直立維持における随意性の検討

抄録

Standing while making an effort to reduce postural sway (corrective standing, C-standing) was compared with natural standing (N-standing) to study the peculiarities of voluntary control in standing posture. Sway of the body center of gravity was recorded with eyes open and closed with both feet close together for 60 seconds using a stabilom-eter.
1) Whilcoxon-test was used to compare the results. In C-standing with eyes open, the area and the ratio of low frequency bands on power spectra and the kurtosis of amplitude histogram on the x-axis (right-left movement) increased and the length/area decreased.2) Patterns of statokinesigrams showed a non-specific type or a right-left enlargement type in C-standing with eyes open.3) Autocorrelograms of body sway showed a loss of periodicity on the x-axis in C-standing with eyes open.4) Attractors reconstructed from time series data obtained from the records showed a convergence of locus in the phase space on the x-axis in C-standing with eyes open.
Voluntary correction aimed at reducing the body sway in upright standing converted from rhythmic regular control (negative feedback control) depending on labyrinthine and proprioceptive reflexes to irregular adaptive control (positive feedback control) rely on visual information.