Skip to main content
SpringerLink
Log in

Comparison of Effective Synaptic Currents Generated in Spinal Motoneurons by Activating Different Input Systems

  • Chapter
Biomechanics and Neural Control of Posture and Movement

Abstract

Understanding how synaptic inputs from segmental and descending systems shape motor output from the spinal cord requires descriptions of the relative magnitudes of the synaptic currents produced by the different systems and their patterns of distribution within a motoneuron pool (Anderson and Binder 1989; Binder 1989). Although most quantitative assessments of the synaptic input to motoneurons are based on measurements of the amplitude of postsynaptic potentials (PSPs; rev. in Binder and Mendell, 1990; Binder et al. 1996), my colleagues and I have argued that the synaptic current reaching the soma (i.e., the “effective synaptic current”) is a more functionally relevant measure of the magnitude of a synaptic input (Heckman and Binder, 1988, 1990, 1991b; Lindsay and Binder 1991; Binder et al. 1993, 1996, 1998; Powers et al. 1992, 1993; Binder and Powers 1995a; Westcott et al. 1995).

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Log in via an institution
Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 259.00
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 329.00
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 329.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  • Anderson, M.E. and Binder, M.D. (1989). Spinal and Supraspinal Control of Movement and Posture. In Textbook of Physiology, 21st ed. Patton, H.D., Fuchs, A.F., Hille, B., Scher, A.M., and Steiner, R. (eds.), Chapter 26, pp. 563–581, W.B. Saunders, Philadelphia.

    Google Scholar 

  • Binder, M.D. (1989). Functional organization of motoneuron pools. In Textbook of Physiology, 21st ed. Patton, H.D., Fuchs, A.F., Hille, B., Scher, A.M., and Steiner, R. (eds.), Chapter 25, pp. 549–562, W.B. Saunders, Philadelphia.

    Google Scholar 

  • Binder, M.D. and Mendell, L.Mi (1990); The Segmentai Motor System. Oxford University Press, New York.

    Google Scholar 

  • Binder, M.D. and Powers, R.K. (1995). Effective synaptic currents generated in eat spinal motoneurons by activating descending and peripheral afferent fibers. In Alpha and Gamma Motor Systems. Taylor, A., Gladden, M., and Durbaba, R. (eds.), pp. 14–22, Plenum Press, New York.

    Google Scholar 

  • Binder, M.D. and Powers, R.K. (1999). Synaptic integration in spinal motoneurons. J. Physiol. (Paris), 93:71–79.

    Article  CAS  Google Scholar 

  • Binder, M.D., Heckman, C.J., and Powers, R.K. (1993). How different afferent inputs control motoneuron discharge and the output of the motoneuron pool. Curr. Opin. Neurobiol., 3(6):1028–1034.

    Article  PubMed  CAS  Google Scholar 

  • Binder, M.D., Heckman, C.J., and Powers, R.K. (1996). The physiological control of motoneuron activity. In Handbook of Physiology. Section 12, Exercise: Regulation and Integration of Multiple Systems. Rowell, L.B. and Shepherd, J.T. (eds.), pp. 3–53, American Physiological Society, New York, Oxford.

    Google Scholar 

  • Binder, M.D., Robinson, F.R., and Powers, R.K. (1998). Distribution of effective synaptic currents in cat triceps surae motoneurons. VI. Contralateral pyramidal tract. J. Neurophysiol, 80:241–248.

    PubMed  CAS  Google Scholar 

  • Burke, R.E., Jankowska, E., and ten Bruggencate, G. (1970). A comparison of peripheral and rubrospinal input to slow and fast twitch motor units of triceps surae. J. Physiol. (London), 207:709–732.

    CAS  Google Scholar 

  • Burke, R.E., Rymer, W.Z., and Walsh, J.V. (1976). Relative strength of synaptic input from short-latency pathways to motor units of defined type in cat medial gastrocnemius. J. Neurophysiol., 39:447–58.

    PubMed  CAS  Google Scholar 

  • Cullheim, S. and Kellerth, J. (1978). A morphological study of the axons and recurrent axon collaterals of cat a-motoneurones supplying different functional types of muscle unit. J. Physiol. (London), 281:301–313.

    CAS  Google Scholar 

  • Dum, R.P. and Kennedy, T.T. (1980). Synaptic organization of defined motor unit types in cat tibialis anterior. J. Neurophysiol. 43:1631–1644.

