Summary
Variations in the sensitivities of primary and secondary muscle spindle afferents were observed in cats performing voluntary movements. The time course of fusimotor action was deduced from these variations. In unobstructed movements, there was evidence of steady, relatively low levels of both static and dynamic action. In imposed movements involving slight to moderate resistance, eight of the nine primary endings studied showed evidence of increased, steady, dynamic action. This may therefore represent a class of movement which is most often associated with a known change in spindle sensitivity in the normal animal. In imposed movements involving substantial resistance, further fusimotor action of both types was implicated. Although there was some evidence for e.m.g.-linked increases in fusimotor action in two of the primaries, it was not possible to decide whether or not these were examples of α–γ linkage. We conclude that much of the functionally important fusimotor action occurring during normal movements in cats is independent of skeletomotor activity.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Alnaes, E., Jansen, J. K. S. and Rudjord, T. (1965). Fusimotor activity in the spinal cat, Acta physiol. scand., 63, 197–212
Appelberg, B. Selective midbrain control of dynamic gamma motoneurons, this publication
Appenteng, K., Morimoto, T. and Taylor, A. (1980). J. Physiol., Lond., to be published
Bergmans, J. and Grillner, S. (1969). Reciprocal control of spontaneous activity and reflex effects in static and dynamic γ-motoneurones revealed by an injection of DOPA, Acta physiol. scand., 77, 106–124
Brown, M. C., Goodwin, G. M. and Matthews, P. B. C. (1969). After-effects of fusimotor stimulation on the response of muscle spindle primary afferent endings, J. Physiol., Lond., 205, 677–694
Brown, M. C. and Matthews, P. B. C. (1966). On the subdivision of the efferent fibres to muscle spindles into static and dynamic fusimotor fibres. In Control and Innervation of Skeletal Muscle (ed. B. L. Andrew), Dundee, Thomson, 18–31
Burke, D., Hagbarth, K.-E. and Skuse, N. F. (1979). Voluntary activation of spindle endings in human muscles temporarily paralysed by nerve pressure, J. Physiol., Lond., 287, 329–336
Granit, R. (1955). Receptors and Sensory Perception, New Haven, Yale University Press
Granit, R. (1979). Interpretation of supraspinal effects on the gamma system. In Reflex Control of Posture and Movement, Prog. Brain Res., 50 (eds. R. Granit and O. Pompeiano), Amsterdam, Elsevier, 147–154
Granit, R., Holmgren, B. and Merton, P. A. (1955). The two routes for excitation of muscle and their subservience to the cerebellum, J. Physiol., Lond., 130, 213–224
Grillner, S., Hongo, T. and Lund, S. (1969). Descending monosynaptic and reflex control of γ-motoneurones, Acta physiol. scand., 75, 592–613
Hagbarth, K.-E. (1980). Fusimotor and stretch reflex functions studied in recordings from muscle spindle afferents in man, this publication
Hasan, Z. and Houk, J. C. (1975). Analysis of response properties of de-efferented mammalian spindle receptors based on frequency response, J. Neurophysiol., 38, 663–672
Houk, J. C., Rymer, W. Z. and Crago, P. E. (1980). Nature of the dynamic response and its relation to the high sensitivity of muscle spindles to small changes in length, this publication
Jami, L. and Petit, J. (1978). Fusimotor actions on sensitivity of spindle secondary endings to slow muscle stretch in cat peroneus tertius, J. Neurophysiol., 41, 860–869
Loeb, G. E. and Duysens, J. (1979). Activity patterns in individual hindlimb primary and secondary muscle spindle afferents during normal movements in unrestrained cats, J. Neurophysiol., 42, 420–440
Loeb, G. E. and Hoffer, J. A. (1980). Muscle spindle function during normal and perturbed locomotion in cats, this publication
Matthews, P. B. C. (1972). Mammalian Muscle Receptors and Their Central Actions, London, Arnold
Matthews, P. B. C. and Stein, R. B. (1969). The sensitivity of muscle spindle afferents to small sinusoidal changes of length, J. Physiol., Lond., 200, 723–743
Poppele, R. E. and Bowman, R. J. (1970). Quantitative description of linear behaviour of mammalian muscle spindles, J. Neurophysiol., 33, 59–72
Post, E., Rymer, W. Z. and Hasan, Z. (1978). Relation between extrafusai and intrafusal activity in the decerebrate cat model: a role for beta fibres, Soc. Neurosci. Abstr., No. 958
Prochazka, A. (1980). Muscle spindle function during normal movement. In MTP Int. Rev. Physiol., Neurophysiology IV (ed. R. Porter), Baltimore, University Park Press, to be published
Prochazka, A., Stephens, J. A. and Wand, P. (1979). Muscle spindle discharge in normal and obstructed movement, J. Physiol., Lond., 287, 57–66
Prochazka, A. and Wand, P. (1980a). Tendon organ discharge during voluntary movements in cats, J. Physiol., Lond., 303, 385–390
Prochazka, A. and Wand, P. (1980b). Fusimotor action during normal movements, deduced from variations in muscle spindle sensitivity, J. Physiol., Lond., to be published
Sherrington, C. S. (1910). Flexion-reflex of the limb, crossed extension-reflex, and reflex stepping and standing, J. Physiol., Lond., 40, 28–121
Taylor, A. and Cody, F. W. J. (1974). Jaw muscle spindle activity in the cat during normal movements of eating and drinking, Brain Res., 71, 523–530
Vallbo, A. B. (1980). Basic patterns of muscle spindle discharge in man, this publication
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Copyright information
© 1981 The contributors
About this chapter
Cite this chapter
Prochazka, A., Wand, P. (1981). Independence of fusimotor and skeletomotor systems during voluntary movement. In: Taylor, A., Prochazka, A. (eds) Muscle Receptors and Movement. Palgrave Macmillan, London. https://doi.org/10.1007/978-1-349-06022-1_24
Download citation
DOI: https://doi.org/10.1007/978-1-349-06022-1_24
Publisher Name: Palgrave Macmillan, London
Print ISBN: 978-1-349-06024-5
Online ISBN: 978-1-349-06022-1
eBook Packages: Biomedical and Life SciencesBiomedical and Life Sciences (R0)