JulieW8
2004-02-04 15:05:10 UTC
My SIL gave me a book one Christmas called "Lefties: the origins and
consequences of being left-handed," by Jack Fincher." It's a much more
serious look at things than I usually read (which is why I hadn't read
it) but I ran out of things to read in the bathroom. <G>
I hadn't realized how complicated the issue was until I read this
book.
In one survey of the supposedly easy question of which hand they were
better with, the subjects were wrong in a quarter to half the cases
when they were tested. One psychologist defines handedness in terms of
the hand preferred in learning new tasks. Another defines it in terms
of the one that excels in fine and precise movements, such as
threading a needle. Still others define it in terms of relative
strength and dexterity of the two hands. Almost none of them agree on
how to phrase a questionnaire to winnow out crucial distinctions. For
example, questions neglect untaught tasks such as which hand you use
to brush your teeth or strike a match. They also don't take into
consideration the selection of tasks, cultural differences and learned
skills, such as right-handed man who deals cards left-handed because
that's how he learned from his father. One pair of researchers found
the more direct the investigation, the more numerous the tests and the
less they concern learned movements, the larger the proportion of left
handedness.
And most people, righties and lefties, switch hands for different
tasks and display varying degrees of ambidexterity. One group of
researchers were frustrated by what they saw as a number of subjects
whose right- and left-sidedness was confused.
One test seems to be most decisive. Called the Torque Test, it is
performed on children and has the child draw some X's, circle them and
then sign their name with first one hand and then the other. The
strength and control in handwriting indicates preferred hand, but the
drawing of the circles indicates something else: the brain
organization underlying the natural tendency before the onset of
socialization. The child may do many or most things with the right
hand, yet be a left-hander at heart. Right-handers consistently draw
their circles counterclockwise, left-handers tend to draw them
clockwise.
The kind of task in testing handedness is also crucial. In one study,
depending on which of three measures were used to make the
identification, the percentage of left-handers ranged from 2% to 35%!
A motor task as simple as flexing a single finger can throw the
statistician into quandary. Right-handers are better at it - but with
their left hand. One researcher found in testing one group of students
that 20% were left-handed, while in another comparable group he found
none. And it gets worse - in a test of 57 children between the ages of
5-1/2 and 13, another researcher found left-hand superiority in 16 of
them. A year later he went back - and found it in only one.
So I continue to write lefty, kick righty, play baseball
ambidextrously and shoot pool ambilaterally!
consequences of being left-handed," by Jack Fincher." It's a much more
serious look at things than I usually read (which is why I hadn't read
it) but I ran out of things to read in the bathroom. <G>
I hadn't realized how complicated the issue was until I read this
book.
In one survey of the supposedly easy question of which hand they were
better with, the subjects were wrong in a quarter to half the cases
when they were tested. One psychologist defines handedness in terms of
the hand preferred in learning new tasks. Another defines it in terms
of the one that excels in fine and precise movements, such as
threading a needle. Still others define it in terms of relative
strength and dexterity of the two hands. Almost none of them agree on
how to phrase a questionnaire to winnow out crucial distinctions. For
example, questions neglect untaught tasks such as which hand you use
to brush your teeth or strike a match. They also don't take into
consideration the selection of tasks, cultural differences and learned
skills, such as right-handed man who deals cards left-handed because
that's how he learned from his father. One pair of researchers found
the more direct the investigation, the more numerous the tests and the
less they concern learned movements, the larger the proportion of left
handedness.
And most people, righties and lefties, switch hands for different
tasks and display varying degrees of ambidexterity. One group of
researchers were frustrated by what they saw as a number of subjects
whose right- and left-sidedness was confused.
One test seems to be most decisive. Called the Torque Test, it is
performed on children and has the child draw some X's, circle them and
then sign their name with first one hand and then the other. The
strength and control in handwriting indicates preferred hand, but the
drawing of the circles indicates something else: the brain
organization underlying the natural tendency before the onset of
socialization. The child may do many or most things with the right
hand, yet be a left-hander at heart. Right-handers consistently draw
their circles counterclockwise, left-handers tend to draw them
clockwise.
The kind of task in testing handedness is also crucial. In one study,
depending on which of three measures were used to make the
identification, the percentage of left-handers ranged from 2% to 35%!
A motor task as simple as flexing a single finger can throw the
statistician into quandary. Right-handers are better at it - but with
their left hand. One researcher found in testing one group of students
that 20% were left-handed, while in another comparable group he found
none. And it gets worse - in a test of 57 children between the ages of
5-1/2 and 13, another researcher found left-hand superiority in 16 of
them. A year later he went back - and found it in only one.
So I continue to write lefty, kick righty, play baseball
ambidextrously and shoot pool ambilaterally!