首页 | 本学科首页   官方微博 | 高级检索  
   检索      


Ghostbursting: A Novel Neuronal Burst Mechanism
Authors:Brent Doiron  Carlo Laing  André Longtin  Leonard Maler
Institution:(1) Physics Department, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario, Canada, K1N 6N5;(2) Department of Cellular and Molecular Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Canada, K1H 8M5
Abstract:Pyramidal cells in the electrosensory lateral line lobe (ELL) of weakly electric fish have been observed to produce high-frequency burst discharge with constant depolarizing current (Turner et al., 1994). We present a two-compartment model of an ELL pyramidal cell that produces burst discharges similar to those seen in experiments. The burst mechanism involves a slowly changing interaction between the somatic and dendritic action potentials. Burst termination occurs when the trajectory of the system is reinjected in phase space near the ldquoghostrdquo of a saddle-node bifurcation of fixed points. The burst trajectory reinjection is studied using quasi-static bifurcation theory, that shows a period doubling transition in the fast subsystem as the cause of burst termination. As the applied depolarization is increased, the model exhibits first resting, then tonic firing, and finally chaotic bursting behavior, in contrast with many other burst models. The transition between tonic firing and burst firing is due to a saddle-node bifurcation of limit cycles. Analysis of this bifurcation shows that the route to chaos in these neurons is type I intermittency, and we present experimental analysis of ELL pyramidal cell burst trains that support this model prediction. By varying parameters in a way that changes the positions of both saddle-node bifurcations in parameter space, we produce a wide gallery of burst patterns, which span a significant range of burst time scales.
Keywords:bursting  electric fish  compartmental model  backpropagation  pyramidal cell
本文献已被 PubMed SpringerLink 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号