Postural stability and fractal dynamics.

Methods of non-linear dynamics and deterministic chaos may provide us with effective quantitative descriptors of the dynamics of postural control. The goal of this study was to introduce a new measure, which would allow to determine the fractal structure of posturographic signals and to measure the effect of the loss of visual feedback information in postural control. The results of the study show that fractal dimension (Df) is a very useful, reliable and sensitive measure of the complexity of posturographic signals. Therefore Df can be used for the evaluation of postural stability and its changes due to pathology or an age-related decline.

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