| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
The Journal of Neurophysiology Vol. 85 No. 2 February 2001, pp. 605-619
Copyright ©2001 by the American Physiological Society
Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
Saltiel, Philippe,
Kuno Wyler-Duda,
Andrea D'Avella,
Matthew C. Tresch, and
Emilio Bizzi.
Muscle Synergies Encoded Within the Spinal Cord: Evidence From
Focal Intraspinal NMDA Iontophoresis in the Frog. J. Neurophysiol. 85: 605-619, 2001. This paper relates
to the problem of the existence of muscle synergies, that is whether
the CNS command to muscles is simplified by controlling their activity
in subgroups or synergies, rather than individually. We approach this
problem with two methods that have been recently introduced:
intraspinal N-methyl-D-aspartate (NMDA)
microstimulation and a synergy-extracting algorithm. To search for a
common set of synergies encoded for by the spinal cord whose
combinations would account for a large range of electromyographic (EMG)
patterns, we chose, rather than examining a large range of natural
behaviors, to chemically microstimulate a large number of spinal cord
interneuronal sites in different frogs. A possible advantage of this
complementary method is that it is task-independent. Visual inspection
suggested that the NMDA-elicited EMG patterns recorded from 12 leg
muscles might indeed be constructed from smaller subgroups of muscles
whose activity co-varied, suggestive of synergies. We used a
modification of our extracting computational algorithm whereby a
nonnegative least-squares method was employed to iteratively update
both the synergies and their coefficients of activation in
reconstructing the EMG patterns. Using this algorithm, a limited set of
seven synergies was found whose linear combinations accounted for more
than 91% of the variance in the pooled EMG data from 10 frogs, and
more than 96% in individual frogs. The extracted synergies were
similar among frogs. Further, preferred combinations of these synergies
were clearly identified. This was found by extracting smaller sets of
four, five, or six synergies and fitting each synergy from those sets
as a combination from the set of seven synergies extracted from the
same frog; the synergy combinations from each frog were then pooled
together to examine their frequency of occurrence. Concordance with
this method of identifying synergy combinations was found by examining
how the synergies from the set of seven correlated pair-wise as they
reconstructed the EMG data. These results support the existence of
muscle synergies encoded within the spinal cord, which through
preferred combinations, account for a large repertoire of spinal cord
motor output. These findings are contrasted with previous approaches to
the problem of synergies.
This article has been cited by other articles:
|
|
 |
|
  V. C. K. Cheung, A. d'Avella, and E. Bizzi Adjustments of Motor Pattern for Load Compensation Via Modulated Activations of Muscle Synergies During Natural Behaviors J Neurophysiol, March 1, 2009; 101(3): 1235 - 1257. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. J. Kutch, A. D. Kuo, A. M. Bloch, and W. Z. Rymer Endpoint Force Fluctuations Reveal Flexible Rather Than Synergistic Patterns of Muscle Cooperation J Neurophysiol, November 1, 2008; 100(5): 2455 - 2471. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. d'Avella, L. Fernandez, A. Portone, and F. Lacquaniti Modulation of Phasic and Tonic Muscle Synergies With Reaching Direction and Speed J Neurophysiol, September 1, 2008; 100(3): 1433 - 1454. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Drew, J. Kalaska, and N. Krouchev Muscle synergies during locomotion in the cat: a model for motor cortex control J. Physiol., March 1, 2008; 586(5): 1239 - 1245. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. A. Overduin, A. d'Avella, J. Roh, and E. Bizzi Modulation of Muscle Synergy Recruitment in Primate Grasping J. Neurosci., January 23, 2008; 28(4): 880 - 892. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Torres-Oviedo and L. H. Ting Muscle Synergies Characterizing Human Postural Responses J Neurophysiol, October 1, 2007; 98(4): 2144 - 2156. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. G. Larson and J. T. Stern Jr Humeral retractor EMG during quadrupedal walking in primates J. Exp. Biol., April 1, 2007; 210(7): 1204 - 1215. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. D. Klein Breteler, K. J. Simura, and M. Flanders Timing of Muscle Activation in a Hand Movement Sequence Cereb Cortex, April 1, 2007; 17(4): 803 - 815. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. A. Gaunt, A. Prochazka, V. K. Mushahwar, L. Guevremont, and P. H. Ellaway Intraspinal Microstimulation Excites Multisegmental Sensory Afferents at Lower Stimulus Levels Than Local {alpha}-Motoneuron Responses J Neurophysiol, December 1, 2006; 96(6): 2995 - 3005. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. A. Daley and A. A. Biewener Running over rough terrain reveals limb control for intrinsic stability PNAS, October 17, 2006; 103(42): 15681 - 15686. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Krouchev, J. F. Kalaska, and T. Drew Sequential Activation of Muscle Synergies During Locomotion in the Intact Cat as Revealed by Cluster Analysis and Direct Decomposition J Neurophysiol, October 1, 2006; 96(4): 1991 - 2010. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Torres-Oviedo, J. M. Macpherson, and L. H. Ting Muscle Synergy Organization Is Robust Across a Variety of Postural Perturbations J Neurophysiol, September 1, 2006; 96(3): 1530 - 1546. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. d'Avella, A. Portone, L. Fernandez, and F. Lacquaniti Control of fast-reaching movements by muscle synergy combinations. J. Neurosci., July 26, 2006; 26(30): 7791 - 7810. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. C. Tresch, V. C. K. Cheung, and A. d'Avella Matrix Factorization Algorithms for the Identification of Muscle Synergies: Evaluation on Simulated and Experimental Data Sets J Neurophysiol, April 1, 2006; 95(4): 2199 - 2212. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Saltiel, K. Wyler-Duda, A. d'Avella, R. J. Ajemian, and E. Bizzi Localization and Connectivity in Spinal Interneuronal Networks: The Adduction-Caudal Extension-Flexion Rhythm in the Frog J Neurophysiol, September 1, 2005; 94(3): 2120 - 2138. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. C. K. Cheung, A. d'Avella, M. C. Tresch, and E. Bizzi Central and Sensory Contributions to the Activation and Organization of Muscle Synergies during Natural Motor Behaviors J. Neurosci., July 6, 2005; 25(27): 6419 - 6434. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. d'Avella and E. Bizzi Shared and specific muscle synergies in natural motor behaviors PNAS, February 22, 2005; 102(8): 3076 - 3081. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. H. Ting and J. M. Macpherson A Limited Set of Muscle Synergies for Force Control During a Postural Task J Neurophysiol, January 1, 2005; 93(1): 609 - 613. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. B. Hart and S. F. Giszter Modular Premotor Drives and Unit Bursts as Primitives for Frog Motor Behaviors J. Neurosci., June 2, 2004; 24(22): 5269 - 5282. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Straka, S. Holler, F. Goto, F. P. Kolb, and E. Gilland Differential Spatial Organization of Otolith Signals in Frog Vestibular Nuclei J Neurophysiol, November 1, 2003; 90(5): 3501 - 3512. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O. Donchin, J. T. Francis, and R. Shadmehr Quantifying Generalization from Trial-by-Trial Behavior of Adaptive Systems that Learn with Basis Functions: Theory and Experiments in Human Motor Control J. Neurosci., October 8, 2003; 23(27): 9032 - 9045. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Bizzi, A. D'Avella, P. Saltiel, and M. Tresch Book Review: Modular Organization of Spinal Motor Systems Neuroscientist, October 1, 2002; 8(5): 437 - 442. [Abstract] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
