Cote K A, de Lugt D R, Langley S D, Campbell K B
School of Psychology, University of Ottawa, Canada.
J Sleep Res. 1999 Dec;8(4):263-72. doi: 10.1046/j.1365-2869.1999.00164.x.
During NREM sleep a very large amplitude wave-form, known as the K-complex, may be elicited upon presentation of an external stimulus. The present study compared the scalp distribution of a prominent negative wave peaking at about 550 ms and a later positive wave peaking between 900 and 1300 ms in stage 2 and slow wave sleep (SWS). Nine subjects spent a single night in the laboratory. They were presented with an 80 dB SPL 2000 Hz auditory tone pip every 15 s. The EEG was recorded from 29 electrode sites and referenced to the nose. A K-complex was elicited on 34% of trials in stage 2 and on 46% of trials in SWS. A negative wave peaking at 330 ms was larger on trials in which the K-complex was elicited than on trials in which it was not. The large amplitude N550 was readily observable on trials in which the K-complex was elicited but could not be observed on trials in which it was not. The N550 was bilaterally symmetrical and was maximum over fronto-central areas of the scalp in both stage 2 and SWS. It inverted in polarity at the mastoid and inferior parietal regions. The scalp distribution of N550 significantly differed between stage 2 and SWS. It showed a sharper decline in amplitude over parietal and posterior-inferior areas of the scalp in stage 2 compared to SWS. A later P900 was maximum over centro-frontal areas of the scalp and was also bilaterally symmetrical. It showed a significantly sharper decline in amplitude over widespread inferior areas during SWS. Because the scalp maps of the N550 and P900 are different in stage 2 and SWS, their intracranial sources must also be different.
在非快速眼动睡眠期间，当受到外部刺激时，可能会引出一种非常大的波形，即K复合波。本研究比较了在第二阶段睡眠和慢波睡眠（SWS）中，一个在约550毫秒达到峰值的显著负波和一个在900至1300毫秒之间达到峰值的较晚正波的头皮分布情况。九名受试者在实验室度过了一个晚上。每隔15秒向他们呈现一次80分贝声压级、2000赫兹的听觉短音。脑电图从29个电极部位记录，并以鼻为参考电极。在第二阶段睡眠的34%的试验中以及慢波睡眠的46%的试验中引出了K复合波。在引出K复合波的试验中，一个在330毫秒达到峰值的负波比未引出K复合波的试验中的负波更大。在引出K复合波的试验中很容易观察到大幅的N550，但在未引出K复合波的试验中则观察不到。N550在双侧是对称的，在第二阶段睡眠和慢波睡眠中，在头皮的额中央区域达到最大值。它在乳突和顶叶下部区域极性反转。N550的头皮分布在第二阶段睡眠和慢波睡眠之间有显著差异。与慢波睡眠相比，它在第二阶段睡眠中在头皮的顶叶和后下部区域的振幅下降更为明显。较晚的P900在头皮的中央额叶区域达到最大值，并且也是双侧对称的。在慢波睡眠期间，它在广泛的下部区域的振幅下降明显更陡。由于N550和P900在第二阶段睡眠和慢波睡眠中的头皮图谱不同，它们的颅内来源也必然不同。
