The Effectiveness of Individual Synaptic Inputs with Uniform and Nonuniform Patterns of Background Synaptic Activity

  • William R. Holmes
  • Charles D. Woody


The effectiveness of a synaptic input in changing the potential at the soma depends strongly on the resistance of the dendritic membrane (Barrett and Crill, 1974b; Rall, 1959), which, in turn, depends on the density and degree of opening of ionic channels in the membrane. Since ionic channels are presumed to be most highly concentrated near synapses, and since the distributions and types of synapses and their frequencies of activation may be highly nonuniform, the resistance of dendritic membrane can be expected to be nonuniform (Barrett, 1975; Eaton, 1980). Furthermore, synaptic activity, which is responsible for opening and closing ionic channels varies from moment to moment. Spatial and temporal variations in membrane resistance may cause the effectiveness of an individual synaptic input to be quite different at one moment than at another.


Synaptic Input Reversal Potential Dendritic Segment Cortical Pyramidal Neuron Dendritic Membrane 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Barrett, J. N., 1975, Motoneuron dendrites: Role in synaptic integration, Fed. Proc. 34: 1398–1407.PubMedGoogle Scholar
  2. Barrett, J. N., and Crill, W. E., 1974a, Specific membrane properties of cat motoneurones, J. Physiol. (Loud.) 239: 301–324.Google Scholar
  3. Barrett, J. N., and Crill, W. E., 1974b, Influence of dendritic location and membrane properties on the effectiveness of synapses on cat motoneurones, J. Physiol (Lond.) 239: 325–345.Google Scholar
  4. Connors, B. W., Gutnick, M. J., and Prince, D. A., 1982, Electrophysiological properties of neocortical neurons in vitro, J. Neurophysiol. 48: 1302–1320.PubMedGoogle Scholar
  5. Eaton, D., 1980, How are the membrane properties of individual neurons related to information processing? in: Information Processing in the Nervous System ( H. M. Pinsker and W. D. Willis, Jr., eds.), Raven Press, New York, p. 39–58.Google Scholar
  6. Flatman, J. A., Schwindt, P. C., Crill, W. E., and Stafstrom, C. E., 1983, Multiple actions of N-methyl-Daspartate on cat neocortical neurons in vitro, Brain Res. 266: 169–173.PubMedCrossRefGoogle Scholar
  7. Fleshman, J. W., Segev, I, Cullheim, S., and Burke, R. E., 1983, Matching electrophysiological with morphological measurements in cat alpha-motoneurons, Soc. Neurosci. Abstr. 9: 431.Google Scholar
  8. Holmes, W. R., 1986, A continuous cable method for determining the transient potential in passive dendritic trees of known geometry, Biol.Cybernet. 55: 115–124.Google Scholar
  9. Jahnsen, H., and Llinas, R, 1984a, Electrophysiological properties, pf guinea-pig thalamic neurons: An in vitro study, J. Physiol.(Lond.) 349: 205–226.Google Scholar
  10. Jahnsen, H., and Llinas, R., 1986, Ionic basis for the electroresponsiveness and oscillatory properties of guinea-pig thalamic neurones, in vitro, J. Physiol.(Lond.) 349: 227–247.Google Scholar
  11. Krnjevic, K. Pumain, R., and Renaud, L, 1971, The mechanism of excitation by acetylcholine in the cerebral cortex, J. Physiol.(Lond.) 215: 247–268.Google Scholar
  12. Llinas, R., and Sugimori, M., 1980a, Electrophysiological properties of in vitro purkinje cell somata in mammalian cerebellar slices, J. Physiol.(Lond.) 305: 171–195.Google Scholar
  13. Llinas, R., and Sugimori, M., 1980b, Electrophysiological properties of in vitro purkinje cell dendrites in mammalian cerebellar slices, J. Physiol.(Lond.) 305: 197–213.Google Scholar
  14. Rall, W., 1959, Branching dendritic trees and motoneuron membrane resistivity, Exp. Neurol. 1: 491–527.PubMedCrossRefGoogle Scholar
  15. Sakai, M., Sakai, H., and Woody, C. D., 1978, Intracellular staining of cortical neurons by pressure microin-jection of horseradish peroxidase and recovery by core biopsy, Exp. Neurol. 58: 138–144.PubMedCrossRefGoogle Scholar
  16. Stafstrom, C. E., Schwindt, P. C., Crill, W. E., and Flatman, J. A. 1982, Membrane currents in cat neocortical neurons, in vitro, Soc. Neurosci. Abstr. 8: 413.Google Scholar
  17. Stafstrom, C. E., Schwindt, P. C., Crill, W. E., and Flatman, J. A., 1984, Properties of subthreshold response and action potential recorded in layer V neurons from cat sensorimotor cortex in vitro, J. Neurophysiol. 52: 244–263.PubMedGoogle Scholar
  18. Stafstrom, C. E., Schwindt, P. C., Chubb, M. C., and Crill, W. E., 1985, Properties of persistent sodium conductance and calcium conductance of layer V neurons from cat sensorimotor cortex in vitro, J. Neurophysiol. 53: 153–170.PubMedGoogle Scholar
  19. Woody, C. D., and Gruen, E., 1978, Characterization of electrophysiological properties of intracellularly recorded neurons in the neocortex of awake cats: A comparison of the response to injected current in spike overshoot and undershoot neurons, Brain Res. 158: 343–357.PubMedCrossRefGoogle Scholar
  20. Woody, C. D., Gruen, E., and McCarley, K., 1984, Intradendritic recordings from neurons of the motor cortex of cats, J. Neurophysiol. 51: 925–938.PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1988

Authors and Affiliations

  • William R. Holmes
    • 1
  • Charles D. Woody
    • 2
  1. 1.Mathematical Research Branch, National Institute of Diabetes and Digestive and Kidney DiseasesNational Institutes of HealthBethesdaUSA
  2. 2.Mental Retardation Research Center, Brain Research InstituteUniversity of California at Los AngelesLos AngelesUSA

Personalised recommendations