A rigorous model of reflex function indicates that position and force feedback are flexibly tuned to position and force tasks

Mugge, W.; Abbink, D.A.; Schouten, A.C.; Dewald, J.P.A.; Van der Helm, F.C.T.

A rigorous model of reflex function indicates that position and force feedback are flexibly tuned to position and force tasks

Title

A rigorous model of reflex function indicates that position and force feedback are flexibly tuned to position and force tasks

Author

Mugge, W.
Abbink, D.A.
Schouten, A.C.
Dewald, J.P.A.
Van der Helm, F.C.T.

Faculty

Mechanical, Maritime and Materials Engineering

Department

Biomechanical Engineering

Date

2009-08-24

Abstract

This study aims to quantify the separate contributions of muscle force feedback, muscle spindle activity and co-contraction to the performance of voluntary tasks (‘‘reduce the influence of perturbations on maintained force or position’’). Most human motion control studies either isolate only one contributor, or assume that relevant reflexive feedback pathways during voluntary disturbance rejection tasks originate mainly from the muscle spindle. Human ankle-control experiments were performed, using three task instructions and three perturbation characteristics to evoke a wide range of responses to force perturbations. During position tasks, subjects (n = 10) resisted the perturbations, becoming more stiff than when being relaxed (i.e., the relax task). During force tasks, subjects were instructed to minimize force changes and actively gave way to imposed forces, thus becoming more compliant than during relax tasks. Subsequently, linear physiological models were fitted to the experimental data. Inhibitory, as well as excitatory force feedback, was needed to account for the full range of measured experimental behaviors. In conclusion, force feedback plays an important role in the studied motion control tasks (excitatory during position tasks and inhibitory during force tasks), implying that spindle-mediated feedback is not the only significant adaptive system that contributes to the maintenance of posture or force.

Subject

human motion control
neuromusculoskeletal modeling
afferent feedback
Golgi tendon organs
muscle spindles
muscle force feedback

To reference this document use:

http://resolver.tudelft.nl/uuid:28b9efe5-8650-476e-98e5-74991bb215df

Publisher

Springer

ISSN

0014-4819

Source

Experimental Brain Research, 2009

Part of collection

Institutional Repository