电刺激期间神经细胞单元锋电位的检测

Detecting Neuronal Unit Spikes during Electrical Stimulation Periods

大脑深部电刺激(DBS)已成功用于临床治疗帕金森等中枢神经系统疾病;但是DBS的作用机制尚无定论。为了考察电刺激期间神经细胞动作电位(即单元锋电位)发放的规律,本研究设计了一种插值法去除刺激伪迹和大幅值诱发波,并设定信号斜率的阈值来自动选定插值区的端点,尽可能缩短锋电位的不可测期(NP)。该算法用于大鼠海马CA1区正向和反向电刺激期间锋电位的分析,结果表明:它可以将紧随刺激的NP缩短约8 ms;而且与线性插值相比,样条插值对于锋电位检测的影响更小。此插值法能够有效地用于高频串刺激期间锋电位信号的检测,从而为深入研究DBS期间的神经元活动提供了一种简单实用的新方法。

Deep brain stimulation （DBS） has been used to treat disorders in clinical practice, such as Parkinson＇ s disease of central nervous system. However, the mechanisms of DBS are not clear yet. In order to investigate the changes of action potential （ i. e. , unit spike） firings of individual neurons during the periods of electrical stimulation, we designed an interpolation method to remove stimulation artifacts together with evoked potentials with large amplitudes. Thresholds of signal slope were used to determine the end points of interpolation segment thereby minimizing the non-usable period （NP） of spike detection. The method was used to analyze the spike activity during either orthodromic or antidromic stimulation of hippocampal CA1 region in rat brain. Results showed that the NP immediately following stimulation could be shortened by - 8 ms using the method. A further decrease of the influence was achieved by using spline interpolation instead of linear interpolation. The novel method can be used to detect spike signals during the periods of high frequency stimulation efficiently, providing a simple and practicable method to investigate the neuronal activity during DBS.