Rapid eye movement sleep

About: Rapid eye movement sleep is a research topic. Over the lifetime, 3740 publications have been published within this topic receiving 183415 citations. The topic is also known as: REM sleep & REMS.

Muscle tone suppression and stepping produced by stimulation of midbrain and rostral pontine reticular formation

Abstract: Stimulation of the midbrain retrorubral (RRN), ventral paralemniscal tegmental field (vFTP), reticular tegmental (TRN), and pedunculopontine tegmental (PPN) nuclei was found to produce bilateral suppression of muscle tone in the unanesthetized, decerebrate animal. The RRN is the most rostral area shown to produce such suppression. This muscle tone suppression was frequency- and intensity-dependent. At low stimulus intensities, bilateral suppression was produced at these sites. At higher current and frequency levels, 2 types of muscle responses were found, excitation in PPN and RRN and initial suppression followed by excitation in TRN and vFTP. The mean latency to muscle tone suppression was not significantly different in TRN (36.8 msec) and RRN (36.5 msec). However, muscle tone suppression latency was significantly shorter in vFTP (31 msec) and PPN (27.1 msec). In addition to muscle tone suppression, stepping-like activity could be elicited at the same points by consecutive train stimulations in PPN and single train stimulation in TRN and vFTP. Thus, systems producing atonia are colocalized with those producing locomotion. We hypothesize that the midbrain atonia regions control more caudal regions producing muscle tone suppression in REM sleep, and that the locomotor and atonia eliciting regions are normally coactivated during REM sleep.

Sleep-promoting and hypothermic effects of daytime melatonin administration in humans.

Abstract: Sleep-promoting and hypothermic effects of orally administered melatonin during the daytime were assessed using a placebo-controlled, double-blind, cross-over design. Following a 7-hour nighttime sleep opportunity, healthy young male subjects (n = 8) were given either a placebo or one of three doses of melatonin (1 mg, 10 mg, and 40 mg) at 1000 hours. Sleep was polygraphically assessed in a 4-hour sleep opportunity from 1200 to 1600 hours. All doses of melatonin significantly shortened the latency to sleep onset. Melatonin also significantly increased total sleep time and decreased wake after sleep onset (WASO). Sleep following melatonin administration contained significantly more stage 2 and less stage 3-4, while stage 1 and rapid eye movement (REM) sleep were unaffected. In addition to the sleep-promoting effects, melatonin completely suppressed the normal diurnal rise of core body temperature. These data suggest that melatonin may be an effective method of promoting sleep for individuals attempting to sleep during their subjective day, such as shiftworkers and individuals rapidly traveling across multiple time zones.

Essential Thalamic Contribution to Slow Waves of Natural Sleep

Abstract: Slow waves represent one of the prominent EEG signatures of non-rapid eye movement (non-REM) sleep and are thought to play an important role in the cellular and network plasticity that occurs during this behavioral state. These slow waves of natural sleep are currently considered to be exclusively generated by intrinsic and synaptic mechanisms within neocortical territories, although a role for the thalamus in this key physiological rhythm has been suggested but never demonstrated. Combining neuronal ensemble recordings, microdialysis, and optogenetics, here we show that the block of the thalamic output to the neocortex markedly (up to 50%) decreases the frequency of slow waves recorded during non-REM sleep in freely moving, naturally sleeping-waking rats. A smaller volume of thalamic inactivation than during sleep is required for observing similar effects on EEG slow waves recorded during anesthesia, a condition in which both bursts and single action potentials of thalamocortical neurons are almost exclusively dependent on T-type calcium channels. Thalamic inactivation more strongly reduces spindles than slow waves during both anesthesia and natural sleep. Moreover, selective excitation of thalamocortical neurons strongly entrains EEG slow waves in a narrow frequency band (0.75–1.5 Hz) only when thalamic T-type calcium channels are functionally active. These results demonstrate that the thalamus finely tunes the frequency of slow waves during non-REM sleep and anesthesia, and thus provide the first conclusive evidence that a dynamic interplay of the neocortical and thalamic oscillators of slow waves is required for the full expression of this key physiological EEG rhythm.

Human alpha oscillations in wakefulness, drowsiness period, and REM sleep: different electroencephalographic phenomena within the alpha band

Abstract: Cortical oscillations in the range of alpha activity (8-13 Hz) are one of the fundamental electrophysiological phenomena of the human electroencephalogram (EEG). Evidence from quantitative EEG data has shown that their electrophysiological features, cortical generation mechanisms, and therefore, their functional correlates vary along the sleep-wake continuum. Specifically, spectral microstructure and EEG coherence levels between anterior and posterior cortical regions permit to differentiate among alpha activity spontaneously appearing in relaxed wakefulness with eyes closed, drowsiness period, and REM sleep, by reflecting distinct properties of neural networks involved in its cortical generation as well as a different interplay between cortical generators, respectively. Besides, the dissimilar spatiotemporal features of brain electrical microstates within the alpha range reveals a different geometry of active neural structures underlying each alpha variant or, simply, changes in the stability level of neural networks during each brain state. Studies reviewed in this paper support the hypothesis that two different alpha variants occur during human REM sleep: 'background responsive alpha activity', blocked over occipital regions when rapid eye movements are present, and 'REM-alpha bursts', non modulated by the alteration of tonic and phasic periods. Altogether, evidence suggests that electrophysiological features of human cortical oscillations in the alpha frequency range vary across different behavioural states, as well as within state, reflecting different cerebral phenomena with probably dissimilar functional meaning.