Crook S M, Ermentrout G B, Bower J M
Center for Computational Biology, Montana State University, Bozeman 59717, USA.
J Comput Neurosci. 1998 Jul;5(3):315-29. doi: 10.1023/a:1008839112707.
We explore the influence of synaptic location and form on the behavior of networks of coupled cortical oscillators. First, we develop a model of two coupled somatic oscillators that includes passive dendritic cables. Using a phase model approach, we show that the synchronous solution can change from a stable solution to an unstable one as the cable lengthens and the synaptic position moves further from the soma. We confirm this prediction using a system of coupled compartmental models. We also demonstrate that when the synchronous solution becomes unstable, a bifurcation occurs and a pair of asynchronous stable solutions appear, causing a phase lag between the cells in the system. Then using a variety of coupling functions and different synaptic positions, we show that distal connections and broad synaptic time courses encourage phase lags that can be reduced, eliminated, or enhanced by the presence of active currents in the dendrite. This mechanism may appear in neural systems where proximal connections could be used to encourage synchrony, and distal connections and broad synaptic time courses could be used to produce phase lags that can be modulated by active currents.
我们探究了突触位置和形态对耦合皮质振荡器网络行为的影响。首先，我们构建了一个包含被动树突电缆的两个耦合体细胞振荡器模型。使用相位模型方法，我们表明随着电缆长度增加以及突触位置远离胞体，同步解可从稳定解转变为不稳定解。我们使用耦合房室模型系统证实了这一预测。我们还证明，当同步解变得不稳定时，会发生分岔并出现一对异步稳定解，从而导致系统中细胞之间出现相位滞后。然后，使用各种耦合函数和不同突触位置，我们表明远端连接和宽泛的突触时间进程会促使相位滞后，而树突中主动电流的存在可减少、消除或增强这种相位滞后。这种机制可能出现在神经系统中，其中近端连接可用于促进同步，而远端连接和宽泛的突触时间进程可用于产生可由主动电流调节的相位滞后。
