asserting that the hypothesis itself is ill-defined (Bryden, McManus, and Bulman Fleming, 1994).  Geschwind and Behan failed to specify what levels of handedness and lateralization were supposed to correlate on the continuums of both scales and a meta-analysis of psychological research shows no particular support of the 1984 findings.  Nevertheless, they still remain heavily cited because no stronger model of handedness has emerged. In addition, studies do show that lefties live, on average, 3 fewer years than their dexterous colleagues (Myers, 2007).  This phenomenon may have its roots in–rather than a psychological difference–the greater number of workplace accidents that befall left-handed people because of mechanical systems designed for righties (a more severe form of the “there are no left-handed scissors” phenomenon in my kindergarten classroom).  Identical twins often have different handedness, so some factor besides genetics must be in effect, but there is also high heritability of the trait (Myers, 2007).  Thus, it remains unclear exactly how handedness, health, and the brain are related.