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Some Unresolved Issues in Motor Unit Research

  • Robert E. Burke
Chapter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 508)

Abstract

The intrinsic properties of motoneurones, muscle units, and synaptic inputs exhibit correlated variations that subserve a wide range of functional demands. In large limb muscles, these correlations suggest distinct “types” of motor units, while in smaller, distal muscles their distributions are more continuous. The CNS mechanisms that control recruitment patterns are still unclear, particularly the organization of spinal interneurone circuits. We need new approaches to identify segmental interneurones by their inputs and output targets. Howeverfunctionalcircuitry is changeable, depending on the “state” of the system. Shifting alliances of interneurone groups can in principle produce virtually unlimited permutations of motor unit coactivation and suppression. Although such state-dependence plasticity is a challenge, it can also be a useful tool in unraveling interneurone organization.

Keywords

Motor Unit Experimental Brain Research Spinal Mechanism Selective Recruitment Size Principle 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 2002

Authors and Affiliations

  • Robert E. Burke
    • 1
  1. 1.Laboratory of Neural Control, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaUSA

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