    PubMed  CAS  Google Scholar 

  • Eccles, J.C., Eccles, R.M., Iggo, A., and Ito, M. Distribution of recurrent inhibition among motoneurons. J. Physiol (London), 159:479–499, 1961.

    CAS  Google Scholar 

  • Endo, K., Araki, T., and Kawai, Y. (1975). Contra- and ipsilateral cortical and rubral effects on fast and slow spinal motoneurons of the cat. Brain Res. 88:91–98.

    Article  PubMed  CAS  Google Scholar 

  • Friedman, W.A., Sypert, G.W., Munson, J.B., and Fleshman, J.W. (1981). Recurrent inhibition in type-identified motoneurons. J. Neurophysiol., 46:1349–59.

    PubMed  CAS  Google Scholar 

  • Fuglevand, A.J., Winter, D.A., and Patla, A.E. (1993). Models of recruitment and rate coding organization in motor-unit pools. J. Neurophysiol., 70:2470–2488.

    PubMed  CAS  Google Scholar 

  • Fukushima, K., Peterson, B.W., and Wilson, V.J. (1979). Vestibulospinal, reticulospinal and interstitiospinal pathways in the cat. Prog. Brain Res., 50:121–136.

    Article  PubMed  CAS  Google Scholar 

  • Granit, R., and Renkin, B. (1961). Net depolarization and discharge rate of motoneurones, as measured by recurrent inhibition. J. Physiol. (London), 158:461–475.

    CAS  Google Scholar 

  • Granit, R., Kernell, D., and Lamarre, Y. (1966). Algebraical summation in synaptic activation of motoneurones firing within the ‘primary range’ to injected currents. J. Physiol. (London), 187:379–99.

    CAS  Google Scholar 

  • Grillner, S., Hongo, T., and Lund, S. (1970). The vestibulospinal tract. Effects on alpha-motoneurones in the lumbosacral spinal cord in the cat. Exp. Brain Res., 10:94–120.

    Article  PubMed  CAS  Google Scholar 

  • Heckman, C.J. (1994). Computer simulations of the effects of different synaptic input systems on the steady-state input-output structure of the motoneuron pool. J. Neurophysiol., 71:1717–1739.

    Google Scholar 

  • Heckman, C.J. and Binder, M.D. (1988). Analysis of effective synaptic currents generated by homonymous Ia afferent fibers in motoneurons of the cat. J. Neurophysiol., 60:1946–1966.

    PubMed  CAS  Google Scholar 

  • Heckman, C.J. and Binder, M.D. (1990). Neural mechanisms underlying the orderly recruitment of motoneurons. In The Segmental Motor System. Binder, M.D. and Mendell, L.M. (eds.), pp. 182–204, Oxford University Press, New York.

    Google Scholar 

  • Heckman, C.J. and Binder, M.D. (1991a). Computer simulation of the steady-state input-output function of the cat medial gastrocnemius motoneuron pool. J. Neurophysiol., 65:952–967.

    PubMed  CAS  Google Scholar 

  • Heckman, C.J. and Binder, M.D. (1991b). Analysis of Ia-inhibitory synaptic input to cat spinal motoneurons evoked by vibration of antagonist muscles. J. Neurophysiol., 66:1888–1893.

    PubMed  CAS  Google Scholar 

  • Heckman, C.J. and Binder, M.D. (1993a). Computer simulations of motoneuron firing rate modulation. J. Neurophysiol., 69:1005–1008.

    PubMed  CAS  Google Scholar 

  • Heckman, C.J. and Binder, M.D. (1993b). Computer simulations of the effects of different synaptic input systems on motor unit recruitment. J. Neurophysiol., 70:1827–1840.

    PubMed  CAS  Google Scholar 

  • Heckman, C.J., Weytjens, J.L.F., and Loeb, G.E. (1993). Effect of velocity and mechanical history on the forces of motor units in the cat medial gastrocnemius muscle. J. Neurophysiol., 68:1503–1115.

    Google Scholar 

  • Henneman, E., Somjen, G., and Carpenter, D.O. (1965). Excitability and inhibitability of motoneurons of different sizes. J. Neurophysiol., 28:599–620.

    PubMed  CAS  Google Scholar 

  • Hongo, T., Jankowska, E., and Lundberg, A. (1969). The rubrospinal tract. I. Effects on alpha-motoneurones innervating hindlimb muscles in cats. Exp. Brain Res., 7:344–64.

