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Updated: Nov 3, 2025
08:12
Experimental Methods to Study Human Postural Control
Published on: September 11, 2019
9.8K
Response to perturbation during quiet standing resembles delayed state feedback optimized for performance and
Ambrus Zelei1,2, John Milton3, Gabor Stepan1,4
1MTA-BME Research Group on Dynamics of Machines and Vehicles, Budapest, 1111, Hungary.
Scientific Reports
|June 1, 2021
Summary
Human postural sway, the body's balance control, is modeled as a critically damped oscillator. This feedback mechanism optimizes for speed and robustness against sensory disturbances.
Area of Science:
- Biomechanics
- Human motor control
- Systems neuroscience
Background:
- Postural sway arises from complex sensory-neural-muscular feedback loops.
- Modeling postural control is challenging due to the complex and potentially chaotic nature of oscillations.
- Analyzing responses to large perturbations is key to understanding underlying control mechanisms.
Purpose of the Study:
- To analyze human postural response to large perturbations during quiet standing.
- To model recovery dynamics using an inverted pendulum with delayed state feedback.
- To test hypotheses regarding the optimization of postural control gains.
Main Methods:
- Measurements of postural responses to significant perturbations.
- Modeling recovery dynamics with an inverted pendulum and delayed feedback.
- Parameter fitting to compare experimental data with theoretical models.
Main Results:
- Postural recovery dynamics closely resemble a critically damped oscillator.
- Hypotheses H1 (critical damping) and H3 (performance-robustness optimization) were supported.
- Hypothesis H2 (fastest possible response) was rejected.
Conclusions:
- Human postural balance control to large perturbations aligns with a delayed feedback mechanism.
- The control strategy is optimized for a balance between response speed and robustness to sensory perturbations.
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