The New Drawing on the Right Side of the Brain - Betty Edwards [29]
Try writing your signature in mirror writing.
A useful way to regard handedness is to recognize that hand preference is the most visible outward sign of how an individual’s brain is organized. There are other outward signs: eyedness (everyone has a dominant eye, used in sighting along an edge, for example) and footedness (the foot used to step off a curb or to start a dance step). The key reason for not forcing a child to use the nonpreferred hand is that brain organization is probably genetically determined, and forcing a change works against this natural organization. Natural preference is so strong that past efforts to change left-handers often resulted in ambidexterity: children capitulated to pressure (in the old days, even punishment) and learned to use the right hand for writing but continued to use the left for everything else.
Moreover, there is no acceptable reason for teachers or parents to force a change. Reasons proffered run from “Writing with the left hand looks so uncomfortable,” to “The world is set up for right-handers and my left-handed child would be at a disadvantage.” These are not good reasons, and I believe they often mask an inherent prejudice against left-handedness—a prejudice now rapidly disappearing, I’m happy to report.
Putting prejudice aside, there are important differences between left-handers and right-handers. Left-handers are generally less lateralized than right-handers. Lateralization means the degree to which specific functions are carried out almost exclusively by one hemisphere. For example, left-handers more frequently process language in both hemispheres and process spatial information in both hemispheres than do right-handers. Specifically, language is mediated in the left hemisphere in 90 percent of right-handers and 70 percent of left-handers. Of the remaining 10 percent of right-handers, about 2 percent have language located in the right brain, and about 8 percent mediate language in both hemispheres. Of the remaining 30 percent of left-handers, about 15 percent have language located in the right brain, and about 15 percent mediate language in both hemispheres. Note that individuals with right-hemisphere language location—termed right-hemisphere dominance, since language dominates—often write in the “hooked” position that seems to cause teachers so much dismay. Scientist Jerre Levy has proposed that hand position in writing is another outward sign of brain organization.
Do these differences matter? Individuals vary so much that generalizations are risky. Nevertheless, experts agree in general that a mixture of functions in both hemispheres (that is, a lesser degree of lateralization) creates the potential for conflict or interference. It is true that left-handers statistically are more prone to stutter and to experience the reading difficulty called dyslexia. However, other experts suggest that bilateral distribution of functions may produce superior mental abilities. Left-handers excel in mathematics, music, and chess. And the history of art certainly gives evidence of an advantage for left-handedness: Leonardo da Vinci, Michelangelo, and Raphael were all left-handed.
Former United States Vice President Nelson Rockefeller, a changed left-hander, had difficulty reading prepared speeches because of a tendency to read backward from right to left. The cause of this difficulty may have been his father’s unrelenting effort to change his son’s left-handedness.
“Around the family dinner table, the elder Mr. Rockefeller would put a rubber band around his son’s left wrist, tie a long string on it and jerk the string whenever Nelson started to eat with his left hand, the one he naturally favored.”
—Quoted in The Left-
Handers’ Handbook
by J. Bliss and J. Morella,
1980
Eventually, young Nelson capitulated and achieved a rather awkward ambidextrous compromise, but he suffered the consequences of his father’s rigidity throughout his lifetime.
Aztecs in early Mexico