Front. Physiol. Frontiers in Physiology Front. Physiol. 1664-042X Frontiers Media S.A. 10.3389/fphys.2018.01566 Physiology Correction Corrigendum: Frequency-Specific Fractal Analysis of Postural Control Accounts for Control Strategies Gilfriche Pierre 1 2 * Deschodt-Arsac Véronique 2 Blons Estelle 2 Arsac Laurent M. 2 1CATIE - Centre Aquitain des Technologies de l'Information et Electroniques, Talence, France 2Univ. Bordeaux, CNRS, Laboratoire IMS, UMR 5218, Talence, France

Edited and reviewed by: Zbigniew R. Struzik, The University of Tokyo, Japan

 *Correspondence: Pierre Gilfriche pierre.gilfriche@u-bordeaux.fr

This article was submitted to Fractal Physiology, a section of the journal

 02 11 2018 2018 9 1566 14 08 2018 18 10 2018 Copyright © 2018 Gilfriche, Deschodt-Arsac, Blons and Arsac. 2018 Gilfriche, Deschodt-Arsac, Blons and Arsac

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 A Corrigendum on Frequency-Specific Fractal Analysis of Postural Control Accounts for Control Strategies by Gilfriche, P., Deschodt-Arsac, V., Blons, E., and Arsac, L. M. (2018) Front. Physiol. 9:293. doi: 10.3389/fphys.2018.00293 postural control center-of-pressure fractal physiology DFA FsFA 1/f scaling

In the original article, there was an error. In the Discussion, we analyze how the scaling exponents computed on the differentiated signal and the original signal can be used to describe the frequency content of the signal in a global model. When differentiating the signal, we supposed that the value of β increased by 2, however, as β is the opposite of the slope in the power spectral density, the value of β decreased by 2 when the signal is differentiated. Thus, the equations β1 = 2 × α1 +1 and β1 = (2 × α1−1)+2 are incorrect and should be replaced by: β1 = 2 × α1−3 and β1 = (2 × α1−1)−2.

A correction has been made to Discussion, Interpretations and confrontation with other theories, paragraph two:

Indeed, Figure 7 shows that the whole frequency content of the CoP velocity signal could then be described by four parameters:

Pf0 (or AAMV)

β1, the opposite of the slope of the low-frequency antipersistent range, with β1=2×α1-3

α1 being here the frequency-specific fractal exponent associated with visuo-vestibular loops (low-frequencies) in CoP position. This result is obtained by the fact that β1 is computed from the CoP velocity while α1 is computed from CoP position, its integral, so more precisely: β1 = (2 × α1−1)−2.

β2, the opposite of the slope of the high-frequency persistent range, with β2=2×α2-1

α2 being here the frequency-specific fractal exponent associated with proprioceptive loops (high-frequencies) in CoP velocity.

f0, the crossover frequency, which might be variable from one individual to another but is likely between 0.5 and 2 Hz according to the literature.

The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. The original article has been updated.

Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.