The integration of segregated brain functional modules is a prerequisite for conscious awareness during wakeful rest. Here, we test the hypothesis that temporal integration, measured as longterm memory in the history of neural activity, is another important quality underlying conscious awareness. For this aim, we study the temporal memory of blood oxygen level-dependent signals across the human nonrapid eye movement sleep cycle. Results reveal that this property gradually decreases from wakefulness to deep nonrapid eye movement sleep and that such decreases affect areas identified with default mode and attention networks. Although blood oxygen level-dependent spontaneous fluctuations exhibit nontrivial spatial organization, even during deep sleep, they also display a decreased temporal complexity in specific brain regions. Conversely, this result suggests that long-range temporal dependence might be an attribute of the spontaneous conscious mentation performed during wakeful rest.T he human brain displays complex spatiotemporal patterns of energy-consuming activity, even in the absence of an explicit task or stimulation (1). Large efforts have been devoted to the study of spontaneous neural activity encoded in the slow (∼0.1 Hz) fluctuations of the blood oxygen level-dependent (BOLD) signal, which are measured with functional MRI (fMRI). Nontrivial spatial organization of functional brain activity in resting state networks (RSNs) was consistently shown (2-4), comprising brain regions with high BOLD signal coherence and anatomical consistency with systems activated during task performance or stimulation (5).Remarkably, although human nonrapid eye movement (NREM) sleep is characterized by impaired awareness and reduced conscious mentation, organization into RSNs is preserved in light sleep (6) and to a large extent, deeper sleep stages (7, 8) (SI Appendix, Fig. S8.1). In particular, the default mode network (DMN; a set of task-deactivated regions implied with internal conscious cognitive processes) (9, 10) was repeatedly observed during deep sleep, albeit with reduced frontal connectivity (11,12). Although brain modules are preserved, even in the absence of conscious awareness, their functional integration is greatly impaired (8,13,14), which was predicted by an information integration account of consciousness (15). These results suggest that ongoing conscious mentation is not the only origin of RSN activity, whereas the level of consciousness is reflected in the interaction of functional networks.However, brain activity is not completely characterized in the spatial domain only. fMRI BOLD signals display rich temporal organization, including scale-free 1/f power spectra and long-range temporal autocorrelations (16)(17)(18), with activity at any given time being influenced by the previous history of the system up to several minutes into the past. These landmarks of complex information processing and rapid adaptability are shared by many systems found in nature (19,20). Evidence for such properties is also manifest...

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Acute treatment of SE, and particularly SRSE and ventilation, are associated with high hospital costs and prolonged LOS. Extrapolation to the whole of Germany indicates that SE causes hospital costs of >€200 million per year. Along with the demographic change, incidence of SE will increase and costs for hospital treatment and sequelae of SE will rise.