OBJECTIVE: To address the question of how the CNS generates muscle activation patterns for complex gestures, we have chosen to study a figure-eight movement. We hypothesized that the well defined rhythmic aspect of this figure will provide further insights into the temporal features of multi-muscular commands. METHODS: Subjects performed, as fast as possible, figure-eights initiated in the center of the figure with 4 different initial directions and 2 positions of the shoulder. We extracted the temporal modulation of the EMG patterns by calculating conjugate cross-correlation functions. RESULTS: (1) The muscular command was tuned with respect to the rotational direction of the figure-eight, (2) two sets of synergistic muscles acted in a reciprocal mode, and (3) these reciprocal commands presented an invariant temporal correlation with the spatial component of the velocity having the highest frequency. CONCLUSION: Our results suggest that the rhythmic features of certain drawing movements favor the partitioning of the muscles into synergistic groups acting in a reciprocal mode. The inclusion of an individual muscle in one group or the other takes into account the expected number of changes of direction in the movement as a whole. SIGNIFICANCE: Muscular temporal synergies may depend on the rhythmic features of the trajectory. Copyright 2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
OBJECTIVE: To address the question of how the CNS generates muscle activation patterns for complex gestures, we have chosen to study a figure-eight movement. We hypothesized that the well defined rhythmic aspect of this figure will provide further insights into the temporal features of multi-muscular commands. METHODS: Subjects performed, as fast as possible, figure-eights initiated in the center of the figure with 4 different initial directions and 2 positions of the shoulder. We extracted the temporal modulation of the EMG patterns by calculating conjugate cross-correlation functions. RESULTS: (1) The muscular command was tuned with respect to the rotational direction of the figure-eight, (2) two sets of synergistic muscles acted in a reciprocal mode, and (3) these reciprocal commands presented an invariant temporal correlation with the spatial component of the velocity having the highest frequency. CONCLUSION: Our results suggest that the rhythmic features of certain drawing movements favor the partitioning of the muscles into synergistic groups acting in a reciprocal mode. The inclusion of an individual muscle in one group or the other takes into account the expected number of changes of direction in the movement as a whole. SIGNIFICANCE: Muscular temporal synergies may depend on the rhythmic features of the trajectory. Copyright 2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
Authors: G Cheron; M Duvinage; C De Saedeleer; T Castermans; A Bengoetxea; M Petieau; K Seetharaman; T Hoellinger; B Dan; T Dutoit; F Sylos Labini; F Lacquaniti; Y Ivanenko Journal: Neural Plast Date: 2012-01-04 Impact factor: 3.599
Authors: Ana Bengoetxea; Françoise Leurs; Thomas Hoellinger; Ana M Cebolla; Bernard Dan; Joseph McIntyre; Guy Cheron Journal: Front Comput Neurosci Date: 2014-09-17 Impact factor: 2.380
Authors: Ana Bengoetxea; Françoise Leurs; Thomas Hoellinger; Ana Maria Cebolla; Bernard Dan; Guy Cheron; Joseph McIntyre Journal: Front Comput Neurosci Date: 2015-01-09 Impact factor: 2.380