Inoue M, Van Luijtelaar E L, Vossen J M, Coenen A M
Department of Psychology, University of Nijmegen, The Netherlands.
Electroencephalogr Clin Neurophysiol. 1992 Mar-Apr;84(2):172-9. doi: 10.1016/0168-5597(92)90022-4.
Flash evoked visual potentials (VEPs) were recorded in freely moving WAG/Rij rats. These rats show spontaneously occurring spike-wave discharges in the EEG, interpreted as absence-like seizures. VEPs recorded during the presence of spike-wave discharges were compared with those obtained during normal states of vigilance as quiet wakefulness, slow-wave sleep and REM sleep. Almost similar VEPs were recorded during wakefulness and REM sleep, whereas during slow-wave sleep the second positive peak (P2) was considerably larger. In comparison with normal sleep-wake states, VEPs during spike-wave discharges showed unique changes, such as a decrease in the N1 amplitude, an increase of the P4 amplitude and an enhanced afterdischarge. Other characteristics were similar to those seen during slow-wave sleep, such as an increase of the P2 amplitude and a diminished P2-N3-P3 complex. These findings indicate sensory alterations during a spike-wave discharge. As expressed in the decrease of N1, afferent information cannot enter the thalamus during the rhythmic oscillatory mode. Such alterations may underlie the lowered responsiveness to external stimuli during spike-wave activity.
在自由活动的WAG/Rij大鼠中记录闪光诱发视觉诱发电位（VEP）。这些大鼠脑电图显示自发出现棘波放电，被解释为类失神发作。将棘波放电期间记录的VEP与在安静觉醒、慢波睡眠和快速眼动睡眠等正常警觉状态下获得的VEP进行比较。在觉醒和快速眼动睡眠期间记录到的VEP几乎相似，而在慢波睡眠期间第二个正峰（P2）明显更大。与正常睡眠-觉醒状态相比，棘波放电期间的VEP表现出独特变化，如N1波幅降低、P4波幅增加和后放电增强。其他特征与慢波睡眠期间所见相似，如P2波幅增加和P2-N3-P3复合波减弱。这些发现表明棘波放电期间存在感觉改变。如N1降低所示，在节律性振荡模式下传入信息无法进入丘脑。这种改变可能是棘波活动期间对外界刺激反应性降低的基础。
