Characteristics of Autocorrelation Structure of Lower Extremity Functional Laterality in Disturbed and Undisturbed Bipedal Upright Stance

摘要

Purpose. It is posited that functional laterality is influenced by the generation and conduction of neural signals and therefore associated with sensorimotor control. The question arises if symmetry or asymmetry in sensorimotor processing affects the development of symmetric or asymmetric motor programs in the lower extremities. The purpose of the study was to examine the mechanisms of the human mobility moto-control - the process of maintaining body balance in a standing position through an appropriate course of distribution of ground reaction forces in a time frame, in a situation requiring lower extremity movement symmetry. Methods. The autocorrelation function was calculated for ground reaction forces (in the three orthogonal axes) registered during 45 s of bipedal upright stance in two conditions (eyes open and closed). Results. Minor albeit significant deficiencies in postural muscle control were revealed as a function of time, as evidenced in the decay of the autocorrelation function to zero (T₀) between the right and left foot for the mediolateral ground reaction force signal. However, the results attest to symmetrical sensorimotor control between both feet. Conclusions. Motor actions (postural corrections) performed in long-duration tasks may have less of an effect on sensorimotor control than those applied in shorter duration projections. ANOVA and correlation analysis (across all variables) of the right and left foot T₀ indicate considerable symmetry in the control of force magnitude and direction during upright standing.