Experimentaland Theoretical Studies on Neural Coding

神经编码的实验和理论研究

• 批准号: 05044099
• 负责人: SATO Shunsuke
• 金额: $ 4.16万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05044099/
• 关键词: neuralcoding; Hodgkin-Huxleyequation; Bonhoeffer-vander Polequation; Cantorfunction-likegraph; apacemaker neuron; isochron; phase transtioncurve; bifurcationdiagrams; a modifiedIRC model; ペースメーカ細胞; 神経振動子; 刺激応答特性; 分岐現象; カオス; 大域的応答特性

For the study of information processing mechanisms in the nervous system, it is crucial to understand how events from the outer world and their relationships are encoded. Much work has been done along these lines. A report on neural coding was published in the 60's by Perkel et al.and they introduced several physiological processes for information transmission in single cells and also the candidate codes by which the nervous system sends and retrieves information. Takahashi et al.stimulated the squid giant axon by periodic current stimuli and measured the corresponding membrane voltage. Segundo et al.observed how the firing patterns and frequency of a single cell were modulated when it received periodic inhibitory inputs. Harmon's model was an electric analog mimicking single neuron activities. The Hodgkin-Huxley(abbreviated by H-H)and Nagumo equations were mathematical models. Perkel carried out computer simulations of pacemaker neurons of Aplysia driven by excitatory or inhibitory sy … More naptic inputs. The H-H equation were used to clarify the underlying mechanisms of the membrane excitations related to the periodic and chaotic responses of single neurons. The Bonhoeffer-van der Pol(BVP)model is used to simulate the neural behaviors since it provides a simpler model.All these publications are relevant to neural coding, namely implications of an individual neuron's dynamics and nonlinearlity for its computational properties.Results obtained in the present research program on neural coding are as follows :1)The characteristics of the BVP neuron model response to periodic pulse stimulus are investigated. Temporal patterns of the output of the model are analyzed as a function of the stimulus intensity and period. The BVP model exhibits the same chaotic behavior and a Cantor function like graph of the response frequency(mean frequency)as in electrophysiological experiments. This shows that the BVP model describes the complicated response characteristics of the neuron at least qualitatively.2)A recent investigation of the influence of periodic inhibitory trains on a crayfish pacemaker neuron showed not only well-known locked periodic responses but also intermittent, messy and hopping responses. This communication studies the responses of the BVP model with self-sustained oscillation when exposed to periodic pulse trains inputs. The analysis is similar to that used in crayfish and reveals interesting features, both comparable and complementary to those seen in the living preparation.3)The BVP oscillator is a valuable dynamical system model of pacemaker neurons. Isochron, phase transition curves(PTC)and two dimensional bifurcation diagrams served to analyze the neuron's response to periodic pulse stimuli. Responses are described and explained in terms of the nonlinear dynamical system theory. An important issue in the generation of spikes by pacemaker neurons is the existence of both slow and fast dynamics in the state point's trajectory in the phase plane. It is this feature in particular that makes the BVP oscillator a faithful model of living pacemaker neurons. Comparison of the model's responses with those of a living pacemaker was based also on return maps of interspike intervals. Analyzed in detail were the complex discharges called 'stammering'which involve interspike intervals that arise unexpectably and exhibit histgrams with several modes separated by the equal intervals.4)A simple mathematical model of living pacemaker neurons is proposed. The model has a unit circle limit cycle and radial isochrons and the state point moves slowly in one region and fast in the remaining region ; regions can correspond to the subthreshold activity and to the action potentials of pacemaker neurons, respectively. The global bifurcation structure when driven by periodic pulse trains was investigated using one-dimensional maps(PTC), two-dimensional bifurcation diagrams, and skeletons involving stimulus period and intensity. The existence of both the slow and the fast dynamics has a critical influence on the global bifurcation structure of the oscillator when stimulated periodically. Less

