Central and Reflex Recruitment of Crayfish Leg Motoneurones
The reflex pathways of the crayfish thoracocoxal (leg to body) joint are reviewed as a model system for studying central and feedback control of movement. Movement of this joint can evoke both positive and negative feedback reflexes via parallel reflex pathways. Transmission in these pathways depends on central factors, such as the phase of centrally generated motor output. In addition, reflex responses are not uniform within a pool of motoneurones: positive feedback reflexes are restricted to subgroups of a motor pool. Thus, selective recruitment of motoneurones by the CNS could potentially bring about different reflex effects. Finally, selective neuromodulation of reflex pathways is described. The amine, octopamine, abolishes positive feedback reflexes, but leaves negative feedback reflexes relatively unaffected.
KeywordsReflex Response Thoracic Ganglion Feedback Group Reflex Pathway Proprioceptive Input
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