A Multifractal Dynamical Model of Human Gait

Bruce J. West; Nicola Scafetta

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arXiv · cond-mat/0504464

A Multifractal Dynamical Model of Human Gait

Bruce J. West·Nicola Scafetta

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Abstract

Summary: Walking is regulated through the motorcontrol system (MCS). The MCS consists of a network of neurons from the central nervous system (CNS) and the intraspinal nervous system (INS), which is capable of producing a syncopated output. The coupling of the latter two systems produces a complex stride interval time series that is characterized by fractal and multifractal properties that depend upon several biological and stress constraints. It has been shown that: (i) the gait phenomenon is essentially a rhythmic cycle that obeys particular phase symmetries in the synchronized movement of the limbs; (ii) the fractal and multifractal nature of the stride interval fluctuations become slightly more pronounced under faster or slower paced frequencies relative to the normal paced frequency of a subject; (iii) the randomness of the fluctuations increases if subjects are asked to synchronize their gait with the frequency of a metronome or if the subjects are elderly or suffering from neurodegenerative disease. Here we present a new model, called the super central pattern generator, able to reproduce these known properties of walking and discuss the physiological and psychological interpretations of the model parameters.

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Bruce J. West, Nicola Scafetta. 2005-04-19. A Multifractal Dynamical Model of Human Gait. https://arxiv.org/abs/cond-mat/0504464

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