听觉诱发电位的时变滤波叠加

多数诱发电位具有突出的“时变”特性:它们属瞬态反应,在反应前、反应中、反应后各个阶段,电活动的频谱都不断在变化,时变滤波的技术要点:使滤波参数根据电反应的瞬时特性而变,从而更有效地提取有用信号,提高信噪比、缩短操作时间。本文对一般叠加平均处理和时变滤波叠加在动物和人各种听觉诱发电位的信噪比进行了比较。结果显示时变滤波叠加的诱发电位信噪比明显提高,使用时变滤波叠加处理,能达到背景噪声小的效果和反应波形清晰的优点。在大多数情况下,叠加次数可相应地减少,使听觉诱发电位测试效率有所提高。

Time-Varying Filtering Average of Auditory Evoked Potential

Most of the evoked potentials have time varying characteristic. The response is transient and its response spectral is varying during the response period. The key point of the time - varying filtering method is that the filter varies as the response changes, so it can get the signal effectively and raise the signal to noise ratio. In present report, we compared these two methods, and our result shows that the raise of signal to noise ratio is significant by using the time - varying filtering method. This technique can reduce the background noise and repetitions, and the waveform is clearer than that of usual average.