似昼夜节律与学习效应对脑事件相关电位P_(300)的影响

Both circadian rhythm and repeated-testing act on event related potential P_(300)

目的 探讨似昼夜节律和学习效应对脑事件相关电位 P30 0 成分的影响 .方法 8名被试者在非连续的 5 d的实验中每天在 5个时间点 (7:0 0 ,12 :0 0 ,16 :0 0 ,2 0 :0 0和 0 :0 0 )重复相同的听觉 Oddball模式测试以诱发脑事件相关电位(ERP) .然后测量各次的 ERP P30 0 成分 ,得到其潜伏期及波幅 .结果 P30 0 波幅和潜伏期随着一天中时间变化而变化 .上午的 P30 0 波幅明显高于下午的波幅 .重复测量也使 P30 0波幅从第 1个实验日的平均 13.0μV降至第 5个实验日的 9.2μV.P30 0 潜伏期随着重复测试的增加出现了习服 ,它从第 2个实验日的平均 35 0 .6 ms缩短为第 5个实验日的平均 343.5ms.结论 似昼夜节律和学习效应对脑事件相关电位 P30 0 成分的波幅和潜伏期均有影响 .

AIM To investigate the effects of circadian rhythm and repeated testing on event related potential (ERP) P 300 component. METHODS Every subject (n=8) was tes-ted with a standard aural oddball paradigm to obtain ERP P 300. They were tested at 5 timepoints (7:00, 12:00, 16:00, 20:00, 0:00) per day in 5 days with an interval of at least 1 wk between 2 test days. In each test ERP was recorded. RESULTS Amplitude and latency of P 300 changed with the timeof the day. The amplitude of P 300 was significantly higher in the morning than in the afternoon. It also habituated across test days from a mean of 13.0 μV on the 1st day to a mean of 9.2 μV on the 5th day. Latency of P 300 also habituated across test days; it decreased from a mean of 350.6 ms on the 2nd day to a mean of 343.5 ms on the 5th day. CONCLUSION Both circadian rhythm and repeated testing can influence amplitude and latency of ERP P 300.