Principles of Force Gradation in Skeletal Muscles

[摘要] A brief survey is given of how motoneuronsand motor units are used for the gradation Ofmuscle force during motor behavior. Basicproperties of motoneurons and muscle fibers,including major kinds of functional specializationalong the axis of ‘fast’ vs. ‘slow’, are reviewed.The principles underlying the rate and recruitmentgradation of force are described, stressingthat the properties of motoneurons and musclefibers are matched to automate importantaspects of the gradation procedure. Recentinvestigations concerning synaptically evokedchanges in the discharge properties of motoneuronsreceive special attention, including‘plateau’ currents and, under appropriateconditions, self-sustained ‘plateau’ discharges.

[学科分类] 精神健康和精神病学