Electrical stimulation of nerve fibers is used as a therapeutic tool to treat neurophysiological disorders. Despite efforts to model the effects of stimulation, its underlying mechanisms remain unclear. Current mechanistic models quantify the effects that the electrical field produces near the fiber but do not capture interactions between action potentials (APs) initiated by stimulus and APs initiated by underlying physiological activity. In this study, we aim to quantify the effects of stimulation frequency and fiber diameter on AP interactions involving collisions and loss of excitability. We constructed a mechanistic model of a myelinated nerve fiber receiving two inputs: the underlying physiological activity at the terminal end of the fiber, and an external stimulus applied to the middle of the fiber. We define conduction reliability as the percentage of physiological APs that make it to the somatic end of the nerve fiber. At low input frequencies, conduction reliability is greater than 95% and decreases with increasing frequency due to an increase in AP interactions. Conduction reliability is less sensitive to fiber diameter and only decreases slightly with increasing fiber diameter. Finally, both the number and type of AP interactions significantly vary with both input frequencies and fiber diameter. Modeling the interactions between APs initiated by stimulus and APs initiated by underlying physiological activity in a nerve fiber opens opportunities towards understanding mechanisms of electrical stimulation therapies.

中文翻译：

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模拟哺乳动物神经纤维中刺激与生理诱导的AP之间的相互作用：取决于频率和纤维直径。

神经纤维的电刺激被用作治疗神经生理疾病的治疗工具。尽管努力模拟刺激效果，但其潜在机制仍不清楚。当前的力学模型可以量化电场在纤维附近产生的影响，但不能捕获刺激引起的动作电位（AP）与基础生理活动引起的AP之间的相互作用。在这项研究中，我们旨在量化刺激频率和纤维直径对涉及碰撞和兴奋性丧失的AP相互作用的影响。我们构建了一个有髓神经纤维的机械模型，该模型接收两个输入：纤维末端的潜在生理活动，以及对纤维中间施加的外部刺激。我们将传导可靠性定义为使其到达神经纤维体末端的生理学AP的百分比。在低输入频率下，传导可靠性大于95％，并且由于AP交互作用的增加而随频率增加而降低。传导可靠性对纤维直径不太敏感，并且仅随着纤维直径的增加而略有降低。最后，AP相互作用的数量和类型都随输入频率和光纤直径而显着变化。对由刺激引发的AP和由神经纤维中潜在的生理活动引发的AP之间的相互作用进行建模，为了解电刺激疗法的机理提供了机会。传导可靠性大于95％，并且由于AP交互作用的增加而随频率增加而降低。传导可靠性对纤维直径不太敏感，并且仅随着纤维直径的增加而略有降低。最后，AP相互作用的数量和类型都随输入频率和光纤直径而显着变化。对由刺激引发的AP和由神经纤维中潜在的生理活动引发的AP之间的相互作用进行建模，为了解电刺激疗法的机理提供了机会。传导可靠性大于95％，并且由于AP交互作用的增加而随频率增加而降低。传导可靠性对纤维直径不太敏感，并且仅随着纤维直径的增加而略有降低。最后，AP相互作用的数量和类型都随输入频率和光纤直径而显着变化。对由刺激引发的AP和由神经纤维中潜在的生理活动引发的AP之间的相互作用进行建模，为了解电刺激疗法的机理提供了机会。AP交互的数量和类型都随输入频率和光纤直径而显着变化。对由刺激引发的AP和由神经纤维中潜在的生理活动引发的AP之间的相互作用进行建模，为理解电刺激疗法的机理提供了机会。AP交互的数量和类型都随输入频率和光纤直径而显着变化。对由刺激引发的AP和由神经纤维中潜在的生理活动引发的AP之间的相互作用进行建模，为了解电刺激疗法的机理提供了机会。