HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 91/5/2380    most recent 01184.2003v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (10) Citing Articles via Google Scholar Google Scholar Articles by Stein, P. S. G. Articles by Daniels-McQueen, S. Search for Related Content PubMed PubMed Citation Articles by Stein, P. S. G. Articles by Daniels-McQueen, S.

Report

Variations in Motor Patterns During Fictive Rostral Scratching in the Turtle: Knee-Related Deletions

Department of Biology, Washington University, St. Louis, Missouri 63130

Submitted 9 December 2003; accepted in final form 7 January 2004

Agonist motor neurons usually alternate between activity and quiescence during normal rhythmic behavior; antagonist motor neurons are usually active during agonist motor neuron quiescence. During an antagonist deletion, a naturally occurring motor-pattern variation, there is no antagonist activity and no quiescence between successive bursts of agonist activity. Motor neuron recordings of normal fictive rostral scratching in the turtle displayed rhythmic alternation between activity and quiescence for hip flexors, knee flexors, and knee extensors. Knee-flexor activity occurred during knee-extensor quiescence. During a hip-extensor deletion, a variation of rostral scratching, rhythmic hip-flexor bursts occurred without intervening hip-flexor quiescence. There were 3 distinct patterns of knee motor activity during the cycle before or after a hip-extensor deletion. In most cycles, there was knee flexor-extensor rhythmic alternation. In some cycles, termed knee-flexor deletions, there was no knee-flexor activity and rhythmic knee-extensor bursts occurred without intervening knee-extensor quiescence. In other cycles, termed knee-extensor deletions, there was no knee-extensor activity and rhythmic knee-flexor bursts occurred without intervening knee-flexor quiescence. The concept of a module refers to a population of motor neurons and interneurons with similar activity patterns; interneurons in a module coordinate agonist and antagonist motor neuron activities, either with excitation of agonist motor neurons and interneurons, or with inhibition of antagonist motor neurons and interneurons. Previous studies of hip-extensor deletions support the concept of a rhythmogenic hip-flexor module. The knee-related deletions described here support the concept of rhythmogenic knee-flexor and knee-extensor modules linked by reciprocal inhibition.

This article has been cited by other articles:

				C. F. Honeycutt, J. S. Gottschall, and T. R. Nichols Electromyographic Responses From the Hindlimb Muscles of the Decerebrate Cat to Horizontal Support Surface Perturbations J Neurophysiol, June 1, 2009; 101(6): 2751 - 2761. [Abstract] [Full Text] [PDF]

				N. S. Bradley, Y. U. Ryu, and J. Lin Fast Locomotor Burst Generation in Late Stage Embryonic Motility J Neurophysiol, April 1, 2008; 99(4): 1733 - 1742. [Abstract] [Full Text] [PDF]

				K. E. Musselman and J. F. Yang Loading the Limb During Rhythmic Leg Movements Lengthens the Duration of Both Flexion and Extension in Human Infants J Neurophysiol, February 1, 2007; 97(2): 1247 - 1257. [Abstract] [Full Text] [PDF]

				M. G. Sirota, G. A. Pavlova, and I. N. Beloozerova Activity of the Motor Cortex During Scratching J Neurophysiol, February 1, 2006; 95(2): 753 - 765. [Abstract] [Full Text] [PDF]

				H. Ye, D. W. Morton, and H. J. Chiel Neuromechanics of Coordination during Swallowing in Aplysia californica J. Neurosci., February 1, 2006; 26(5): 1470 - 1485. [Abstract] [Full Text] [PDF]

				A. W. Jackson, D. F. Horinek, M. R. Boyd, and A. D. McClellan Disruption of Left-Right Reciprocal Coupling in the Spinal Cord of Larval Lamprey Abolishes Brain-Initiated Locomotor Activity J Neurophysiol, September 1, 2005; 94(3): 2031 - 2044. [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]

				M. Lafreniere-Roula and D. A. McCrea Deletions of Rhythmic Motoneuron Activity During Fictive Locomotion and Scratch Provide Clues to the Organization of the Mammalian Central Pattern Generator J Neurophysiol, August 1, 2005; 94(2): 1120 - 1132. [Abstract] [Full Text] [PDF]

				J. F. Yang, E. V. Lamont, and M. Y. C. Pang Split-Belt Treadmill Stepping in Infants Suggests Autonomous Pattern Generators for the Left and Right Leg in Humans J. Neurosci., July 20, 2005; 25(29): 6869 - 6876. [Abstract] [Full Text] [PDF]