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Updated: Jul 17, 2026
08:12
Experimental Methods to Study Human Postural Control
Published on: September 11, 2019
Stochastic order parameter equation of isometric force production revealed by drift-diffusion estimates
T D Frank1, R Friedrich, P J Beek
1Institute for Theoretical Physics, University of Münster, Wilhelm-Klemm-Strasse 48149 Münster, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 7, 2007
Summary
Human motor control variability arises from both deterministic and random factors. Increased force output reduces stability and raises noise, revealing a structured control system.
Area of Science:
- Motor Control
- Dynamical Systems
- Human Physiology
Background:
- Understanding human motor control variability is crucial for neuroscience and rehabilitation.
- Identifying the underlying dynamical components (deterministic vs. random) is key.
Purpose of the Study:
- To determine the nature and structure of dynamical components contributing to motor control variability.
- To investigate how these components change with force output.
Main Methods:
- Derived a stochastic order parameter equation for isometric force production.
- Utilized drift-diffusion estimates from experimental data.
- Performed structural analysis of control components.
Main Results:
- Force variability increases with required force output due to decreased deterministic stability and increased noise intensity.
- Deterministic component comprises a linear control loop.
- Random component features a noise source that scales with force output.
Conclusions:
- Human isometric force production is characterized by a structured interplay of deterministic and random processes.
- A subject-independent noise level exists in human isometric force production.
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