People are divided into right-handed and left-handed. Most of us belong to the first group, and much less to the second group. Don't worry, even though you are more skilled with your left hand and foot, there is nothing wrong with you. But we recently got an answer to why such a division occurs.
Scientists from the University of Bochum last year research dealt with gene expression in the spinal cord between the eighth and twelfth week of pregnancy. They discovered that arm and leg movement it begins to design in the motor center in the cerebral cortex, which then sends signal to the spinal cord, which transforms the signal into movement.
At the beginning of human development, the motor center is not yet connected to the spinal cord, so the first signs of whether we will be left-handed or right-handed are noticeable. It is known that in the 13th week of pregnancy, babies already choose their finger for sucking - most choose the right, and some choose the left.
The researchers found that already at eight weeks of embryonic development there are differences in the formation of the spinal cord that affect it, which hand and foot we will be more skilled with. How exactly this happens will have to be investigated in more detail.
