JN Watch the video to learn how APS reaches out to developing nations.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Neurophysiol 87: 1542-1553, 2002;
0022-3077/02 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (30)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Yakovenko, S.
Right arrow Articles by Prochazka, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Yakovenko, S.
Right arrow Articles by Prochazka, A.

The Journal of Neurophysiology Vol. 87 No. 3 March 2002, pp. 1542-1553
Copyright ©2002 by the American Physiological Society

Spatiotemporal Activation of Lumbosacral Motoneurons in the Locomotor Step Cycle

Sergiy Yakovenko,1 Vivian Mushahwar,1 Veronique VanderHorst,2 Gert Holstege,2 and Arthur Prochazka1

 1Center for Neuroscience, University of Alberta, Edmonton, Alberta T6G 2S2, Canada; and  2Department of Anatomy, University of Groningen, 9713 AV Groningen, The Netherlands

Yakovenko, Sergiy, Vivian Mushahwar, Veronique VanderHorst, Gert Holstege, and Arthur Prochazka. Spatiotemporal Activation of Lumbosacral Motoneurons in the Locomotor Step Cycle. J. Neurophysiol. 87: 1542-1553, 2002. The aim of this study was to produce a dynamic model of the spatiotemporal activation of ensembles of alpha motoneurons (MNs) in the cat lumbosacral spinal cord during the locomotor step cycle. The coordinates of MNs of 27 hindlimb muscles of the cat were digitized from transverse sections of spinal cord spanning the entire lumbosacral enlargement from the caudal part of L4 to the rostral part of S1 segments. Outlines of the spinal cord gray matter were also digitized. Models of the spinal cord were generated from these digitized data and displayed on a computer screen as three-dimensional (3-D) images. We compiled a chart of electromyographic (EMG) profiles of the same 27 muscles during the cat step cycle from previous studies and used these to modulate the number of active MNs in the 3-D images. The step cycle was divided into 100 equal intervals corresponding to about 7 ms each for gait of moderate speed. For each of these 100 intervals, the level of EMG of each muscle was used to scale the number of dots displayed randomly within the volume of the corresponding MN pool in the digital model. One hundred images of the spinal cord were thereby generated, and these could be played in sequence as a continuous-loop movie representing rhythmical stepping. A rostrocaudal oscillation of activity in hindlimb MN pools emerged. This was confirmed by computing the locus of the center of activation of the MNs in the 100 consecutive frames of the movie. The caudal third of the lumbosacral enlargement showed intense MN activity during the stance phase of locomotion. During the swing phase, the focus of activation shifted abruptly to the rostral part of the enlargement. At the stance-swing transition, a transient focus of activity formed in the most caudal part of the lumbosacral enlargement. This was associated with activation of gracilis, posterior biceps, posterior semimembranosus, and semitendinosus muscles. These muscles move the foot back and up to clear the ground during locomotion, a role that could be described as retraction. The spatiotemporal distribution of neuronal activity in the spinal cord during normal locomotion with descending control and sensory inputs intact has not been visualized before. The model can be used in the future to characterize spatiotemporal activity of spinal MNs in the absence of descending and sensory inputs and to compare these to spatiotemporal patterns in spinal MNs in normal locomotion.




This article has been cited by other articles:


Home page
 J. Neurophysiol.Home page
A. Frigon and S. Rossignol
Short-Latency Crossed Inhibitory Responses in Extensor Muscles During Locomotion in the Cat
J Neurophysiol, February 1, 2008; 99(2): 989 - 998.
[Abstract] [Full Text] [PDF]

Home page
 Neurorehabil Neural RepairHome page
G. Scivoletto, Y. Ivanenko, B. Morganti, R. Grasso, M. Zago, F. Lacquaniti, J. Ditunno, and M. Molinari
Review Article: Plasticity of Spinal Centers in Spinal Cord Injury Patients: New Concepts for Gait Evaluation and Training
Neurorehabil Neural Repair, July 1, 2007; 21(4): 358 - 365.
[Abstract] [PDF]

Home page
 J. Neurophysiol.Home page
L. Guevremont, J. A. Norton, and V. K. Mushahwar
Physiologically Based Controller for Generating Overground Locomotion Using Functional Electrical Stimulation
J Neurophysiol, March 1, 2007; 97(3): 2499 - 2510.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
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]

Home page
 NeuroscientistHome page
Y. P. Ivanenko, R. E. Poppele, and F. Lacquaniti
Motor Control Programs and Walking
Neuroscientist, August 1, 2006; 12(4): 339 - 348.
[Abstract] [PDF]

Home page
 J. Neurophysiol.Home page
Y. P. Ivanenko, R. E. Poppele, and F. Lacquaniti
Spinal Cord Maps of Spatiotemporal Alpha-Motoneuron Activation in Humans Walking at Different Speeds
J Neurophysiol, February 1, 2006; 95(2): 602 - 618.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurosci.Home page
Y. P. Ivanenko, G. Cappellini, N. Dominici, R. E. Poppele, and F. Lacquaniti
Coordination of Locomotion with Voluntary Movements in Humans
J. Neurosci., August 3, 2005; 25(31): 7238 - 7253.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
K. J. Christie and P. J. Whelan
Monoaminergic Establishment of Rostrocaudal Gradients of Rhythmicity in the Neonatal Mouse Spinal Cord
J Neurophysiol, August 1, 2005; 94(2): 1554 - 1564.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
A. Buschges
Sensory Control and Organization of Neural Networks Mediating Coordination of Multisegmental Organs for Locomotion
J Neurophysiol, March 1, 2005; 93(3): 1127 - 1135.
[Abstract] [Full Text] [PDF]

Home page
 BrainHome page
R. Grasso, Y. P. Ivanenko, M. Zago, M. Molinari, G. Scivoletto, V. Castellano, V. Macellari, and F. Lacquaniti
Distributed plasticity of locomotor pattern generators in spinal cord injured patients
Brain, May 1, 2004; 127(5): 1019 - 1034.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
Y. P. Ivanenko, R. E. Poppele, and F. Lacquaniti
Five basic muscle activation patterns account for muscle activity during human locomotion
J. Physiol., April 1, 2004; 556(1): 267 - 282.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
Y. P. Ivanenko, R. Grasso, M. Zago, M. Molinari,, G. Scivoletto, V. Castellano, V. Macellari, and F. Lacquaniti,
Temporal Components of the Motor Patterns Expressed by the Human Spinal Cord Reflect Foot Kinematics
J Neurophysiol, November 1, 2003; 90(5): 3555 - 3565.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
I. Strauss and A. Lev-Tov
Neural Pathways Between Sacrocaudal Afferents and Lumbar Pattern Generators in Neonatal Rats
J Neurophysiol, February 1, 2003; 89(2): 773 - 784.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online