Kudela Pawel, Franaszczuk Piotr J, Bergey Gregory K
Department of Neurology, Johns Hopkins Epilepsy Center, Johns Hopkins University School of Medicine, Meyer 2-147, 600 North Wolfe Street, Baltimore, MD 21287, USA.
Biol Cybern. 2003 Apr;88(4):276-85. doi: 10.1007/s00422-002-0381-7.
The development of synchronous bursting in neuronal ensembles represents an important change in network behavior. To determine the influences on development of such synchronous bursting behavior we study the dynamics of small networks of sparsely connected excitatory and inhibitory neurons using numerical simulations. The synchronized bursting activities in networks evoked by background spikes are investigated. Specifically, patterns of bursting activity are examined when the balance between excitation and inhibition on neuronal inputs is varied and the fraction of inhibitory neurons in the network is changed. For quantitative comparison of bursting activities in networks, measures of the degree of synchrony are used. We demonstrate how changes in the strength of excitation on inputs of neurons can be compensated by changes in the strength of inhibition without changing the degree of synchrony in the network. The effects of changing several network parameters on the network activity are analyzed and discussed. These changes may underlie the transition of network activity from normal to potentially pathologic (e.g., epileptic) states.
神经元集群中同步爆发的发展代表了网络行为的一个重要变化。为了确定对这种同步爆发行为发展的影响，我们使用数值模拟研究了由稀疏连接的兴奋性和抑制性神经元组成的小网络的动力学。研究了背景尖峰诱发的网络中的同步爆发活动。具体而言，当神经元输入上的兴奋与抑制之间的平衡发生变化以及网络中抑制性神经元的比例改变时，检查爆发活动的模式。为了对网络中的爆发活动进行定量比较，使用了同步程度的度量。我们证明了如何通过抑制强度的变化来补偿神经元输入上兴奋强度的变化，而不改变网络中的同步程度。分析和讨论了改变几个网络参数对网络活动的影响。这些变化可能是网络活动从正常状态转变为潜在病理（例如癫痫）状态的基础。
