|
|
||||||||
The Journal of Neurophysiology Vol. 80 No. 1 July 1998,
pp. 130-142
Copyright ©1998 The American Physiological Society
Department of Sensorimotor Systems, Division of Neuroscience and Psychological Medicine, Imperial College School of Medicine, Charing Cross Hospital, London W6 8RF, United Kingdom
Taylor, A., P. H. Ellaway, and R. Durbaba. Physiological signs of the activation of bag2 and chain intrafusal muscle fibers of gastrocnemius muscle spindles in the cat. J. Neurophysiol. 80: 130-142, 1998. A method is described for identifying the effect of single gamma static (
s) axons on bag2 or chain intrafusal fibers using random (Poisson-distributed) stimuli. The cross-correlogram of the stimuli with the firing of spindle primary afferents took one of three forms. A large, simple, brief response was taken to indicate pure chain fiber activation and a small, prolonged response to indicate pure bag2 activation. A compound response with brief and prolonged components was taken to be a sign of mixed innervation. The correlogram components could be well fitted with lognormal curves. They could also be transformed into curves of gain as a function of frequency, which were convenient for estimating the strength of the effects. In 68 effects of
s axons on Ia afferents, 16 were pure chain, 17 pure bag2, and 35 mixed. This distribution was significantly different (P < 0.05) from that expected from chance nonspecific innervation of chain and bag2 fibers. Making use of the estimates of the strength of chain and bag2 effects derived from the gain curves, the classification was modified by treating mixed responses that had one effect more than five times stronger than the other as belonging to the dominant type. The distribution was then as follows: chain 16, bag2 28, and mixed 24. This differed very significantly from the prediction of chance distribution (P < 0.001). This evidence for some degree of specific innervation of chain and bag2 fibers is discussed in relation to previous work and with regard to the ways in which the two fiber types might be used in natural movements.
This article has been cited by other articles:
![]() |
V. Hospod, J.-M. Aimonetti, J.-P. Roll, and E. Ribot-Ciscar Changes in Human Muscle Spindle Sensitivity during a Proprioceptive Attention Task J. Neurosci., May 9, 2007; 27(19): 5172 - 5178. [Abstract] [Full Text] [PDF] |
||||
![]() |
R Durbaba, A Taylor, P H Ellaway, and S Rawlinson The influence of bag2 and chain intrafusal muscle fibres on secondary spindle afferents in the cat J. Physiol., July 1, 2003; 550(1): 263 - 278. [Abstract] [Full Text] [PDF] |
||||
![]() |
M H Gladden and H Matsuzaki Static {gamma}-motoneurones couple group Ia and II afferents of single muscle spindles in anaesthetised and decerebrate cats J. Physiol., August 15, 2002; 543(1): 273 - 288. [Abstract] [Full Text] [PDF] |
||||
![]() |
P R Murphy, K G Pearson, and R B Stein Toe flexor muscle spindle discharge and stretch modulation during locomotor activity in the decerebrate cat J. Physiol., August 1, 2002; 542(3): 939 - 949. [Abstract] [Full Text] [PDF] |
||||
![]() |
R Durbaba, A Taylor, P H Ellaway, and S Rawlinson Modulation of primary afferent discharge by dynamic and static gamma motor axons in cat muscle spindles in relation to the intrafusal fibre types activated J. Physiol., April 15, 2001; 532(2): 563 - 574. [Abstract] [Full Text] [PDF] |
||||
![]() |
A Taylor, P H Ellaway, R Durbaba, and S Rawlinson Distinctive patterns of static and dynamic gamma motor activity during locomotion in the decerebrate cat J. Physiol., December 15, 2000; 529(3): 825 - 836. [Abstract] [Full Text] [PDF] |
||||
![]() |
M H Gladden, D J Maxwell, A Sahal, and E Jankowska Coupling between serotoninergic and noradrenergic neurones and {gamma}-motoneurones in the cat J. Physiol., September 1, 2000; 527(2): 213 - 223. [Abstract] [Full Text] [PDF] |
||||
![]() |
A Taylor, R Durbaba, P H Ellaway, and S Rawlinson Patterns of fusimotor activity during locomotion in the decerebrate cat deduced from recordings from hindlimb muscle spindles J. Physiol., February 1, 2000; 522(3): 515 - 532. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Petit, R. W. Banks, and Y. Laporte Testing the Classification of Static gamma Axons Using Different Patterns of Random Stimulation J Neurophysiol, June 1, 1999; 81(6): 2823 - 2832. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |