重心動揺における幾何学的な指標の物理学的意味 アルコール摂取時の解析

Abstract

In this paper, we report our development of an analytical index on stabilometry to diagnose a decrease in the cerebellar equilibrium function controlling vestibulo-spinal reflex. We measured the sway of the center-of-gravity of the body with a stabilometer for seven healthy men aged 19 to 26 years, and also recorded statokinesigrams after alcoholic intake. We propose classification of these statokinesigrams under two groups, statokinesigrams before the intake and after it. Suzuki et al. (1996) standardized indices, area of sway, total locus length and other parameters, on stabilometry, however, it was difficult to classify statokinesigrams with those indices. Here, we introduce a new index, sparse density, into stabilometry. We show that sparse density is a useful and stable index for classification in accordance with non-parametric statistics. Although we expected a similar effect on the circulatory system by the alcoholic load, variation of these indices was more complex than the variation derived from the organs for the recovery from the standpoint of time. We also analyzed data by paying attention to the force acting on them, which generated the statokinesigrams. We especially turned our attention to singular points where statistically tiny or huge forces are exerted. We could pursue the sparse density with sum of local force that acted on the center-of-gravity. We concluded that sparse density depends upon the function for the control of the center-of-gravity of the body.