Walking dynamics are symmetric (enough)

M. Mert Ankarali, Shahin Sefati, Manu S. Madhav, Andrew Long, Amy J Bastian, Noah J. Cowan

Research output: Contribution to journalArticle

Abstract

Many biological phenomena such as locomotion, circadian cycles and breathing are rhythmic in nature and can be modelled as rhythmic dynamical systems. Dynamical systems modelling often involves neglecting certain characteristics of a physical system as a modelling convenience. For example, human locomotion is frequently treated as symmetric about the sagittal plane. In this work, we test this assumption by examining human walking dynamics around the steady state (limit-cycle). Here,we adapt statistical cross-validation in order to examine whether there are statistically significant asymmetries and, even if so, test the consequences of assuming bilateral symmetry anyway. Indeed, we identify significant asymmetries in the dynamics of human walking, but nevertheless show that ignoring these asymmetries results in a more consistent and predictive model. In general, neglecting evident characteristics of a system can be more than a modelling convenience-it can produce a better model.

Original languageEnglish (US)
Article number0209
JournalJournal of the Royal Society Interface
Volume12
Issue number108
DOIs
StatePublished - Jul 6 2015

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Walking
Dynamical systems
Locomotion
Biological Phenomena
Respiration

Keywords

  • Cross-validation
  • Locomotion
  • Rhythmic dynamics
  • Symmetry

ASJC Scopus subject areas

  • Biophysics
  • Biotechnology
  • Bioengineering
  • Biomedical Engineering
  • Biomaterials
  • Biochemistry

Cite this

Ankarali, M. M., Sefati, S., Madhav, M. S., Long, A., Bastian, A. J., & Cowan, N. J. (2015). Walking dynamics are symmetric (enough). Journal of the Royal Society Interface, 12(108), [0209]. https://doi.org/10.1098/rsif.2015.0209

Walking dynamics are symmetric (enough). / Ankarali, M. Mert; Sefati, Shahin; Madhav, Manu S.; Long, Andrew; Bastian, Amy J; Cowan, Noah J.

In: Journal of the Royal Society Interface, Vol. 12, No. 108, 0209, 06.07.2015.

Research output: Contribution to journalArticle

Ankarali, MM, Sefati, S, Madhav, MS, Long, A, Bastian, AJ & Cowan, NJ 2015, 'Walking dynamics are symmetric (enough)', Journal of the Royal Society Interface, vol. 12, no. 108, 0209. https://doi.org/10.1098/rsif.2015.0209
Ankarali, M. Mert ; Sefati, Shahin ; Madhav, Manu S. ; Long, Andrew ; Bastian, Amy J ; Cowan, Noah J. / Walking dynamics are symmetric (enough). In: Journal of the Royal Society Interface. 2015 ; Vol. 12, No. 108.
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