The choice of an active hand speaks a lot about the organization of the brain. Left half of our brain manages the right side of the body, and vice versa. At the same time, the hemisphere of the brain is not quite equal - part of the mental functions is clearly controlled from the right hemisphere, and the other part is from the left. This connection of functions with hemispheres is called lateralization.
Children choose the "favorite" hand at about the same when they start to speak freely - about 4 years. Levorhood or rights - a steady characteristic and, as a rule, it no longer changes throughout life.
For most people, the dominant hemisphere is left. There is a Command Center for Speech, and the same area that manages the ability to pronounce words, manages and shallow motility. 90% of people write and more actively gesticulate with their right hand.
Evolutionary psychologists think that such a neighborhood is not accidental - most likely, we "told" gestures. Then we became smarter, learned to use all sorts of guns like sticks and cobblestones, and we needed hands to work, so I had to learn to talk to talk.
The ability to express his thoughts with the help of gestures - from these consecutive movements, then the syntactic structure of the language was then turned out.
This theory is confirmed by the fact that children who have not been developed by small motility begin to speak later peers.
Left, right or no difference?
In the early 20th century it was believed that left-handed the anomaly of the development, which could lead to almost mental diseases. At that time (and a lot later), the left-handed children "retired" to make them write with their right hand.
Today it is clear to us that the left-hand activities and the rights are not a choice of two options, but a scale, at one end of which is the absolute right-handers, and on the other - left-handers. In the middle, people who successfully use both hands.
Simple tasks - for example, scratch or take a circle from the table - you can do any hand. However, more complex, such as a letter, require specialized possibilities of the left hemisphere. Therefore, most children write and paint with their right hand. However, the skill of using a certain hand is developing gradually, and the brain is also gradually adapted to this selection.
Scientists believe that children who use only one hand, very strong brain lateralization.
The ambidexters are the children who are equally well painted and write and left, and their right hand, differ in the atypical development of language and motor centers. The percentage of ambidexters is small - only 3-4%, however, among children with an autistic spectrum disorders, it is much higher and comes to 47%. Perhaps this will help diagnose autism in the early stages of the child's development.
Well, what of this benefit?
Now autism is diagnosed relatively late when problems with speech are starting. However, the brain of a small child is extremely flexible and susceptible to therapy, and earlier the beginning of the treatment of autism can give stunning results. The fact that the child uses both hands equally, can be the first call, which is important not to miss.
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