Department of Signal Processing, Tampere University of Technology Tampere, Finland.
Front Comput Neurosci. 2011 Jun 1;5:26. doi: 10.3389/fncom.2011.00026. eCollection 2011.
Neuronal networks exhibit a wide diversity of structures, which contributes to the diversity of the dynamics therein. The presented work applies an information theoretic framework to simultaneously analyze structure and dynamics in neuronal networks. Information diversity within the structure and dynamics of a neuronal network is studied using the normalized compression distance. To describe the structure, a scheme for generating distance-dependent networks with identical in-degree distribution but variable strength of dependence on distance is presented. The resulting network structure classes possess differing path length and clustering coefficient distributions. In parallel, comparable realistic neuronal networks are generated with NETMORPH simulator and similar analysis is done on them. To describe the dynamics, network spike trains are simulated using different network structures and their bursting behaviors are analyzed. For the simulation of the network activity the Izhikevich model of spiking neurons is used together with the Tsodyks model of dynamical synapses. We show that the structure of the simulated neuronal networks affects the spontaneous bursting activity when measured with bursting frequency and a set of intraburst measures: the more locally connected networks produce more and longer bursts than the more random networks. The information diversity of the structure of a network is greatest in the most locally connected networks, smallest in random networks, and somewhere in between in the networks between order and disorder. As for the dynamics, the most locally connected networks and some of the in-between networks produce the most complex intraburst spike trains. The same result also holds for sparser of the two considered network densities in the case of full spike trains.
神经网络表现出广泛的结构多样性,这有助于其中的动力学多样性。本工作应用信息论框架同时分析神经元网络中的结构和动力学。使用归一化压缩距离研究神经元网络中结构和动力学的信息多样性。为了描述结构,提出了一种生成具有相同入度分布但距离依赖性强度可变的距离相关网络的方案。生成的网络结构类具有不同的路径长度和聚类系数分布。同时,使用 NETMORPH 模拟器生成可比的现实神经元网络,并对它们进行类似的分析。为了描述动力学,使用不同的网络结构模拟网络尖峰训练,并对它们进行爆发行为分析。对于网络活动的模拟,使用尖峰神经元的 Izhikevich 模型和动态突触的 Tsodyks 模型。我们表明,模拟神经元网络的结构会影响自发爆发活动,其测量指标包括爆发频率和一组爆发内指标:连接越紧密的网络比随机网络产生更多和更长的爆发。网络结构的信息多样性在连接最紧密的网络中最大,在随机网络中最小,在有序和无序之间的网络中则处于两者之间。对于动力学,连接最紧密的网络和一些处于两者之间的网络产生最复杂的爆发内尖峰训练。在两种考虑的网络密度中,稀疏的网络密度也会产生最复杂的全尖峰训练。