Alteration of neural action potential patterns by axonal stimulation: the importance of stimulus location
Alteration of neural action potential patterns by axonal stimulation: the importance of stimulus location
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DOI：
10.1088/1741-2560/11/5/056016
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发表时间：
2014-10-01
影响因子：
4
通讯作者：
Makowski, Nathaniel S.
中科院分区：
文献类型：
--
作者：
Crago, Patrick E.;Makowski, Nathaniel S.
Objective.周围神经的刺激通常叠加在同一轴突中正在进行的运动和感觉活动上，而没有轴突端点净动作电位训练的定量模型。Approach.我们开发了一个模型的动作电位模式引起的叠加恒定频率轴突刺激的动作电位从生理激活的神经源到达。该模型包括相互作用，由于碰撞块，重置的神经脉冲发生器，和轴突的刺激点的不应期。主要结果。动作电位放电周期的平均终点放电率和概率分布都强烈依赖于两个源的相对放电率和它们之间的部位间传导时间。当刺激速率超过神经速率时，神经动作电位不会到达终点，并且终点动作电位的速率与刺激速率相同，而与部位间传导时间无关。然而，当刺激率小于神经率，并且部位间传导时间较短时，两个率部分相加。刺激速率的增加产生终点速率的非单调增加和神经产生的动作电位的持续增加的阻滞。随着部位间传导时间的增加，频率总和减少，更多的神经动作电位被阻断。在较长的部位间传导时间，终点速率简化为神经或刺激速率的最大值。意义这项研究强调了通过低速率刺激和短的部位间传导时间来增加终点动作电位速率和保护神经信息传输的潜力。部位间传导时间可以通过用于肌肉的近端刺激部位和用于感觉末梢的远端刺激部位来减少。该模型为优化实验和设计涉及运动或感觉刺激的神经假体干预提供了基础。
Objective. Stimulation of peripheral nerves is often superimposed on ongoing motor and sensory activity in the same axons, without a quantitative model of the net action potential train at the axon endpoint. Approach. We develop a model of action potential patterns elicited by superimposing constant frequency axonal stimulation on the action potentials arriving from a physiologically activated neural source. The model includes interactions due to collision block, resetting of the neural impulse generator, and the refractory period of the axon at the point of stimulation. Main results. Both the mean endpoint firing rate and the probability distribution of the action potential firing periods depend strongly on the relative firing rates of the two sources and the intersite conduction time between them. When the stimulus rate exceeds the neural rate, neural action potentials do not reach the endpoint and the rate of endpoint action potentials is the same as the stimulus rate, regardless of the intersite conduction time. However, when the stimulus rate is less than the neural rate, and the intersite conduction time is short, the two rates partially sum. Increases in stimulus rate produce non-monotonic increases in endpoint rate and continuously increasing block of neurally generated action potentials. Rate summation is reduced and more neural action potentials are blocked as the intersite conduction time increases. At long intersite conduction times, the endpoint rate simplifies to being the maximum of either the neural or the stimulus rate. Significance. This study highlights the potential of increasing the endpoint action potential rate and preserving neural information transmission by low rate stimulation with short intersite conduction times. Intersite conduction times can be decreased with proximal stimulation sites for muscles and distal stimulation sites for sensory endings. The model provides a basis for optimizing experiments and designing neuroprosthetic interventions involving motor or sensory stimulation.