Why a pediatrician needs to know about the neurophysiological mechanisms underlying left-sidedness and left-handedness in children

Left-sidedness is a characteristic of individual typological features of a person. Left-handedness can be considered as a clear marker of functional brain asymmetry, which determines the specificity of the cognitive features of a child. Archaeological evidence confirms the existence of left-handedness among early ancestors, predating modern humans and living over a million years ago. This suggests that the left-handedness, as a marker of asymmetry, persists at a certain level due to evolutionary mechanisms, which contributes to the stability and adaptability of the species. Historical data indicate a high left-handedness stigma degree ingrained in people’s heads. Fundamental scientific research allowed us to do away with an evil practice of “correcting” left-handed children. The awakened scientific interest in neurophysiology has spurred the development of numerous hypotheses and theories to explain the phenomenon of left-handedness. However, there is no single generally accepted theory of this phenomenon. According to modern concepts, left-handedness is considered a manifestation of functional asymmetry in the brain performance. Asymmetry is a phenomenon that is observed at various levels and has certain forms of expression. In the prenatal period, the ontogenesis of the brain reveals a number of functional and anatomical asymmetries, which reflects the dynamic, multifaceted process of brain lateralization. The article discusses possible causes of left-handedness with an emphasis on the method of assessing a child’s hand dominance. The discovery of the phenomenon of lateralization is a major step towards understanding the mental characteristics and cognitive functions of children. The concept of these aspects of development underlies the individual approach both in pedagogical activity and in the context of interactions between pediatricians, patients, and their parents.

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