Abstract
A model for the summation of the fibre potentials in a motor unit is presented. A possible mechanism for the recruitment sequence of the various fibres of a motor unit is developed on the basis of anatomical and physiological findings supplemented with a mathematical approach making it possible to take into consideration the spatial and temporal distribution of various fibre potentials. In addition to the commonly accepted parameters of a motor unit potential, stress is laid on the relative position of the recording electrode with respect to the structure of the motor unit and the location of the motor point of the muscle. The model is evaluated both with dipole and dielectric attenuation approaches.
The sub-unit concept of a motor unit is critically examined in the light of the results of the model.
Attention has been focused on the motor units of the brachial biceps, but the flexibility of the approach also makes it possible to consider motor units of other muscles. The procedure for such generalisations and the respective limitations are discussed. The model provides a unified approach to the diversity of the parameters of the motor unit potential.
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Wani, A.M., Guha, S.K. Synthesising of a motor unit potential based on the sequential firing of muscle fibres. Med. Biol. Eng. Comput. 18, 719–726 (1980). https://doi.org/10.1007/BF02441896
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DOI: https://doi.org/10.1007/BF02441896