Abstract
It is now well known that, in the cat, locomotor movements can be elicited in spinal or decerebrate preparations, or occur spontaneously in premammillary decerebrate, thalamic or decorticate preparations (see Grillner, 1981). Following paralysis by curarization, efferent nerve discharges closely related to the electromyograms and movements of the non-paralyzed animal (see Perret, 1983) can be recorded in these preparations. This complex and variable activity termed “fictive locomotion” represents, in each limb, the output of a central pattern generator for locomotion, uninfluenced by phasic afferent inputs linked to movements. However, tonic afferent inputs are still present after curarization. Although not essential for the locomotor activity, they may participate in the organization of the step cycle, as shown by the effects of modifications of the joint angles (Perret, 1976), of tonic exteroceptive stimulations (Perret and Cabelguen, 1980; Cabelguen et al, 1981; Fleshman et al., 1984) and of deafferentation (Perret and Cabelguen, 1976) of the limb. We postulated (see Perret, 1983) that the final pattern of efferent activity during fictive locomotion is elaborated by an output network which receives converging influences from a central generator and from reflex afferents.
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© 1986 The Wenner-Gren Center
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Perret, C. (1986). Synaptic Influences Contributing to the Pattern of Limb Motoneuron Activity during Fictive Locomotion in the Cat. In: Grillner, S., Stein, P.S.G., Stuart, D.G., Forssberg, H., Herman, R.M. (eds) Neurobiology of Vertebrate Locomotion. Wenner-Gren Center International Symposium Series. Palgrave Macmillan, London. https://doi.org/10.1007/978-1-349-09148-5_12
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DOI: https://doi.org/10.1007/978-1-349-09148-5_12
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