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On-off intermittency in a human balancing task.

Juan L Cabrera·John G Milton
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Abstract

Motion analysis in three dimensions demonstrate that the fluctuations in the vertical displacement angle of a stick balanced at the fingertip obey a scaling law characteristic of on-off intermittency and that >98% of the corrective movements occur fast compared to the measured time delay. These experimental observations are reproduced by a model for an inverted pendulum with time-delayed feedback in which parametric noise forces a control parameter across a particular stability boundary. Our observations suggest that parametric noise is an essential, but up until now underemphasized, component of the neural control of balance.

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FeedbackHumansModels, NeurologicalNervous System Physiological PhenomenaNeuronsPostural BalanceJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

Juan L Cabrera, John G Milton. 2002-09-20. On-off intermittency in a human balancing task.. https://doi.org/10.1103/physrevlett.89.158702

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