Meng Xiangying, Huguet Gemma, Rinzel John
Dynamics and Control, Beihang University, Beijing, China, Center for Neural Science, New York University, USA.
Discrete Contin Dyn Syst Ser A. 2012 Aug 1;32(8):2729-2757. doi: 10.3934/dcds.2012.32.2729.
Some neurons in the nervous system do not show repetitive firing for steady currents. For time-varying inputs, they fire once if the input rise is fast enough. This property of phasic firing is known as Type III excitability. Type III excitability has been observed in neurons in the auditory brainstem (MSO), which show strong phase-locking and accurate coincidence detection. In this paper, we consider a Hodgkin-Huxley type model (RM03) that is widely-used for phasic MSO neurons and we compare it with a modification of it, showing tonic behavior. We provide insight into the temporal processing of these neuron models by means of developing and analyzing two reduced models that reproduce qualitatively the properties of the exemplar ones. The geometric and mathematical analysis of the reduced models allows us to detect and quantify relevant features for the temporal computation such as nearness to threshold and a temporal integration window. Our results underscore the importance of Type III excitability for precise coincidence detection.
神经系统中的一些神经元对于稳定电流不会表现出重复放电。对于随时间变化的输入，如果输入上升速度足够快，它们会放电一次。这种相位性放电特性被称为III型兴奋性。在听觉脑干（MSO）的神经元中观察到了III型兴奋性，这些神经元表现出强烈的锁相和精确的重合检测。在本文中，我们考虑了一种广泛用于相位性MSO神经元的霍奇金-赫胥黎类型模型（RM03），并将其与表现出紧张性行为的该模型的一种修改版本进行比较。我们通过开发和分析两个简化模型来深入了解这些神经元模型的时间处理，这两个简化模型定性地再现了典型模型的特性。简化模型的几何和数学分析使我们能够检测和量化时间计算的相关特征，如接近阈值的程度和时间积分窗口。我们的结果强调了III型兴奋性对于精确重合检测的重要性。
