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Medical & Biological Engineering & Computing

, Volume 50, Issue 9, pp 917–923 | Cite as

Neural oscillators triggered by loading and hip orientation can generate activation patterns at the ankle during walking in humans

  • Sook-Yee Chong
  • Heiko Wagner
  • Arne Wulf
Original Article

Abstract

Spinal pattern generators (SPGs), which are neural networks without a central input from the brain may be responsible for controlling locomotion. In this study, we used neural oscillators to examine the rhythmic patterns generated at the ankle during walking. Seven healthy male subjects were requested to walk at their normal self-selected speed on a treadmill. Force measurements acquired from pressure insoles, electromyography and kinematic data were captured simultaneously. The SPG model consisted of a simple oscillator made up of two neurons; one neuron will activate an ankle extensor and the other will activate an ankle flexor. The outputs of the oscillator represented the muscle activation of each muscle. A nonlinear least squares algorithm was used to determine a set of parameters that would optimise the differences between model output and experimental data. Insole forces and hip angles of six consecutive strides were used as inputs to the model, which generated outputs that closely fitted experimental data. Our results showed that it is possible to reproduce muscle activations using neural oscillators. A close correlation between simulated and measured muscle activations indicated that spinal control should not be underestimated in models of human locomotion.

Keywords

Locomotion Spinal pattern generators EMG Neural networks 

Notes

Acknowledgments

This study was supported by the German Federal Ministry of Education and Research (BMBF), project no. 01EC1003A. The authors would like to thank Hanno Focke and David Schinowski for their technical assistance, and Thomas Wulf, Kim Bostroem and Thomas Stief for helpful comments and suggestions.

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Copyright information

© International Federation for Medical and Biological Engineering 2012

Authors and Affiliations

  1. 1.Bewegungswissenschaft, Motion ScienceWestfaelische Wilhelms-Universität MünsterMünsterGermany

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