Annotation

A study of two phases (introduction and intermediate control) of bimanual graphomotor activity was conducted. The hypothesis is that the initial (introductive) and executive phases of a bimanual movement differ in manual preference, and the sign of this difference depends on the content of the motor task, which is determined by the level of movement construction (according to N. A. Bernstein). The hypothesis was confirmed by experiment in which subjects performed bimanual movements, simultaneously drawing contours of various configurations on two tablets. Tasks specific to each leading level of construction were selected: graphomotor test (B), tracing a square along a dotted contour (C1), drawing a square by memory (C2), drawing a house (D), writing the word “dad” («папа» in Russian) in block letters (E). Frequency analysis of manual preference was carried out. It has been established that in most cases the introduction begins with the left hand (except for level D), and the execution continues with the right. However, even within the executive stage, the leading hand can change. This does not match with the data that sign of synchronization (which hand should be the leading one) is determined and does not change during the executive phase of the movement.