极低频外电场作用下神经元网络适应性的研究

发布时间：2018-05-16 00:38

本文选题：放电频率适应性 + 外电场　；参考：《天津大学》2012年硕士论文

【摘要】：神经系统是复杂的非线性系统，神经元是其基本单元。放电频率适应性是神经元动态特性的一个显著方面，在神经信息处理过程中起着重要的作用。外部电场会改变神经系统的动态行为，影响神经系统信息的产生和传导。首先，建立外电场作用下单神经元模型，通过数值分析得到了膜电位变化曲线、放电频率曲线和随输入变化的初始放电频率曲线；通过ISI相关性分析，发现直流外电场幅值越小时，单神经元模型有较好的适应性；交流外电场刺激下，，当交流外电场的幅值较小、频率较大时，单神经元模型表现出良好的适应性。其次，构建了两个耦合神经元的数学模型，通过数值分析发现当刺激信号较大时，两个耦合神经元模型表现出同步现象。根据得到的放电频率曲线和分析ISI相关性，发现外电场对两个耦合神经元模型的适应性的影响。最后，本文采用Strogatz和Watts提出的随机重连方法构建了小世界网络，并得到了放电频率曲线；通过对放电频率进行分析，发现小世界网络模型中的参数重连概率和神经元数目对模型的适应性不会产生明显影响，而耦合强度g会对神经元网络的适应性产生明显的变化。通过选择合适的参数，发现对于外电场的幅值和频率作用规律，小世界网络模型表现良好适应性时与单神经元模型和两个耦合神经元模型是相同的。本文的研究结果揭示了外电场的幅值和频率对神经元及神经元网络适应性的作用规律，这有助于探寻外电场对生物神经系统的影响和神经系统疾病的致病机理。
[Abstract]:The nervous system is a complex nonlinear system, and the neuron is its basic unit. The adaptation of discharge frequency is a significant aspect of the dynamic characteristics of neurons and plays an important role in the process of neural information processing. External electric field will change the dynamic behavior of nervous system and affect the generation and transmission of nervous system information. First of all, the model of outer electric field sending order neuron is established, and the membrane potential curve, discharge frequency curve and initial discharge frequency curve with input are obtained by numerical analysis. It is found that the smaller the amplitude of DC external electric field, the better the adaptability of single neuron model, and the better adaptability of single neuron model is when the amplitude of AC external electric field is small and the frequency of AC external electric field is larger. Secondly, the mathematical model of two coupling neurons is constructed. The numerical analysis shows that the two coupled neuron models exhibit synchronization phenomenon when the stimulus signal is large. According to the discharge frequency curve and the analysis of ISI correlation, the influence of external electric field on the adaptability of the two coupled neuron models was found. Finally, the small world network is constructed by using the random reconnection method proposed by Strogatz and Watts, and the discharge frequency curve is obtained, and the discharge frequency is analyzed. It is found that the probability of parameter reconnection and the number of neurons in the small-world network model have no significant effect on the adaptability of the model, but the coupling strength g will have a significant change on the adaptability of the neural network. By selecting appropriate parameters, it is found that the small-world network model is the same as the single neuron model and two coupled neuron models when the small world network model exhibits good adaptability to the amplitude and frequency of the external electric field. The results of this paper reveal the effects of the amplitude and frequency of external electric field on the adaptation of neurons and neural networks, which is helpful to explore the effects of external electric fields on biological nervous system and the pathogenesis of nervous system diseases.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R338

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