The dimensionality of human's electroencephalogram during sleep.

In order to perform an analysis of nonlinear EEG-dynamics we investigated the EEG of ten male probands during sleep. According to Rechtschaffen and Kales (1968) we scored the sleep-EEG and applied an algorithm, proposed by Grassberger and Proccaccia (1983) to compute the correlation dimension of different sleep stages. The correlation dimension characterizes the dynamics of the EEG signal and estimates the degrees of freedom of the signal under study. We could demonstrate, that the EEG of slow wave sleep stages depicts a dimensionality, which is two units smaller than that of light or REM sleep.

Functional properties of the brain during sleep under subchronic zopiclone administration in man.

Zopiclone, a non-benzodiazepine, has been shown to be efficient in the treatment of transient, short-term or chronic sleep disorders. Apart from its hypnotic effects zopiclone has anxiolytic, anticonvulsant and myorelaxant properties and is therefore hardly distinguishable from benzodiazepines. Dependence liability and discontinuation effects have been reported to be less pronounced. Therefore zopiclone seems to be a hypnotic drug which may cause fewer side effects than conventional benzodiazepines. From the electrophysiological point of view one requires from a hypnotic drug the induction of a physiological sleep pattern as well as no alterations of information processing by the brain. The…

The association between psychopathological aspects and CT measurements in affective disorders.

Imbalance between the neuromodulatory actions of corticotropin-releasing hormone and corticosterone as a pathophysiologic mechanism in panic disorder

Effects of corticotropin-releasing hormone on respiratory parameters during sleep in normal men.

Corticotropin-releasing hormone (CRH) is well-known to be a centrally acting respiratory stimulant after systemic application both in healthy subjects and in patients suffering from respiratory failure. In order to study the effects of CRH on sleep EEG and respiratory parameters during sleep, 14 healthy male volunteers were investigated in a single-blind placebo controlled design. After an adaptation night, polysomnography was performed during two successive nights between 23.00 hrs. and 7.00 hrs. During one night placebo was applied, on the other 50 μg ovine CRH was administered intravenously as a bolus every hour from 0.00 hrs. to 6.00 hrs. For the assessment of respiration, blood oxygen …

Development of a rating scale for quantitative measurement of the alcohol withdrawal syndrome

The alcohol withdrawal syndrome consists of autonomic, neurological and mental symptoms. For its assessment, these symptoms have to be rated in a quantitative and valid manner. We developed a new rating scale for mild and moderate alcohol withdrawal states. Difficulty, discrimination coefficient, internal consistency, and the principal component analysis were assessed. External validation was tested on a separate sample of inpatients. Eight of 12 original items fulfilled test-the-oretical criteria. From these a psychosensory and an autonomic factor have been extracted. This instrument can be used repeatedly for clinical assessment as well as for evaluation of the alcohol withdrawal syndrome…