Relating reflex gain modulation in posture control to underlying neural network properties using a
Jasper Schuurmans1, Frans C T van der Helm, Alfred C Schouten
1Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD, Delft, The Netherlands. j.schuurmans@tudelft.nl
Journal of Computational Neuroscience
|September 25, 2010
Summary
Humans adapt reflex gains for posture control. This study reveals how neural and sensory mechanisms directly influence reflex gains, impacting joint dynamics and experimental identifiability.
Area of Science:
- Neuroscience
- Biomechanics
- Systems Biology
Background:
- Reflexive feedback is crucial for human posture control, enabling compensation for mechanical disturbances.
- Reflex modulation, quantified by reflex gains, can be influenced by neural mechanisms like presynaptic inhibition and fusimotor drive.
- Understanding the link between neural substrates and reflex gains is essential for interpreting experimental findings.
Purpose of the Study:
- To investigate the influence of underlying neural and sensory mechanisms on mechanical joint behavior during posture control.
- To determine how specific neural, sensory, and synaptic parameters affect joint dynamics and reflex gains.
Main Methods:
- Development of a detailed neuromusculoskeletal model simulating a limb controlled by spiking neurons.
- Application of force perturbations to the limb model, mimicking experimental conditions.
- Utilized system identification to quantify reflex gains and performed sensitivity analysis on model parameters.
Main Results:
- Velocity, position, and force reflex gains showed positive correlations with their primary neural substrates (Ia, II, and Ib afferents, respectively).
- Position and force feedback gains exhibited significant interactions with other neural and sensory properties.
- Demonstrated direct relationships between specific neural parameters and quantified reflex gains.
Conclusions:
- Neural properties significantly impact joint dynamics, providing insights into reflex gain identifiability in experimental settings.
- The study highlights the complex interplay between neural substrates and reflex control during posture.
- Findings contribute to a deeper understanding of sensorimotor control and reflex modulation.
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