对于神经系统中信息处理机制的研究，了解来自外部世界的事件及其关系是如何编码的至关重要。在这方面已经做了沿着许多工作。Perkel等人在60年代发表了关于神经编码的报告，他们介绍了单细胞中信息传输的几种生理过程以及神经系统发送和检索信息的候选代码。Takahashi等通过周期性电流刺激鱿鱼巨轴突，并测量相应的膜电压。Segundo等人观察了当单个细胞接受周期性抑制性输入时，它的放电模式和频率是如何被调制的。哈蒙的模型是一种模拟单个神经元活动的电模拟。Hodgkin-Huxley（缩写为H-H）和Nagumo方程是数学模型。Perkel对兴奋性或抑制性系统驱动的失智症起搏神经元进行了计算机模拟。 ...更多信息 naptic输入利用H-H方程阐明了与单神经元周期性和混沌性反应相关的膜兴奋机制。Bonhoven-van der Pol（BVP）模型是一种简单的神经行为模拟模型，这些文献都与神经编码有关，即单个神经元的动力学和非线性对其计算特性的影响，本文主要研究了BVP神经元模型对周期脉冲刺激的响应特性，并对BVP神经元模型的计算特性进行了研究。模型输出的时间模式作为刺激强度和周期的函数进行分析。BVP模型表现出与电生理实验中相同的混沌行为和类似Cantor函数的响应频率（平均频率）图。这表明BVP模型至少定性地描述了神经元的复杂反应特性。2）最近的一项关于周期性抑制列车对小龙虾起搏神经元影响的研究表明，不仅有众所周知的锁定周期反应，而且还有间歇性、杂乱和跳跃反应。本文研究了具有自持振荡的边值问题模型在周期脉冲串输入下的响应。该分析类似于在小龙虾中使用的分析，并且揭示了有趣的特征，与在活体动物中看到的特征具有可比性和互补性。3）BVP振荡器是起搏神经元的有价值的动力系统模型。用等时线、相变曲线和二维分叉图分析了神经元对周期性脉冲刺激的反应。响应描述和解释的非线性动力系统理论。起搏神经元产生尖峰的一个重要问题是相平面中状态点的轨迹中存在慢动力学和快动力学。正是这一特点使得BVP振荡器成为了一个真实的起搏神经元模型。模型的反应与生活起搏器的比较也是基于返回地图的interspike间隔。详细分析了称为“口吃”的复杂放电，其中包括意外出现的峰间期，并显示出由相等间隔分隔的几个模式的直方图。4）提出了一个简单的活起搏神经元的数学模型。该模型有一个单位圆极限环和径向等时线和状态点移动缓慢，在一个区域和快速在其余区域;区域可以对应于阈下活动和起搏神经元的动作电位，分别。使用一维映射（PTC），二维分叉图，和骨架涉及刺激周期和强度驱动的周期脉冲序列时的全局分叉结构进行了研究。当周期激励时，慢动力学和快动力学的同时存在对系统的全局分岔结构有着重要的影响。少

项目成果

T.Nomura,S.Sato,S.Doi,J.P.Segundo,M.D.Stiber:"Global bifurcation structure of a Bonhoeffer van der Pol oscillator driven by periodic pulse trains.Comparison with data from an inhibitory synapse" Biological Cybernetics. 72. 55-67 (1994)

T.Nomura、S.Sato、S.Doi、J.P.Segundo、M.D.Stiber：“由周期性脉冲序列驱动的 Bonhoeffer van der Pol 振荡器的全局分叉结构。与抑制性突触的数据比较”生物控制论。

S.Doi and S.Sato: "The global bifurcation structure of the BVP neuronal model driven by periodic pulse trains" Mathematical Biosciences. (in press). (1995)

S.Doi 和 S.Sato：“周期性脉冲序列驱动的 BVP 神经元模型的全局分叉结构”数学生物科学。

山脇伸行,佐藤俊輔,土居伸二: "ハードウェアニューロンモデルの周期パルス入力に対する応答特性" MEとバイオサイバネティックス研究会. MBE93-25. 113-120 (1993)

Nobuyuki Yamawaki、Shunsuke Sato、Shinji Doi：“硬件神经元模型对周期性脉冲输入的响应特性”ME 和生物控制论 MBE93-25 (1993)。

高畑友昭,野村泰伸,土居伸二,佐藤俊輔: "小規模ネットワークによるCPG(中枢パターン発生器)の構成と周期入力に対する応答" 信学技報,MEとバイオサイバネティックス研究会. MBE94-3. 17-24 (1994)

Tomoaki Takahata、Yasunobu Nomura、Shinji Doi、Shunsuke Sato：“使用小规模网络配置 CPG（中央模式生成器）并响应周期性输入”IEICE 技术报告，ME 和生物控制论 MBE94-3。 (1994)

Shunsuke Sato: "Wiener and other analyses of nonlinear systems and signals and their applications to biology" Frontier in Medical and Biological Engineering. 6. 1-35 (1994)

Shunsuke Sato：“维纳和其他非线性系统和信号的分析及其在生物学中的应用”医学和生物工程前沿。