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Consciousness and Anesthesia

M. T. Alkire, A. G. Hudetz, G. Tononi
2008 Science  
Consciousness vanishes when anesthetics produce functional disconnection in this posterior complex, interrupting cortical communication and causing a loss of integration; or when they lead to bistable,  ...  Although anesthesia undoubtedly induces unresponsiveness and amnesia, the extent to which it causes unconsciousness is harder to establish.  ...  (C) Sleeping reduces cortical integration in humans.  ... 
doi:10.1126/science.1149213 pmid:18988836 pmcid:PMC2743249 fatcat:5s4uhdywrvdstitecnoo5bmnm4

Temporal dynamics of cortical sources underlying spontaneous and peripherally evoked slow waves [chapter]

Brady A. Riedner, Bradley K. Hulse, Michael J. Murphy, Fabio Ferrarelli, Giulio Tononi
2011 Progress in Brain Research  
Slow waves are the most prominent electroencephalographic (EEG) feature of non-rapid eye movement (NREM) sleep.  ...  The currents produced by the near-synchronous slow oscillation of large populations of neurons appear on the scalp as EEG slow waves (Amzica and Steriade, 1997).  ...  ), and funding provided by Philips-Respironics, Inc.  ... 
doi:10.1016/b978-0-444-53839-0.00013-2 pmid:21854964 pmcid:PMC3160723 fatcat:xh3zn7ibrbhgdokokdphzu6vwi

Targeting Arousal and Sleep through Noninvasive Brain Stimulation to Improve Mental Health

Tim Geiser, Elisabeth Hertenstein, Kristoffer Fehér, Jonathan G. Maier, Carlotta L. Schneider, Marc A. Züst, Marina Wunderlin, Christian Mikutta, Stefan Klöppel, Christoph Nissen
2020 Neuropsychobiology  
slow waves, sleep spindles, cross-frequency coupling of brain oscillations, local sleep-wake regulation, and REM sleep and (2) targeting these with specific NIBS techniques.  ...  This work summarizes current concepts of the regulation of arousal and sleep and its modulation through noninvasive brain stimulation (NIBS), including transcranial magnetic, current, and auditory stimulation  ...  Of further interest is that inducing sleep slow waves, e.g., through acoustic stimulation, in patients with mild cognitive impairment and slow-wave deficits might improve memory and even decelerate the  ... 
doi:10.1159/000507372 pmid:32408296 fatcat:uqwzdfe5ezcudbmhodjtuhuwua

Neurophysiological support of consciousness during waking and sleep

C Gottesmann
1999 Progress in Neurobiology  
During slow wave sleep, all these brain stem in¯uences sustaining the cortical state decrease and transiently disappear just prior to onset of REM sleep.  ...  Therefore, it is understandable that, during waking, mental activity is re¯ective and rational, and that psychological content is less intense during slow wave sleep.  ...  Rossi et al. (1965) showed that the cortical recovery cycle of the visual cortex tested by radiation stimulation is shorter during slow wave sleep than during waking and still slightly shorter during  ... 
doi:10.1016/s0301-0082(99)00014-3 pmid:10515665 fatcat:onq74dgk6zaprlqhp6ajrmnwf4

Brainstem regulation of slow-wave-sleep

Christelle Anaclet, Patrick M Fuller
2017 Current Opinion in Neurobiology  
It was specifically shown that GABAergic neurons located in the medullary brainstem parafacial zone (PZ GABA ) are not only necessary for normal slow-wave-sleep (SWS) but that their selective activation  ...  is sufficient to induce SWS in behaving animals.  ...  of slow waves and delta waves that are characteristic of cortical synchronization and SWS and behavioral sleep.  ... 
doi:10.1016/j.conb.2017.04.004 pmid:28500870 pmcid:PMC5607774 fatcat:3fqfg3k6aveyhi76xryg3htpfy

Human Sleep Neurophysiology

2006 Journal of Sleep Research  
The human sleep EEG is characterised by the occurrence of distinct oscillatory events such as delta waves, sleep spindles, and alpha activity.  ...  The periodicity in the occurrence of oscillatory events was not affected by sleep deprivation.  ...  We also examined whether sleep-deprivation induced changes in A1AR binding and the EEG are attenuated by 300 mg slow-release caffeine.  ... 
doi:10.1111/j.1365-2869.2006.00540_23.x fatcat:bmgtp6kovvcmzgouetz2ebhs2e

Brain Function in Physiologically, Pharmacologically, and Pathologically Altered States of Consciousness

Pierre Boveroux, Vincent Bonhomme, Mélanie Boly, Audrey Vanhaudenhuyse, Pierre Maquet, Steven Laureys
2008 International Anesthesiology Clinics  
During deep sleep (slow wave stage III to IV), cerebral deactivations have been shown in a wide fronto-parietal network encompassing the polymodal associative cortices: bilateral lateral frontal regions  ...  precuneal and posterior cingulate cortices during wakefulness and sleep: stage II (st II), slow wave (st III-IV), and rapid eye movement sleep (REM) (mean values and 95% confidence interval).  ... 
doi:10.1097/aia.0b013e318181a8b3 pmid:18617821 fatcat:4ktb23mjh5f5dii7b4pezmi7re

The dreaming sleep stage: A new neurobiological model of schizophrenia?

