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Updated: Jun 3, 2026
08:12
Experimental Methods to Study Human Postural Control
Published on: September 11, 2019
Transition from persistent to anti-persistent correlations in postural sway indicates velocity-based control.
Didier Delignières1, Kjerstin Torre, Pierre-Louis Bernard
1EA 2991 Movement To Health, Montpellier-1 University, Euromov, Montpellier, France. didier.delignieres@univ-montp1.fr
Plos Computational Biology
|March 11, 2011
Summary
Posture control during quiet stance is better explained by intermittent velocity limits rather than position dynamics. This finding challenges previous analyses of center-of-pressure (COP) movement, suggesting a new model for balance control.
Area of Science:
- Biomechanics
- Human postural control
- Dynamical systems analysis
Background:
- Traditional models of quiet stance focus on center-of-pressure (COP) position dynamics.
- Previous analyses using fractal methods have yielded varied conclusions regarding COP dynamics.
Purpose of the Study:
- To clarify methodological issues in analyzing COP dynamics.
- To re-evaluate the control mechanisms underlying quiet stance using advanced analytical techniques.
Main Methods:
- Methodological clarification of COP dynamics analysis.
- Application of stabilogram diffusion analysis, detrended fluctuation analysis, and improved spectral analysis.
- Development and testing of a bounded correlated random walk model for COP velocity.
Main Results:
- COP velocity during quiet stance is consistently bounded within specific limits.
- Evidence suggests intermittent velocity-based control is more relevant than position-based control.
- A novel model accurately reproduces key statistical features of experimental COP data.
Conclusions:
- The findings challenge the prevailing position-based control hypothesis for quiet stance.
- Intermittent velocity-based control offers a more relevant framework for understanding postural stability.
- The proposed bounded random walk model provides a robust explanation for observed COP dynamics.
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