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Simulations reveal large variations in fusimotor action in normal cats: ‘fusimotor set’

  • M. Hulliger
  • P. Zangger
  • A. Prochazka
  • K. Appenteng

Abstract

Since the advent a decade ago of techniques for the recording from single muscle spindle afferents in behaving cats and monkeys, speculation has mounted that γ-fusimotor neurones might, at least in part, be controlled independently of α-motoneurones during normal movement (Loeb & Marks, ibid.; Schieber & Thach, 1980; review: Prochazka & Hulliger, 1983). This has been based largely on qualitative inferences drawn from spindle afferent firing patterns, as direct recordings from fully identified γ-motoneurones in the awake animal have yet to be obtained. The most compelling qualitative evidence for α-γ-independence has been the frequent observation that spindle afferent firing during movement is not closely coupled to the bursts of α-activity of the receptor -bearing muscles. Furthermore, large variations in Ia stretch-sensitivity, without corresponding changes in α-activity, have been observed in movements of different types, suggesting large variations in fusimotor action (Prochazka & Wand, 1981).

Keywords

Chronic Recording Afferent Firing Motor Control Mechanism Masseter Nerve Concomitant Stimulation 
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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References

  1. Appenteng, K., Morimoto, T. & Taylor, A. (1980) Fusimotor activity in masseter nerve of the cat during reflex jaw movements. J.Physiol., 305, 415–432Google Scholar
  2. Hulliger, M. & Prochazka, A. (1983) A new simulation method to deduce fusimotor activity from afferent discharge recorded in freely moving cats. J. Neurosci. Methods 8, 197–204.Google Scholar
  3. Hulliger, M., Zangger, P., Prochazka, A. & Appenteng. K. (1984). Fusimotor “set” vs α-γ linkage in voluntary movement in cats. In: Proc. 7th Int. Cong. of Electromyography, Munich. (eds. A. Struppler and A. Weindl). Berlin; Springer, pp57–64.Google Scholar
  4. Prochazka, A. (1983) Chronic techniques for studying neurophysiology of movement in cats. In: Methods for Neuronal Recording in Conscious Animals (IARO Handbook Series: Methods in the Neurosciences, Vol. 4 ed. Lemon,R.,New York:John Wiley,pp.113–128.Google Scholar
  5. Prochazka, A. & Hulliger, M. (1983) Muscle afferent function and its significance for motor control mechanisms during voluntary movements in cat, monkey and man In: Motor Control Mechanisms in Health and Disease ed. Desmedt, J.E., New York: Raven, pp. 93–132.Google Scholar
  6. Prochazka, A. & Wand, P. (1981) Independence of fusimotor and skeletomotor systems during voluntary movement. In: Muscle Receptors and Movement eds. Taylor,A. & Prochazka,A., London: Macmillan, 229–243.CrossRefGoogle Scholar
  7. Schieber, M.H. & Thach, W.T. (1980) Alpha-gamma dissociation during slow tracking movements of the monkey’s wrist: preliminary evidence from spinal ganglion recording. Brain Res., 202,213–216Google Scholar

Copyright information

© I. A. Boyd and M. H. Gladden 1985

Authors and Affiliations

  • M. Hulliger
    • 1
  • P. Zangger
    • 1
  • A. Prochazka
    • 1
  • K. Appenteng
    • 1
  1. 1.Department of PhysiologyUniversity of LeedsUK

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