Human deep sleep is characterized by reduced sensory activity, responsiveness to stimuli, and conscious awareness. Given its ubiquity and reversible nature, it represents an attractive paradigm to study the neural changes which accompany the loss of consciousness in humans. In particular, the deepest stages of sleep can serve as an empirical test for the predictions of theoretical models relati...

STUDY OBJECTIVES The program provides a unique opportunity to compare a large number of scorers with varied levels of experience to determine sleep stage scoring agreement. The objective is to examine areas of disagreement to inform future revisions of the AASM Manual for the Scoring of Sleep and Associated Events. METHODS The sample included 9 record fragments, 1,800 epochs and more than 3,2...

The goal of this study is to contribute to discussions about age-related changes in electroencephalogram (EEG) complexity. Eight characteristics of complexity were evaluated for sleep EEG of 175 healthy subjects. The complexity of the sleep EEG significantly increased up to the age of about 60 years. Over 60 years, the complexity stagnated or slightly decreased. The same tendencies were manifes...

The sleeping neocortex shows nested oscillatory activity in different frequency ranges, characterized by fluctuations between "up-states" and "down-states." High-density neuronal ensemble recordings in rats now reveal the interaction between synchronized activity in the hippocampus and neocortex: Electroencephalographic sharp waves in the hippocampus were more probable during down-states than d...

OBJECTIVE Evaluate the efficacy of ramelteon, an MT/1MT2-receptor agonist, for the treatment of transient insomnia in healthy adults. DESIGN Randomized, double-blind, placebo-controlled design using a model of transient insomnia related to sleeping in a novel environment. SETTING Fourteen sleep research centers. PARTICIPANTS Healthy adults (N=375; 228 women), aged 35 to 60 years, who had ...

In this paper we report a detection method for different sleep stages and it is based on a single-channel electroencephalogram (EEG) system. The system is simple and can be easily setup in homes to perform sleep EEG recording, overnight sleep EEG automatic staging, and sleep quality evaluation. EEG data of 14 sleeping subjects were recorded through the entire night. All subjects were within the...

BACKGROUND Changes caused by clonidine in rodent electroencephalograms (EEG) have been reported with some inconsistency. For this reason, a pre-clinical study was conducted in order to confirm previous findings with both a standard spectral analysis and a sleep stage scoring procedure. In addition, a nonlinear technique for analysing the time-varying signals was implemented to compare its perfo...

While the functions of sleep remain largely unknown, one of the most exciting and contentious hypotheses is that sleep contributes importantly to memory. A large number of studies offer a substantive body of evidence supporting this role of sleep in what is becoming known as sleep-dependent memory processing. This review will provide evidence of sleep-dependent memory consolidation and sleep-de...

Digital acquisition and analysis of sleep data has become more common over the past 20 years. Many investigators have developed strategies to record and analyze sleep in a quantitative way. Initially, digital recording and analysis were restricted by technical limitations. With current technology, the technical limitations of computer acquisition, data storage, and analysis are less constrainin...