Left-handedness: Does it mean anything? - Psychologist World
More Left-handedness Information
Environmental theories on left handedness
Birth stress
Left-handed people cringe at this theory, because its basic premise is that
left-handedness is due to brain damage during the birth process. Unfortunately,
some statistics do back this theory up.
Difficult or stressful births happen far more commonly among babies who grow
up to be left-handed or ambidextrous. Birth stress is also associated with a
number of birth defects and complications, including cerebral palsy and autism.
But there are objections; you can breathe easy now:
Throughout history and throughout the world, the level of medicine and technology
to assist with childbirth has improved. In spite of that, the proportion of
left-handed people has not decreased. (In a sense, it has increased because
more people see left-handedness as the benign trait it is.)
It does not explain why humans are right-handed by default, with only birth
stress making them left-handed. It could, however, explain left-handedness
in combination with some of the other theories presented here.
Parental pressure
This theory explains right-handed dominance by claiming that since the parents
who raised us are mostly right-handed, we came to be mostly right-handed and
so on.
Objections:
It does not explain how right-handed dominance started in the first place.
The handedness of children is more closely related to their biological parents
than to adoptive parents.
It does not explain why left-handedness has persisted for so long.
Social stigma and repression of left-handedness
Throughout history being left-handed was considered as negative - the Latin
word sinister meant "left". Hence the many negative connotations associated
with the word "left-handed": clumsy, awkward, unlucky, insincere,
sinister, malicious, and so on. There have been, however, many famous left-handed
people, and the associated right brain hemisphere that is said to be more active
in left-handed people, has been found in some circumstances to be associated
with genius and is correlated with artistic and visual skill.
Until very recently in Taiwan, left-handed people were strongly encouraged
to switch to being right-handed (or at least, switch to writing with the right
hand). It is more difficult to write legible Chinese characters with the left
hand than it is to write Latin letters. Remember that "easy" and "difficult"
depend on the person using those terms, so your writing may be neater. Because
it is supposedly easier to write when moving your hand towards its side of the
body, it is easier to write the Roman alphabet with your right hand than with
your left. Conversly, Arabic and Hebrew, which go from right to left, would
be easier to write with the left hand. Again, "easier" and "harder"
are subjective.
It is possible that sun worship relates to the association of the left with
evil. People in the northern hemisphere, looking south, would see the sun rise
on their left, move rightwards across the sky, and set on their right. In the
southern hemisphere the opposite happens. Among cultures from the southern hemisphere,
right-handedness is still dominant. No study on left-side connotations from
those cultures has been done.
However, since most sun-worshipping cultures see the setting sun as it dying
or vanishing, the right side would indicate the negative associations associated
with a setting sun. This is the opposite trend from that.
Left-sidedness
In humans
Studies show that left-handedness does not necessarily correspond with "left-sidedness"
(using your left foot to kick with, for example). The same thing holds with
"eyedness."
In animals
Most primates also exhibit a preference for using one hand over the other although
their populations are not right-hand preferential.