    PubMed  CAS  Google Scholar 

  • Hultborn, H., Katz, R., and Mackel, R. (1988). Distribution of recurrent inhibition within a motor nucleus. II. Amount of recurrent inhibition in motoneurons to fast and slow units. Acta Physiologica Scandinavia, 134:363–374.

    Article  CAS  Google Scholar 

  • Hultborn, H., Lindstrom, S., and Wigstrom, H. (1979). On the function of recurrent inhibition in the spinal cord. Exp. Brain Res., 37:399–403.

    Article  PubMed  CAS  Google Scholar 

  • Kernell, D. (1966). The repetitive discharge of motoneurones. In Muscular Afferents and Motor Control. Nobel Symp. I. Granit, R. (eds.), pp. 351–362, Almqvist and Wiksell, Stockholm.

    Google Scholar 

  • Kernell, D. (1970). Synaptic conductance changes and the repetitive impulse discharge of spinal motoneurones. Brain Res., 15:291–294.

    Article  Google Scholar 

  • Kernell, D. (1979). Rhythmic properties of motoneurones innervating muscle fibres of different speed in m. gastrocnemius medialis of the cat. Brain Res., 160:159–62.

    Article  PubMed  CAS  Google Scholar 

  • Lee, R.H. and Heckman, C.J. (1996). Influence of voltage-sensitive conductances on bistable firing and effective synaptic current in cat spinal motoneurons in vivo. J. Neurophysiol., 76:2107–2110.

    PubMed  CAS  Google Scholar 

  • Lindsay, A.D. and Binder, M.D. (1991). Distribution of effective synaptic currents underlying recurrent inhibition in cat triceps surae motoneurons. J. Neurophysiol., 65:168–117.

    PubMed  CAS  Google Scholar 

  • Munson, J.B. (1990). Synaptic inputs to type-identified motor units. In The Segmental Motor System. Binder, M.D. and Mendell, L.M. (eds.), pp. 291–307, New York: Oxford University Press.

    Google Scholar 

  • Poliakov, A.V., Powers, R.K., and Binder, M.D. (1996). Dynamic responses of motoneurons to current transients studied with the white noise method. Soc. Neurosci. Abstr., 22:1845.

    Google Scholar 

  • Poliakov, A.V., Powers, R.K., Sawczuk, A., and Binder, M.D. (1996). Effects of background noise on the response of motoneurons to excitatory current transients. J. Physiol. (London), 495:143–157.

    Google Scholar 

  • Powers, R.K. and Binder, M.D. (1995a). Effective synaptic current and motoneuron firing rate modulation. J. Neurophysiol., 74:793–810.

    PubMed  CAS  Google Scholar 

  • Powers, R.K. and Binder, M.D. (1995b). Quantitative analysis of motoneuron firing rate modulation in response to simulated synaptic inputs. In Alpha and Gamma Motor Systems. Taylor, A., Gladden, M., and Durbaba, R. (eds.), pp. 42–44, Plenum Press, New York.

    Google Scholar 

  • Powers, R.K. and Binder, M.D. (1996). Experimental evaluation of input -output models of motoneuron discharge. J. Neurophysiol., 75:367–379.

    PubMed  CAS  Google Scholar 

  • Powers, R.K. and Binder, M.D. (2000). Summation of effective synaptic currents and firing rate modulation in cat spinal motoneurons produced by concurrent stimulation of different synaptic input systems. J. Neurophysiol. (in press).

    Google Scholar 

  • Powers, R.K., Robinson, F.R., Konodi, M.A., and Binder, M.D. (1992). Effective synaptic current can be estimated from measurements of neuronal discharge. J. Neurophysiol., 68:964–968.

    PubMed  CAS  Google Scholar 

  • Powers, R.K., Robinson, F.R., Konodi, M.A., and Binder, M.D. (1993). Distribution of rubrospinal synaptic input to cat triceps surae motoneurons. J. Neurophysiol., 70:1460–1468.

    PubMed  CAS  Google Scholar 

  • Schwindt, P.C. and Calvin, W.H. (1973a). Equivalence of synaptic and injected current in determining the membrane potential trajectory during motoneuron rhythmic firing. Brain Res., 59:389–94.

    Article  PubMed  CAS  Google Scholar 

  • Schwindt, P.C. and Calvin, W.H. (1973b). Nature of conductances underlying rhythmic firing in cat spinal motoneurons. J. Neurophysiol., 36:955–973.

    PubMed  CAS  Google Scholar 

  • Shapovalov, A.I. (1972). Extrapyramidal monosynaptic and disynaptic control of mammalian alpha-motoneurons. Brain Res., 40:105–115.

