定量分析神经元锋电位与局部场电位锁相关系的新方法  

A Novel Method for the Quantitative Analysis of Phase-locking Relationship between Neuronal Spikes and Local Field Potentials

作　　者：吴蕴蕴 封洲燕[1] 郑晓静[1] 

机构地区：[1]浙江大学生物医学工程与仪器科学学院生物医学工程教育部重点实验室,杭州310027

出　　处：《生物医学工程学杂志》2014年第1期172-180,共9页Journal of Biomedical Engineering

基　　金：国家自然科学基金资助项目(30970753)

摘　　要：神经元动作电位(锋电位)的发放与局部场电位(LFP)节律之间的锁相关系反映了重要的神经编码信息,但目前的分析方法只能判断有无锁相性,而不能定量区别各种锁相性的强弱。本文利用锋电位触发的叠加平均(STA)信号,以STA信号与原始LFP信号的功率百分比值φ为指标,来评价这种锁相性的强弱。大鼠海马CA1区的实验数据以及仿真数据的验证结果均表明,指标φ与锁相性强弱之间存在单调关系,它能够提供有效的界值来区分是否锁相。由于计算该指标时无需事先滤波,它可以避免传统的区间统计法中人为限定LFP频率所造成的不利影响,为研究大脑神经信息编码的机制提供一种新的定量方法。The phase locking relationship between the firings of neuronal action potentials （i.e. , spikes） and the os cillations of local field potentials （I.FP） reflects important neural coding information. However, the present analysis methods can only determine whether there has phase-locking, but not the different strengths among various types of phase-locking. In the present paper, we used spike-triggered average （STA） signals and the percentage ratio （named φ） of the STA power to the power of original LFP as an index to evaluate the strengths of phase locking. Experimen tal recordings obtained from rat hippocampal CA1 region as well as simulation data were used to evaluate the method. The results showed that the index φ changed monotonically as a function of the strength of phase-locking, and it could provide an effective critical value to divide phase locking from non-phase locking. Because the calculation of the index does not need pre-filtering, it can avoid the unwanted influences caused by intentionally limiting the frequencies of I.FP oscillations such as in the traditional bin statistical method. Therefore, the index φ provides a novel method to investigate the mechanisms underlying neuronal coding in brain.

关 键 词：锋电位 局部场电位 锋电位触发的叠加平均 锁相 圆形统计学 

分 类 号：R310[医药卫生—基础医学]