Donders Center for Cognition, Radboud University Nijmegen, Nijmegen, The Netherlands.
Clin Neurophysiol. 2011 Apr;122(4):687-95. doi: 10.1016/j.clinph.2010.10.038. Epub 2010 Nov 18.
In order to unravel the mechanisms underlying the "sudden" onset of spontaneous absences in genetically prone subjects, we investigated the immediate precursors of spike-wave discharges (SWDs) produced in cortico-thalamo-cortical neuronal networks.
A time-frequency analysis of the cortical and thalamic ECoG of WAG/Rij rats was accomplished with a continuous wavelet decomposition of SWDs, 3 s prior to the onset of SWDs (pre-SWD), and in control periods devoid of SWDs.
The pre-SWD ECoG consisted of delta and theta components in 80-90% of all SWDs simultaneously in cortex and thalamus, the co-occurrence of delta and theta was rare (7%) during control periods. The occurrence of delta and theta events in pre-SWDs in the cortex preceded that in the thalamus. The frequency of theta component in cortex correlated positively with that in thalamus, this correlation was less strong for delta.
Precursors of SWDs comprise of delta and theta, their co-occurrence is typical for non-epileptic periods. Thalamic and cortical theta are strongly related. Rhythmic precursors appear earlier in cortex than in thalamus, and this is in line with the cortical origin of SWD.
Simultaneous presence of delta and theta events in EEG is a condition for the occurrence of SWDs.
为了解释基因易感性个体中自发性缺失“突然”发作的机制，我们研究了皮质-丘脑-皮质神经元网络中产生棘波-慢波放电（SWD）的即时前体。
用 SWD 的连续小波分解对 WAG/Rij 大鼠的皮质和丘脑 ECoG 进行时频分析，在 SWD 发作前 3s（预 SWD）和无 SWD 的对照期进行分析。
80%-90%的 SWD 同时在皮质和丘脑出现 delta 和 theta 成分，在对照期 delta 和 theta 同时出现的情况很少（7%）。预 SWD 中皮质 delta 和 theta 事件的发生先于丘脑。皮质中 theta 成分的频率与丘脑呈正相关，与 delta 的相关性较弱。
SWD 的前驱包括 delta 和 theta，它们的同时出现是癫痫发作期以外的典型特征。丘脑和皮质的 theta 密切相关。节律性前驱在皮质中比在丘脑更早出现，这与 SWD 的皮质起源一致。
EEG 中 delta 和 theta 事件的同时出现是 SWD 发生的条件。
