An Example of 2:1 Interlimb Coordination During Fictive Rostral Scratching in a Spinal Turtle. Paul S.G. Stein and Margaret L. McCullough. Department of Biology, Washington University, St. Louis, Missouri 63130
APStracts 4:328N, 1997.
ABSTRACT
An Example of 2:1 Interlimb Coordination During Fictive Rostral Scratching in a Spinal Turtle. Submitted to the Journal of Neurophysiology. The usual interlimb coordination pattern during fictive rostral scratching in turtles is 1:1 coordination. We describe an example in a turtle of 2:1 coordination during fictive rostral scratching in which there were 2 cycles of ipsilateral hip flexor activity during each cycle of contralateral hip extensor activity. During 2:1 coordination, there were fluctuations in the ipsilateral hip flexor cycle period such that a larger ipsilateral hip flexor normalized period, which was associated with the onset of a contralateral hip extensor burst, alternated with a smaller ipsilateral hip flexor normalized period, which was associated with the absence of the onset of a contralateral hip extensor burst. These observations support the concept that contralateral circuitry modulates the timing of ipsilateral motor rhythms and therefore contributes to the production of the ipsilateral motor pattern for rostral scratching.

Received 30 September 1997; accepted in final form 14 November 1997.
APS Manuscript Number J797-7
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1997 The American Physiological Society.
Published in APStracts on 12 December 1997