Non-rapid eye movement sleep

About: Non-rapid eye movement sleep is a research topic. Over the lifetime, 8661 publications have been published within this topic receiving 389465 citations. The topic is also known as: NREM.

Time course of sleep inertia after nighttime and daytime sleep episodes

Abstract: Sleep inertia refers to the period of reduced vigilance following upon awakening from sleep To investigate the time course of sleep inertia, self-ratings of alertness and reaction time in a memory task were repeatedly assessed after nighttime and daytime sleep episodes in healthy young men Alertness gradually increased and reaction time gradually decreased within the first hour after awakening Their time course could be described by exponential functions with time constants of 045 h and 03 h, respectively The data demonstrate that sleep inertia is a robust, quantifiable process that can be incorporated in models of sleep and vigilance

Stage 4 sleep in schizophrenia.

Abstract: THE stage 4 EEG (employing the Dement and Kleitman 1 nomenclature) of sleep, as measured in our laboratory, consists of high-voltage (over 50V) slow (under 4 cycles per second) activity occurring with a stipulated density (over 16 waves per 20second epoch, or over 50% of the epoch occupied by such slow waves). Stage 3 EEG represents a lesser density (10 to 16 waves per 20-second epoch) of this slow-wave activity. Stage 3 and 4 EEG constitute, along with spindles and K-complexes, the distinguishing features of nonrapid eye-movement (NREM) or slow-wave sleep. Both stage 3 and 4 EEG are maximal during the first few hours of sleep 1 and their distributions across the night may usefully be described as a function of the successive sleep cycles. 2 Stage 4 EEG reaches its highest level in early childhood 3 and then shows a hyper

Sleep fragmentation in normals: a model for sleepiness associated with upper airway resistance syndrome.

Abstract: Summary: Eight young adults underwent I night of auditory sleep fragmentation followed by four naps of the multiple sleep latency test and performance testing the next day. A latin-square design was used to compare results with baseline. Efforts were made to eliminate effects of learning on repeated performance tests. A mean of 303 arousals, lasting a mean of II seconds, disrupted nocturnal sleep. This sleep fragmentation was induced to mimic as closely as possible the nocturnal sleep disruption seen in subjects with upper airway resistance syndrome. There was a significant disruption of nocturnal sleep architecture with a significant overall decrease in slow-wave sleep (SWS) and a significant but more moderate decrease in rapid eye movement (REM) sleep during the fragmented night. The most interesting finding related to analysis by thirds of the night, which indicated an important increase over time in arousal threshold during SWS followed by REM sleep. This threshold increase was associated with a parallel increase in dB(A) levels needed to induce an arousal. Stages I and 2 nonrapid eye movement (NREM) sleep were less affected by the stimulation, but the amount of stage I NREM sleep decreased from the beginning to the end of the night, again indicating an increase in pressure to sleep. Following I night of sleep fragmentation, subjects had significantly shorter sleep latencies on the multiple sleep latency test for naps 2, 3 and 4. There was a significant relationship between percent nocturnal SWS and mean sleep latencies. The selected performance tests were not affected by I night of sleep fragmentation, despite the obvious sleepiness. Key Words: Sleep fragmentation­ Upper airway resistance syndrome-Sleepiness-Performance testing.