    Article  PubMed  CAS  Google Scholar 

  • Shinoda, Y., Ohgaki, T., Futami, T., and Sugiuchi, Y. (1988). Structural basis for three-dimensional coding in the vestibulospinal reflex. Ann. New York Acad. Sci., 545:216–227.

    Article  CAS  Google Scholar 

  • Shinoda, Y., Ohgaki, T., Futami, T., and Sugiuchi, Y. (1988b). Vestibular projections to the spinal cord: the morphology of single vestibulospinal axons. Prog. Brain Res., 76:17–27.

    Article  PubMed  CAS  Google Scholar 

  • Stein, R.B. and Bertoldi, R. (1989). The size principle: a synthesis of neurophysiological data. In Progress in Clinical Neurophysiology. Motor Unit Types, Recruitment, and Plasticity in Health and Disease. Desmedt, J.E. (ed.), pp. 85–96, Basel, Karger.

    Google Scholar 

  • Westcott, S.L. (1993). Comparison of vestibulospinal synaptic input and Ia afferent synaptic input in cat triceps surae motoneurons. PhD dissertation, University of Washington.

    Google Scholar 

  • Westcott, S.L., Powers, R.K., Robinson, F.R., and Binder, M.D. (1995). Distribution of vestibulospinal input to cat triceps surae motoneurons. Exp. Brain Res., 107:1–8.

    Article  PubMed  CAS  Google Scholar 

References

  • Brink, E., Jankowska, E., McCrea, D.A., and Skoog, B. (1983). Inhibitory interactions between interneurones in reflex pathways form group Ia and group Ib afferents in the cat. J. Physiol., (London), 343:361–373.

    CAS  Google Scholar 

  • Burke, R.E. and Glenn, L.L. (1996). Horseradish peroxidase study of the spatial and electrotonic distribution of group Ia synapses on type-identified ankle extensor motoneurons in the cat. J. Neurophysiol., 372:465–485.

    CAS  Google Scholar 

  • Burke, R.E., Fedina, L., and Lundberg, A. (1971). Spatial synaptic distribution of recurrent and group Ia inhibitory systems in cat spinal motoneurones. J. Physiol., (London), 214:305–326.

    CAS  Google Scholar 

  • Edgley, S.A. and Jankowska, E. (1987). An interneuronal relay for group I and II muscle afferents in the midlumbar segments of the cat spinal cord. J. Physiol., (London), 389:647–674.

    CAS  Google Scholar 

  • Harrison, P.J. and Jankowska, E. (1985). Organization of input to the interneurones mediating group I non-reciprocal inhibition of motoneurones in the cat. J. Physiol., (London), 361:403–418.

    CAS  Google Scholar 

  • McCurdy, M.L. and Hamm, T.M. (1994). Spatial and temporal features of recurrent facilitation among motoneurons innervating synergistic muscles of the cat. J. Neurophysiol. 72:227–234.

    PubMed  CAS  Google Scholar 

  • Rose, P.K., Jones, T., Nirula, R., and Corneil, T. (1995). Innervation of motoneurons based on dendritic orientation. J. Neurophysiol., 73:1319–1322.

    PubMed  CAS  Google Scholar 

Download references

Authors
  1. Marc D. Binder
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Thomas M. Hamm
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Mitchell G. Maltenfort
    View author publications

    You can also search for this author in PubMed Google Scholar

Editor information

Editors and Affiliations

  1. Biomedical Engineering Department, Marquette University, Milwaukee, WI, 53201, USA

    Jack M. Winters

  2. Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, USA

    Patrick E. Crago

Rights and permissions

Reprints and permissions

Copyright information

© 2000 Springer-Verlag New York, Inc.

About this chapter

Cite this chapter

Binder, M.D., Hamm, T.M., Maltenfort, M.G. (2000). Comparison of Effective Synaptic Currents Generated in Spinal Motoneurons by Activating Different Input Systems. In: Winters, J.M., Crago, P.E. (eds) Biomechanics and Neural Control of Posture and Movement. Springer, New York, NY. https://doi.org/10.1007/978-1-4612-2104-3_4

Download citation

  • DOI: https://doi.org/10.1007/978-1-4612-2104-3_4

  • Publisher Name: Springer, New York, NY

  • Print ISBN: 978-1-4612-7415-5

  • Online ISBN: 978-1-4612-2104-3

  • eBook Packages: Springer Book Archive

Publish with us

Policies and ethics

Search

Navigation