Left-handed, right-handed, is the common name of [left-handed] [right-handed].
Every time Dr. Clove hears such a dialogue on the edge, he will unconsciously hold his glasses with his left hand and struggle with whether to insert a mouth in the past.
Left-handed, who has always accounted for only about 10% of the earth’s people, has always been a minority. There are always urban legends about minority groups in the Jianghu…
Left-handed only left-handed work is good?
Of course not.
On the other hand, right-handed work is not only good for right-handed work.
Many people are purely right-handed and are more accustomed to using their right hand no matter they are what.
There are also many people who are not pure left-handed or right-handed, but have a relative [habitual hand]. The amount and degree of work that the left and right hands are good at are not the same respectively. For example, writing is used to using the right hand, scissors are used to using the left hand, playing basketball is used to making layups with the left hand…
There are still very few people who can do all kinds of things from left to right, even drawing their bows from left to right and fighting with each other from left to right.
Left handedness is innate?
The heritability of left-handed is about 25%.
When the fetus is still in the mother’s belly, the behavior of “eating hands and hands” can already show habitual hands.
Fetuses sucking the right thumb are also right-handed when they grow up, while 2/3 of those sucking the left thumb are also left-handed when they grow up, which is determined by genes and maternal environment.
Heredity has an impact on habitual hands, but it is not the most important factor. Culture and environment will also have an impact … and it is also very large.
The left-hander dies early, and the right-hander lives longer?
The influence of culture and environment lies in the fact that in the past, left-handedness was not accepted by the society, and many left-handedness was corrected into right-handedness by rigid teachers or traditional parents.
As a result, many previous research conclusions on left-handedness are actually wrong.
For example, some people once thought that right-handed people lived longer, while more recent population surveys found that:
On the whole, habitual hands have nothing to do with life span, although left-handed hands are indeed more likely to die from accidents and wars.
Left-handedness is more prone to schizophrenia?
For a long time, people thought that left-handedness was more likely to develop schizophrenia, because the proportion of left-handedness in schizophrenic patients was higher than that in normal people.
But this is wrong. The fact is:
The prevalence rate of schizophrenia in men is higher, while the number of left-handed men is also higher, but there is no causal correlation between the two.
Left-handed is smarter and better?
There are indeed famous left-handedness in science, music, politics and other fields, but these examples cannot be used as evidence that left-handedness is better. We can always list more outstanding right-handedness.
In the whole population, intelligence performance has nothing to do with left/right hand preference.
However, left-handed or mixed-handed people perform faster in fast switching attention tasks, and they will feel that time passes faster!
Another point is that most people in the society are right-handed, and many living utensils and environments are designed for right-handed people. Left-handed people will face more difficulties and inconveniences in daily life.
Perhaps, this really forces the left-handedness to have more creative thinking to solve the difficulties, otherwise… the fittest will be eliminated.
And like [you are left-handed, you must be very smart! ] This kind of chat opening remarks may only bring out the embarrassment of the whole scene.
Training left and right hands can develop the brain?
If your goal is to use your hands skillfully, such as playing the piano, you should really train your hands.
If you train to brush your teeth with your left hand, the benefits will be … the hygiene of your right tooth may be better. Because the usual hand will brush the other side more carefully first, and then you will be lazy when brushing.
At present, there is no evidence that training non-habitual hands has special benefits for what.
Only people have left hands?
Humans are not special.
Primates such as gorillas have varying degrees of preference for left or right hands. Kangaroos… are almost all left-handed.