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  • 1 Tokushima Bunri University Laboratory of Pharmaceutics, Kagawa School of Pharmaceutical Sciences 1314-1, Shido, Sanuki Kagawa 769-2193 Japan
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Pyramidal cells in the electrosensory lateral line lobe (ELL) of weakly electric fish produce burst discharge. A Hodgkin-Huxley-type model, called ghostburster, consisting of two compartments (soma and dendrite) reproduces ELL pyramidal cell bursting observed in vitro. A previous study analyzed the ghostburster by treating Is and gDr,d as bifurcation parameters (Is: current injected into the somatic compartment and gDr,d: maximal conductance of the delayed rectifying potassium current in the dendritic compartment) and indicated that when both Is and gDr,d are set at particular values, the ghostburster shows a codimension-two bifurcation at which both saddle-node bifurcation of fixed points and saddle-node bifurcation of limit cycles occur simultaneously. In the present study, the ghostburster was investigated to clarify the bursting that occurred at gDr,d values smaller than that at the codimension-two bifurcation. Based on the number of spikes per burst, various burst patterns were observed depending on the (Is, gDr,d) values. Depending on the (Is, gDr,d) values, the burst trajectory in a phase space of the ghostburster showed either a high or a low degree of periodicity. Compared to the previous study, the present findings contribute to a more detailed understanding of ghostburster bursting.

  • Doiron, B., Laing, C., Longtin, A., Maler, L. (2002) Ghostbursting: A novel neuronal burst mechanism. J. Comput. Neurosci. 12, 5–25.

    Maler L. , 'Ghostbursting: A novel neuronal burst mechanism ' (2002 ) 12 J. Comput. Neurosci. : 5 -25.

    • Search Google Scholar
  • Gabbiani, F., Metzner, W. (1999) Encoding and processing of sensory information in neuronal spike trains. J. Exp. Biol. 202, 1267–1279.

    Metzner W. , 'Encoding and processing of sensory information in neuronal spike trains ' (1999 ) 202 J. Exp. Biol. : 1267 -1279.

    • Search Google Scholar
  • Gabbiani, F., Metzner, W., Wessel, R., Koch, C. (1996) From stimulus encoding to feature extraction in weakly electric fish. Nature 384, 564–567.

    Koch C. , 'From stimulus encoding to feature extraction in weakly electric fish ' (1996 ) 384 Nature : 564 -567.

    • Search Google Scholar
  • Heiligenberg, W. (1991) Neural Nets in Electric Fish. MIT Press, Cambridge, MA.

    Heiligenberg W. , '', in Neural Nets in Electric Fish , (1991 ) -.

  • Lemon, N., Turner, R. W. (2000) Conditional spike backpropagation generates burst discharge in a sensory neuron. J. Neurophysiol. 84, 1519–1530.

    Turner R. W. , 'Conditional spike backpropagation generates burst discharge in a sensory neuron ' (2000 ) 84 J. Neurophysiol. : 1519 -1530.

    • Search Google Scholar
  • Metzner, W., Koch, C., Wessel, R., Gabbiani, F. (1998) Feature extraction by burst-like spike patterns in multiple sensory maps. J. Neurosci. 15, 2283–2300.

    Gabbiani F. , 'Feature extraction by burst-like spike patterns in multiple sensory maps ' (1998 ) 15 J. Neurosci. : 2283 -2300.

    • Search Google Scholar
  • Rashid, A. J., Morales, E., Turner, R. W., Dunn, R. J. (2001) The contribution of dendritic Kv3 K+ channels to burst threshold in a sensory neuron. J. Neurosci. 21, 125–135.

    Dunn R. J. , 'The contribution of dendritic Kv3 K+ channels to burst threshold in a sensory neuron ' (2001 ) 21 J. Neurosci. : 125 -135.

    • Search Google Scholar
  • Turner, R. W., Maler, L. (1999) Oscillatory and burst discharge in the apteronotid electrosensory lateral line lobe. J. Exp. Biol. 202, 1255–1265.

    Maler L. , 'Oscillatory and burst discharge in the apteronotid electrosensory lateral line lobe ' (1999 ) 202 J. Exp. Biol. : 1255 -1265.

    • Search Google Scholar
  • Turner, R. W., Maler, L., Deerinck, T., Levinson, S. R., Ellisman, M. (1994) TTX-sensitive dendritic sodium channels underlie oscillatory discharge in a vertebrate sensory neuron. J. Neurosci. 14, 6453–6471.

    Ellisman M. , 'TTX-sensitive dendritic sodium channels underlie oscillatory discharge in a vertebrate sensory neuron ' (1994 ) 14 J. Neurosci. : 6453 -6471.

    • Search Google Scholar