高刺激率听觉诱发电位去卷积技术的有效性研究

Comparison of the Efficiency of Techniques for Deconvolving Auditory-evoked Potentials with High Rate Stimulation

听觉诱发电位(auditory evoked potentials,AEPs)的高刺激率方案在相同记录时间内可提供更多的刺激,目前可用一些较成熟的基于去卷积技术的方法,将其重叠的暂态反应恢复出来,从而在基础和临床应用领域拓展了传统技术的研究范畴。本文研究了高刺激率条件下应用不同方法还原诱发反应的有效性,即去卷积技术是否可以提高恢复信号的质量。分别应用常规的叠加平均方法、连续循环平均去卷积(continuous loop averaging deconvolu-tion,CLAD)方法和最大长序列(maximum length sequence,MLS)方法还原听觉诱发电位,以常规方案为基准,通过计算理想反应与三种方法还原反应间的相关系数及欧氏距离,评估在相同记录时间条件下高刺激率方案还原信号的质量。结果表明,MLS方案比常规方案恢复信号质量略有提高,CLAD方法恢复信号的质量则较低,提示实际应用中反而需要更多的记录时间;而当存在重叠反应的情况下,采用增加刺激速率的做法不能作为一种提高记录效率的手段。

In some auditory evoked potential （AEP） examinations,high rate stimulation paradigms deliver more stimuli with the same period of time,which might lead to overlapping responses. At present,several established techniques can be proposed to address such problem,thus the research scope in both scientific and clinical applications is expanded. In this study,the restoring efficiency of evoked responses is investigated using a simulation strategy. We examined the AEPs derived from three paradigms— conventional ensemble averaging,continuous loop averaging deconvolution （CLAD） and maximum length sequence （MLS）. Their performances were evaluated by correlation coefficients and Euclidean distances between ideal and the derived responses. We found that MLS can only slightly enhance the performance at the cost of larger stimulus jitter and much more stimulus numbers; while CLAD method with lower jittering even degenerates the quality,suggesting that,in practical use,the recording efficiency will not be significantly improved by simply using high rate stimulation with overlapping responses introduced.