CAJ | 학술논문

目的：为获得电信号刺激神经纤维时的动作电位，本文设计了一种电诱发复合动作电位测量系统，解决了诱发动作电位的精确采集问题，有效去除了本底噪声的影响。方法分析了范围在十几微伏的电诱发复合动作电位到几十毫伏电极电位测量时存在的难点，以及一个测量系统正常工作时需要满足的测量放大器共模容限和差模容限及电流源电压容限问题。基于此，本文提出采用3级运算放大器级联的方式实现诱发动作电位的采集。系统主要由3级级联放大器、自动零点调整环节和基准电压部分组成，实现对弱信号的放大、消除本底噪声和提供过压保护。结果采用本文设计的系统，测量得到11 mV 的蛙类坐骨神经干复合动作电位和17μV 的豚鼠耳蜗电诱发复合动作电位，验证了本系统可有效测量各种诱发电位。结论采用3级放大器级联的方式和自动零点跟踪方式解决了微弱信号的有效放大和精确采集技术，为进一步研究通过电信号直接刺激神经纤维所产生的动作电位的特性提供可靠的测量手段。
목적：위획득전신호자격신경섬유시적동작전위，본문설계료일충전유발복합동작전위측량계통，해결료유발동작전위적정학채집문제，유효거제료본저조성적영향。방법분석료범위재십궤미복적전유발복합동작전위도궤십호복전겁전위측량시존재적난점，이급일개측량계통정상공작시수요만족적측량방대기공모용한화차모용한급전류원전압용한문제。기우차，본문제출채용3급운산방대기급련적방식실현유발동작전위적채집。계통주요유3급급련방대기、자동영점조정배절화기준전압부분조성，실현대약신호적방대、소제본저조성화제공과압보호。결과채용본문설계적계통，측량득도11 mV 적와류좌골신경간복합동작전위화17μV 적돈서이와전유발복합동작전위，험증료본계통가유효측량각충유발전위。결론채용3급방대기급련적방식화자동영점근종방식해결료미약신호적유효방대화정학채집기술，위진일보연구통과전신호직접자격신경섬유소산생적동작전위적특성제공가고적측량수단。
Objective When the nerve fiber is stimulated by the electrical pulse,there is an evoked compound action potential which indicates the synchronism property of the nerve fiber. In order to obtain the precise action potential,a measuring system of evoked compound action potential is presented in this paper. The system can collect the compound action potential precisely and eliminate the effect of ground noise. Methods Firstly,we analyzed the difficulty in the measurement of the compound action potential which ranged from μV level to the mV level. Secondly,we discussed the common-mode tolerance,differential mode tolerance and the voltage margin of the electric current which guaranteed the proper functioning of the measuring system. Based on the issues,we proposed a measuring system of compound action potential which was realized by the operational amplifier using 3-cascade methods. The system consisted of 3-cascade,automatic zero tracking and reference voltage. In this system,the amplification of the weak signal was realized and the background noise was eliminated effectively. Contemporarily,the system provided the efficient overvoltage protection. Results The compound action potential of the frog sciatic nerve which was only 11 mV and the electrically evoked compound action potential of guinea pig which was 17 μV were measured by this system. The experimental results showed that the accurate compound action potential could be obtained by this measuring system. Conclusions The 3-cascade structure and automatic zero tracking might be an effective way for the effective amplification and precise measurement of small signals. This system supplies a stably measuring method for the further research on the special property when the electrical signal stimulates the nerve fiber directly.