Pflügers Archiv

, Volume 398, Issue 4, pp 318–323 | Cite as

Changes of steady state activity in motor cortex consistent with the length-tension relation of muscle

  • Christoph Fromm
Excriable Tissues and Contral Nervous Physiology


Steady state activity of motor cortex (MI) neurons and muscles was examined in relation to joint position. Two monkeys performed either isometric or load-bearing isotonic contractions, at different joint positions and during variation of steady torque. In either condition, MI steady state firing rates were found to be related to the amount of muscular excitation necessary to adjust muscle tension to length at any given position and load. The results obtained from 526 neurons (including pyramidal tract neurons) demonstrate for 206 neurons a correlate of the length-tension relation of muscle in the motor cortex.

Key words

Motor cortex Monkey Single neuron recording Steady position control Length-tension relationship 


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Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • Christoph Fromm
    • 1
  1. 1.Abteilung NeurobiologieMax-Planck-Institut für biophysikalische ChemieGöttingenFederal Republic of Germany

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