C. Gottesmann
2006 Neuroscience  
Moreover, in both states, there is dorsolateral prefrontal deactivation as shown by the decrease of blood flow.  ...  Consequently, rapid eye movement sleep could become a useful new neurobiological model of this mental disease since more functional than current rat models using stimulation, lesion or drugs.  ...  This cortical deactivation also cooperates to induce the glutamate deficit in nucleus accumbens (Grace, 2000) .  ... 
doi:10.1016/j.neuroscience.2006.02.082 pmid:16650940 fatcat:tmyxbgflcfcrzhsxq2zbdjdjqy

Functional neuroimaging of normal human sleep by positron emission tomography

2000 Journal of Sleep Research  
The personal research reported in this review was supported by FNRS grants, by Special Funds for Scienti®c Research of the University of LieÁ ge and by the Queen Elisabeth Medical Foundation.  ...  The author would like to thank Allan Braun, Jesper Andersson and Naofumi Kajimura for their sleep PET images.  ...  Early observations in chimpanzees reported slow waves and K complexes in the hippocampus during non-REM sleep but in the human hippocampal complex, stage 4 sleep was essentially characterized by low voltage  ... 
doi:10.1046/j.1365-2869.2000.00214.x pmid:11012860 fatcat:f3zhpf4g7ncjrfxqdidwu5nr2a

Enhancement of sleep slow waves: underlying mechanisms and practical consequences

Michele Bellesi, Brady A. Riedner, Gary N. Garcia-Molina, Chiara Cirelli, Giulio Tononi
2014 Frontiers in Systems Neuroscience  
Here we first review the evidence that it is possible to enhance sleep slow waves in humans using transcranial direct-current stimulation (tDCS) and transcranial magnetic stimulation.  ...  Finally, we discuss automated algorithms that read the EEG and, in real-time, adjust the stimulation parameters in a closed-loop manner to obtain an increase in sleep slow waves and avoid undesirable arousals  ...  ACKNOWLEDGMENTS This work was supported by a grant from Philips Healthcare.  ... 
doi:10.3389/fnsys.2014.00208 pmid:25389394 pmcid:PMC4211398 fatcat:bprt7mlobzbnbngpyiyvvcqe6q

Sleep and Consciousness [chapter]

Yuval Nir, Marcello Massimini, Melanie Boly, Giulio Tononi
2013 Neuroimaging of Consciousness  
At the same time as changes in consciousness occur, brain activity undergoes major changes through an orderly progression of sleep stages, which can be identi fi ed by recording the electroencephalogram  ...  Sleep offers a unique opportunity to relate changes in brain activity to changes in consciousness.  ...  What are the spatial relationships between spontaneous slow waves and covert bistability, as revealed by slow waves evoked by cortical stimulation?  ... 
doi:10.1007/978-3-642-37580-4_9 fatcat:oozz3wssufad3iyrm64f5ngaxe

Functional imaging of sleep

2003 Swiss Archives of Neurology and Psychiatry  
We found occipital activation and frontal deactivation during REM sleep.  ...  Sleep has traditionally been monitored by electrophysiological means such as electroencephalography.  ...  [27] reported, with fMRI, a robust signal decrease during visual stimulation (a stroboscopic flash unit functioning at 8 Hz) in the rostromedial occipital cortex in slow-wave sleep.  ... 
doi:10.4414/sanp.2003.01410 fatcat:4jtfae2sq5gndj6v7fefx5fv4y

Grouping of brain rhythms in corticothalamic systems

M. Steriade
2006 Neuroscience  
The role of slow-wave sleep oscillation in consolidating memory traces acquired during wakefulness is being explored in both experimental animals and human subjects.  ...  they also occur during slow-wave sleep.  ...  This article is dedicated to Claude, with the hope that, when examining electrical activities of the cerebrum in humans, she will consider useful the concept of unified brain oscillations.  ... 
doi:10.1016/j.neuroscience.2005.10.029 pmid:16343791 fatcat:ntruqqbeffczbjkjqni4b2chxi

Cortical Deactivation Induced by Subcortical Network Dysfunction in Limbic Seizures

D. J. Englot, B. Modi, A. M. Mishra, M. DeSalvo, F. Hyder, H. Blumenfeld
2009 Journal of Neuroscience  
We recently developed an animal model that, like human limbic seizures, exhibits neocortical deactivation including cortical slow waves and reduced cortical cerebral blood flow (CBF).  ...  Cortical slow oscillations and behavioral arrest could be reconstituted in fornix-lesioned animals by inducing synchronous activity in the hippocampus and septal area, implying involvement of a downstream  ...  in cortical slow waves and behavioral arrest.  ... 
doi:10.1523/jneurosci.3846-09.2009 pmid:19828814 pmcid:PMC2778759 fatcat:ye5hnbfrqfg7fihfzz2krgp6xy

Functional Neuroimaging Insights into the Physiology of Human Sleep

Thien Thanh Dang-Vu, Manuel Schabus, Martin Desseilles, Virginie Sterpenich, Maxime Bonjean, Pierre Maquet
2010 Sleep  
In particular, they have demonstrated that NREM sleep oscillations (spindles and slow waves) are indeed associated with increases in brain activity in specific subcortical and cortical areas involved in  ...  On the one hand, REM sleep has been associated with the activation of the pons, thalamus, limbic areas, and temporo-occipital cortices, and the deactivation of prefrontal areas, in line with theories of  ...  visual (and not auditory) sensory cortices. 105 In a follow-up study, the same authors further demonstrated that the stimulus-induced negative BOLD effects, again primarily found in stage 2 NREM sleep  ... 
doi:10.1093/sleep/33.12.1589 pmid:21120121 pmcid:PMC2982729 fatcat:vent4sw3inclnilkntxqrp53ia
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