A Critique of Modeling Population Responses for Mammalian Central Neurons
We must still be extremely cautious in accepting the conclusions reached by modeling the responses of neurons in the central mammalian nervous system. Although we know a great deal about the properties of mammalian central neurons, very little quantitative information is available. For example, although the passive membrane properties of motoneurons have been analyzed in great detail (Rall, 1977), there are now new experiments suggesting that the estimates of membrane resistivity made a decade ago (Barrett and Crill, 1974) may be too low. Experimental results from Robert Burke’s laboratory are best explained by nonuniform passive properties over the soma and dendritic tree (Fleshman et al., 1982; Rall, 1982). The point is that we do not even have reliable quantitative values for these relatively simple linear properties of central neurons.
Unable to display preview. Download preview PDF.
- Barrett, E. F., Barrett, J. N., and Crill W. E., 1980, Voltage-sensitive outward currents in cat motoneurones, J. Physiol. (London) 304: 251–276.Google Scholar
- Barrett, J. N. and Crill, W. E., 1974, Specific membrane properties of cat motoneurons, J. Physiol. (London) 239: 301–324.Google Scholar
- Barrett, J. N. and Crill, W. E., 1980, Voltage clamp of cat motoneurone somata: properties of a fast inward current, J. Physiol. (London) 304: 231–249.Google Scholar
- Brown, D. A. and Griffith, W. H., 1983, Persistent slow inward calcium current in voltage-clamped hippocampal neurones of guinea-pig, J. Physiol. (London) 337: 303–320.Google Scholar
- Conners, B. W., Gutnick, M. J., and Prince, D. A., 1982, Electrophysiological properties of neocortical neurons in vitro, J. Neurophysiol. 48: 1302–1320.Google Scholar
- Curtis, D. R. and Eccles, J. C., 1960, Synaptic action during and after repetitive stimulation, J. Physiol. (London) 150: 314–398.Google Scholar
- Dingledine, R., 1983, N-methyl aspartate activates voltage-dependent calcium conductance in rat hip-pocampal pyramidal cells, J. Physiol. (London) 343: 385–405.Google Scholar
- Fleshman, J. W., Burke, R. E., Glenn, L. L., Lev Tov, A., and Miller J. P., 1982, Cell size and specific membrane resistivity of type-identified cat motoneurons: morphological, physiological and modeling studies, Abstr. Soc. Neurosci. 8: 414.Google Scholar
- Hodgkin, A. L. and Huxley, A. F., 1952, Currents carried by sodium and potassium ions through the membrane of giant axon of Loligo, J. Physiol. (London) 116: 449–472.Google Scholar
- Llinas, R. and Sugamori, M., 1980, Electrophysiologic properties of in vitro purkinje cell somata in mammalian cerebellar slices, J. Physiol. (London) 305: 171–195.Google Scholar
- Rall, W., 1977, Core conductor theory and cable properties of neurons, in: Handbook of Physiology, Volume 1 ( E. Kandel, ed.), American Physiological Society, Bethesda, pp. 39–98.Google Scholar
- Rall, W., 1982, Theoretical models which increase Rm with dendritic distance help fit lower value of Cm, Abstr. Soc. Neurosci. 8: 414.Google Scholar
- Schwindt, P. C. and Crill, W. E., 1980, Properties of a persistent inward current normal and TEA- injected motoneurons, J. Neurophysiol. 43: 17000–1724.Google Scholar