神經在動作電位期間伴隨許多現象，除了電位的變化之外，還會伴隨著機械特性和熱力學的變化。而神經有無髓鞘包覆也會影響到神經傳導速度。目前文獻所提出的模型雖能描述膜電位變化，機械變化，或同時描述兩者。然而卻無法解釋為何具髓鞘的神經傳導速度比無髓鞘的神經傳導速度快。因此有必要建立一個神經之數值模型，利用此模型描述神經動作電位的產生、傳遞以及模擬具髓鞘神經跳躍式傳導現象。
本研究利用有限元素法建立神經數值之模型以計算動作電位期間在神經軸突傳遞的機械波，引進離子通道的機械模型，並提出機械波與動作電位的轉換機制。由神經軸突的機械波得知當細胞質的剛性較細胞皮質小時，其傳遞機械波效果最好。而細胞膜和細胞質的黏滯性對細胞膜徑向位移有影響，但對軸向應力卻無影響。神經軸突與髓鞘的交互作用為接觸時，其位移波、應力波以及傳導速度皆會增加。離子通道設為二階質量-阻尼-彈簧過阻尼系統時可以模擬出由Hodgkin–Huxley模型所得之離子通道的電壓變化。
本研究提出的模型不僅能夠解釋動作電位如何產生，所模擬出來電位變化也與實驗數據符合，也能模擬動作電位的傳遞，其在細胞膜表面產生的位移也接近實驗值，且能夠模擬具髓鞘神經的跳躍式傳導。

SUMMARY
Several physics phenomena such as membrane potential, mechanical deformation, thermodynamic changes occur during the propagation of action potential on the axons of peripheral nerve. The myelin affects the propagation speed of action potential. In recent years, new models such as Hodgkin-Huxley model and soliton model for the action potential have been proposed. Although these models can describe the action potential and the mechanical changes, the saltatory conduction still can not be explained by these model. In this thesis, the propagation of action potential is modeled as mechanical action wave propagated on the axon of nerve. A mechanical model of ion channels and transduction mechanism of mechanical wave to action potential were proposed. Finite element models of unmyelinated and myelinated axons were built and propagation of the action were simulated. The results show that, when stiffness of cytoplasm is smaller than cortex, the propagation speed are in agreement with experimental results. The viscosities of membrane and cytoplasm have no effect on radial but axial mechanical wave. When the interaction between myelin and axon is contact, the displacement, stress and conduction speed are increased compared to unmyelinated axon. The over-damped 2nd order mechanical model of ion channels could describe the transduction of stress wave to action potential at the distal end of the electro-mechanical model of axon. The model developed in this thesis can simulate not only the propagation and generation of action potential but also the saltatory conduction.

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