Down Syndrome (DS), trisomy - 21, - is one of the most common chromosomal diseases. As a result, three copies of the 21st chromosome disrupt the functioning of the genes responsible for the formation and functioning of the brain, and therefore their carriers lag behind their peers in mental development from the very first days of life [3,6,12]. DS does not have any temporary, ethnic, or geographical differences between parents of the same age. In recent decades, there has been a significant increase in the occurrence of DS, an average of one case per 700 births [2,9]. The severity of neurological disorders in these children is not the same. Despite the widespread occurrence of this genetic abnormality, an insufficient number of works is devoted to the analysis of changes in the neurological status of such children; the mechanisms leading to cognitive deficit are not fully understood [1,5]. According to literature data, in DS there is a decrease in the density of nerve tissue, insufficient myelination, a decrease in the volume of cerebellar structures, immaturity and pathological activity of cortical neurons, impaired synthesis and functions of neurotransmitters [7, 10,11]. Hand-eye centers (parietal lobes) are better developed; therefore, training based on hand-eye perception (hand-eye) is the most successful in these children [2].

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