Jaw F S, Lin C W, Wang C Y
Center for Biomedical Engineering, College of Medicine, National Taiwan University, Taipei.
J Neurosci Methods. 1995 Nov;62(1-2):175-8. doi: 10.1016/0165-0270(95)00059-3.
In electrophysiological recording, a microcomputer-based analog-to-digital (A/D) card is an indispensable instrument for signal acquisition and analysis. In our studies, evoked responses sampled by our A/D card showed variation among different cycles. If several cycles had been averaged, the resultant waveform would have a smaller peak amplitude and a longer duration. To explain this phenomenon, a simulated sampling model of compound action potential was proposed. Our experimental data agreed very well with the prediction of the simulated model. The long and varied delay time between the external trigger and the first sampling in each cycle by our A/D card might be the main cause of such variation. This problem could not be solved by any post-sampled programming. Hence, for those electrophysiological laboratories which sampled evoked responses, to buy a new A/D card might be the most straightforward solution to the problem.
在电生理记录中，基于微型计算机的模数（A/D）卡是信号采集和分析不可或缺的仪器。在我们的研究中，由我们的A/D卡采样的诱发反应在不同周期之间表现出变化。如果对几个周期进行平均，所得波形的峰值幅度会更小，持续时间会更长。为了解释这一现象，提出了复合动作电位的模拟采样模型。我们的实验数据与模拟模型的预测非常吻合。我们的A/D卡在每个周期中外部触发与第一次采样之间漫长且变化的延迟时间可能是这种变化的主要原因。任何采样后编程都无法解决这个问题。因此，对于那些采样诱发反应的电生理实验室来说，购买一张新的A/D卡可能是解决该问题最直接的办法。
