Brain Lateralisation and The Left-Handed Dilemma - a Psychological Viewpoint on handedness
Left Handed Brain Lateralisation
Animals exhibit equal paw preference, while13% of the human population display left–handedness, leaving the majority right-handed or ambidextrous[i]. A suggestion for this phenomenon is the development of elaborate language consisting of grammar and intricate components unique to humankind.[ii] Most humans lateralize language production in the brain’s left hemisphere[iii], which may explain why most people are consequently right-handed.
Genetics provide a more convincing explanation. When both parents are left-handed, chances of a left-handed child is 26%[iv]; in families like the British Royal Family left-handedness is hereditary prejudiced.[v] In fact scientist have discovered the LRRTM1 gene is likely responsible for traits such as left-handedness[vi].
Another reason cites birth stresses where mothers aged over 40 have a 128% chances of a left-handed baby[vii]. Also, high levels of prenatal testosterone increase the odds of a left-handed baby[viii]. Alternatively, societal culture could have converted multitudes of born left-handers into right-handers, when the damnation of left-handers prompted parents to force-change their child’s handedness through imitation in order to marry them off and save embarrassment[ix].
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Popular Left-handed products
Left-handers face many challenges in this right-handed world. Everyday examples include how lecture tables in schools force left-handers into unnatural postures, injury resulting when they incorrectly grip and apply kitchen appliances, especially scissors, peelers, can-openers…In public areas like bathrooms and train stations, left-handers inadvertently accidentally blast tapwater when they twist taps the wrong direction, and blunder when they tap their access cards but walk through the wrong gate. Left-handed sportsmen require separate coaching, and musicians suffer when conventions require them to learn their instruments with their weaker right hand playing a more principal role.
Studies show left-handers increasingly prone to mental illness such as schizophrenia, insomnia, depression, autism among many other pathological mental illnesses and ailments.[x] A British study revealed left-handers’ average lifespan 9 years shorter than their right-handed counterparts[xi]. In fact, historically (though less prevalent today) left-handers were stigmatized in various religions such as Islam and Christianity; considered to be of the devil and not on the ‘right’ side of God(where Jesus Christ and His favoured would sit)[xii]. In many European languages, terms referring to the ‘left’ being clumsy, crooked, ill-omened have been coined[xiii], stereotyping the left-hander as the lacking minority.
Applying the survival of the fittest theory[xiv] to the above logically suggests the extinction of the inferior left-hander through natural selection. Instead, we observe their prevalence in society; during the ice age 23% of handprints discovered were the right hand made by left-handers[xv], today despite medical advancement they still form a substantial minority. Perhaps the Left-handers’ secret to survival lies in their outstanding abilities in combat sports[xvi], perfect pitch abilities[xvii], top-notch IQ scores(Mc Manus)[xviii] and intrinsic artistic abilities, aptly described by William Hopkins(Emory University's Yerkes National Primate Research Center)-"The anomaly is left-handed people make up the extremely gifted and the extremely compromised…The rest of us make up the middle ground."
I would not change my child’s handedness as I believe there is no right or wrong dominant hand. Left-handed children already begin to show remarkable artistic talent and coming from a family where left-handers form the majority, I attest the beauty of being left-handed far outweighs the costs. Aside from the occasional struggle to mirror my right-handed mother and teachers’ demonstrations, I daresay I survive perfectly well doing what’s natural. Besides, left-handers are not all that handicapped once they train themselves to work right-handedly. For children, their first few years of development are crucial. Proper guidance and explanation help them overcome the differences, confusion and frustration when they discover they are the odd one in class, even embracing their handedness as there are many things left-handers can boast about.
[i] M. K. Holder. "Do Scientists Understand Why There are So Many More Right-Handers Than Left-Handers? Do Other Primates Show a Similar Tendency to Favor One Hand Over the Other?" Scientific American.Com. 18 Aug. 1997. 4 Oct. 2007 <http://www.sciam.com/askexpert_question.cfm?articleID=0005E039-6F37-1C72-9EB7809EC588F2D7>.
[ii] Freeman, Alex. "Left V Right, Assymmetrical Animals." BBC Wildlife May 2004. 4 Oct. 2007 <http://www.bbc.co.uk/nature/animals/features/341feature1.shtml>.
[iii] H. K. Holder. "Handedness and Brain Lateralization." 1995. Indiana University. 4 Oct. 2007 <http://www.indiana.edu/~primate/brain.html>.
[iv] "Left-Handedness: Does It Mean Anything?" Hypnotic World Psychology. 22 Sept. 2007. 25 Sept. 2007 <http://psychology.hypnoticworld.com/influence_personality/handedness.php>.
[v] "Science & Nature - Sex ID - Handedness." BBC.Co.UK. 3 Oct. 2007 <http://www.bbc.co.uk/science/humanbody/sex/articles/handedness.shtml>
[vi] Oxford University. "Gene for Left-Handedness Identified." Science Daily (2007). 1 Oct. 2007 <http://www.sciencedaily.com/releases/2007/08/070805141533.htm>
[vii] "Science: Older Mothers Have More Left-Handed Babies." New Scientist 1726 (1990). 4 Oct. 2007 <http://www.newscientist.com/article/mg12717262.800.html>.
[viii] "Geschwind-Galaburda Hypothesis." Wikipedia. 15 Aug. 2007. 4 Oct. 2007 <http://en.wikipedia.org/wiki/Geschwind-Galaburda_Hypothesis>.
[ix] "Handedness." Wikipedia. 2 Oct. 2007. 5 Oct. 2007 <http://en.wikipedia.org/wiki/Handedness>.
[x] Sarah Mogin. "The Oppression of Lefties." The Tartan Online (2006). 4 Oct. 2007 <http://www.thetartan.org/2006/2/27/pillbox/lefthand>
[xi] Simon Mays, and James Steele . New Findings on the Findings of Left-and-Right-Handedness in Medieaval Britain. Dept of Archaeology, University of Southampton and Ancient Monuments Lab, English Heritage. United Kingdom, 1995. 4 Oct. 2007 <http://web.archive.org/web/20021208040702/http://www.soton.ac.uk/~tjms/handed.html>.
[xii] "Left Handed Myths and Misunderstandings." Anything Left-Handed. 2000. 4 Oct. 2007 <http://www.anythingleft-handed.co.uk/lefty_myths.html>.
[xiii] Keith Milsom. "The Left Handers Newsletter – Nicknames." The Left-Handed Club Newsletter. 4 Oct. 2007. 4 Oct. 2007 <www.anythingleft-handed.co.uk>.
[xiv] Onion, Amanda. "The Left-Handed Advantage." ABC News. 17 Feb. 2005. 4 Oct. 2007 <http://abcnews.go.com/Technology/story?id=498707&page=1>.
[xv] Dr David Whitehouse. Left-Handedness Common in Ice Age. 2004. 4 Oct. 2007 <http://news.bbc.co.uk/2/hi/science/nature/3485967.stm>.
[xvi] Dr. Senol Dane. Is Left-Handedness a Neurological Advantage in Sportive Activities? Ataturk University, Turkey. 4 Oct. 2007 <http://coachesinfo.com/category/team_handball/258/>.
[xvii] Diana Deutsch. Pitch Memory: an Advantage for the Left-Handed. La Jolla: University of California, San Diego. 4 Oct. 2007 <http://www.philomel.com/pdf/Science-1978_199_559-560.pdf>.
[xviii] Onion, Amanda. "The Left-Handed Advantage." ABC News. 17 Feb. 2005. 4 Oct. 2007 <http://abcnews.go.com/Technology/story?id=498707&page=3>.