Analysis of the graphomotor activity of the subdominant hand under unimanual and bimanual conditions

Abstract

The graphic activity (drawing circles) of the left hand was compared under the bimanual condition with the motor activity of the same hand, but under the unimanual condition. The study involved 20 healthy psychology students (mean age = 20 years). The comparative analysis of the unimanual and bimanual graphomotor movements of the left hand showed differences in the speed, execution time and size of the drawn figures. The analysis of dynamics of the motor activity of the left hand under both conditions in sequence showed significant changes for the bimanual condition based on the main kinematic indicators, which was not identified for a unimanual condition. Thus, the bimanual coordination is assumed to be irreducible to the sum of the coordination of two unimanual movements.