NREM sleep is characterized by two hallmarks, namely K-complexes (KCs) during sleep stage N2 and cortical slow oscillations (SOs) during sleep stage N3. While the underlying dynamics on the neuronal level is well known and can be easily measured, the resulting behavior on the macroscopic population level remains unclear. On the basis of an extended neural mass model of the cortex, we suggest a ...

During the last few decades, much knowledge has been gained about sleep being a heterogeneous condition with several distinct sleep stages that represent fundamentally different physiological states. The same applies for the wake state which also comprises distinct global functional states (called vigilance stages). However, various terms and concepts have been introduced describing different a...

BACKGROUND Studies addressing the influence of early sexual maturation on the excess of body weight and height of children and adolescents are scarce. The aim of the study was to analyze the association of sexual maturation with excess body weight and height in children and adolescents. METHODS This was a cross-sectional study performed in Florianópolis city, Brazil, in 2007, with 2339 school...

Sleep is a vital physiological process with important restorative functions. Parasomnias are characterized by undesirable physical or verbal behaviors, such as walking or talking during sleep and occur in association with sleep, specific stages of sleep or sleep-wake transitions. The category of parasomnias comprises some of the most exceptional behavior disorders because complex and apparently...

Excessive fragmentary myoclonus during sleep consists of high amounts of brief twitch-like movements occurring asynchronously and asymmetrically in different body areas and has been reported to occur in association with a number of sleep disorders. It was analyzed using a new technique of quantification, the fragmentary myoclonus index (FMI). The FMI exhibited high rates in all stages of sleep ...

Breathing patterns early and late in the night, at the same sleep stage, were compared in six healthy subjects and 15 adults with nocturnal asthma, to try to identify changes of overnight bronchoconstriction, and breathing patterns at different sleep stages, to see whether there were changes related to sleep stages that were indicative of bronchoconstriction. Despite an average 31% fall in FEV1...

This review demonstrates that stress is closely related to impaired sleep in cross-sectional studies. In particular, the anticipation of high demands or effort the next day seems important. Sleep recordings show that stress is associated with shortened sleep, fragmentation, and possibly a reduction in sleep stages 3 and 4. Shortened or disturbed sleep causes increases in levels of traditional s...

We analyze complexity of sleep-EEG-signals using methods based on Higuchi’s fractal dimension and of the signal and a new symbolic method applied to signal’s derivative. We demonstrate that these methods may be helpful in diagnosis of sleep disorders the fractal dimension method differentiate between sleep stages while the symbolic method may differentiate between healthy subject and insomniacs...

The purpose of this study was to examine the effects of a truss mattress upon sleep and bed climate. The truss mattress which has been designed to decrease the pressure and bed climate humidity was tested. Six healthy female volunteers with a mean age of 23.3 years, served as subjects. The experiment was carried out under two conditions: a truss mattress (T) and a futon (F) (Japanese bedding). ...

A whole body indirect calorimeter provides accurate measurement of energy expenditure over long periods of time, but it has limitations to assess its dynamic changes. The present study aimed to improve algorithms to compute O(2) consumption and CO(2) production by adopting a stochastic deconvolution method, which controls the relative weight of fidelity to the data and smoothness of the estimat...