Sleep in a 1-year diary from the mid-18th century.

A 1-year systematic diary was kept by an anonymous diarist in Hamburg in the year 1755-1756. Sleep, activities, food intake, urine volume, and meteorological data were documented daily. The systematic recording of sleep and naps, with an accuracy of a quarter of an hour allowed analysis of the placement, duration, and consistency of sleep.

The history of sleep research and sleep medicine in Europe.

Sleep became a subject of scientific research in the second half of the 19th century. Since sleep, unlike other physiological functions, cannot be attributed to a specific organ, there was no distinct method available to study sleep until then. With the development of physiology and psychology, and a rapidly increasing knowledge of the structure and functioning of the nervous system, certain aspects of sleep became accessible to objective study.

Asynchronous Antarctic and Greenland ice-volume contributions to the last interglacial sea-level highstand.

The last interglacial (LIG; ~130 to ~118 thousand years ago, ka) was the last time global sea level rose well above the present level. Greenland Ice Sheet (GrIS) contributions were insufficient to explain the highstand, so that substantial Antarctic Ice Sheet (AIS) reduction is implied. However, the nature and drivers of GrIS and AIS reductions remain enigmatic, even though they may be critical for understanding future sea-level rise.

Black Sea outflow response to Holocene meltwater events.

During the Holocene, North American ice sheet collapse and rapid sea-level rise reconnected the Black Sea with the global ocean. Rapid meltwater releases into the North Atlantic and associated climate change arguably slowed the pace of Neolithisation across southeastern Europe, originally hypothesized as a catastrophic flooding that fueled culturally-widespread deluge myths. However, we currently lack an independent record linking the timing of meltwater events, sea-level rise and environmental change with the timing of Neolithisation in southeastern Europe.

End-member modelling as a tool for climate reconstruction-An Eastern Mediterranean case study.

The Eastern Mediterranean Sea is a sink for terrigenous sediments from North Africa, Europe and Asia Minor. Its sediments therefore provide valuable information on the climate dynamics in the source areas and the associated transport processes. We present a high-resolution dataset of sediment core M40/4_SL71, which was collected SW of Crete and spans the last ca.

The Development of Sleep Medicine: A Historical Sketch.

For centuries the scope of sleep disorders in medical writings was limited to those disturbances which were either perceived by the sleeper him- or herself as troublesome, such as insomnia, or which were recognized by an observer as strange behavioral acts during sleep, such as sleepwalking or sleep terrors. Awareness of other sleep disorders, which are caused by malfunction of a physiological system during sleep, such as sleep-related respiratory disorders, were widely unknown or ignored before sleep monitoring techniques became available, mainly in the second half of the 20(th) century. Finally, circadian sleep-wake disorders were recognized as a group of disturbances by its own only when chronobiology and sleep research began to interact extensively in the last two decades of the 20(th) century.

Guidelines for the recording and evaluation of pharmaco-sleep studies in man: the International Pharmaco-EEG Society (IPEG).

The International Pharmaco-EEG Society (IPEG) presents guidelines summarising the requirements for the recording and computerised evaluation of pharmaco-sleep data in man. Over the past years, technical and data-processing methods have advanced steadily, thus enhancing data quality and expanding the palette of sleep assessment tools that can be used to investigate the activity of drugs on the central nervous system (CNS), determine the time course of effects and pharmacodynamic properties of novel therapeutics, hence enabling the study of the pharmacokinetic/pharmacodynamic relationship, and evaluate the CNS penetration or toxicity of compounds. However, despite the presence of robust guidelines on the scoring of polysomnography -recordings, a review of the literature reveals inconsistent -aspects in the operating procedures from one study to another.

Forerunners of REM sleep.

The development of sleep research can be divided into two main periods. The first one was initiated in 1863 by the first systematic measurement of the depth of sleep, the second in 1953 by the discovery of recurrent episodes of rapid eye movements in sleep. The main methodological procedure in the first of these two periods was the measurement of a single physiological variable, while beginning with long-term measurements of the electroencephalogram (EEG) in sleep, multi-channel, polygraphic recording became the method of choice for sleep studies.

How treatment affects cognitive deficits in patients with sleep disorders: methodological issues and results.

Sleep disorders are frequently associated with impaired performance although the type and extent of cognitive deficits varies widely between different types of sleep disorders. Treatment is expected to ameliorate these deficits. However, cognitive functioning and its change with treatment depend on numerous factors.

Modeling napping, post-lunch dip, and other variations in human sleep propensity.

Study Objectives: To model sleep propensity (SP) as a continuous variable across 24 hours and to model the post-noon nap zone, or post-lunch dip in performance, and the early evening trough in SP.

Methods: The present model is a variant of the 2-process model with 2 major modifications. (1) The circadian threshold process was replaced by sleep drive R, derived from REM sleep propensity, which shows a strong circadian modulation.

Rethinking sleep analysis.

Visual sleep scoring is the obligatory reference for sleep analysis. An essential step in sleep scoring is sleep staging. This technique was first described in 1937 and later adapted 3 times: first, in 1957, after the detection of rapid eye movement (REM) sleep, when electrooculography (EOG) was added; second, in 1968, when sleep staging was standardized and electromyography (EMG) was added; and third, in 2007, to integrate accumulated knowledge from sleep science, adding arousals and respiratory, cardiac, and movement events.

When sleep is perceived as wakefulness: an experimental study on state perception during physiological sleep.

While electrophysiologically measured sleep and perception of sleep generally concur, various studies have shown this is not always the case. The objective of the present study was to assess the perception of actual state during sleep by the technique of planned awakenings and interviewing subjects on the preawakening state. Sixty-eight (43 females, 25 males) young (mean age: 24.

A taxonomic analysis of sleep stages.

Study Objectives: To study the structure of human sleep at the level of sleep stages. We applied taxonomic statistics to detect significant configurations (types) of different physiologic variables and their relationship to sleep stages. DESIGN AND STATISTICS: Polygraphic sleep recordings from 32 subjects (normal sleepers as well as patients with insomnia, sleep apnea, or narcolepsy; n = 8 per group) were visually scored and submitted to a configural frequency analysis.

Awakening from sleep.

Awakening is a crucial event for the organism. The transition from sleep to waking implies physiological processes which lead to a new behavioural state. Spontaneous awakenings have varying features which may change as a function of several factors.