Axel Steiger

Lucid dreaming (LD) is a state of conscious awareness of the ongoing oneiric state, predominantly linked to REM sleep. Progress in understanding its neurobiological basis has been hindered by small sample sizes, diverse EEG setups, and artifacts like saccadic eye movements. To address these challenges in characterizing the electrophysiological corr...

This valuable study provides a novel method to detect sleep cycles based on variations in the slope of the power spectrum from electroencephalography signals. The method, dispensing with time-consuming and potentially subjective manual identification of sleep cycles, is supported by solid evidence and analyses. This study will be of interest to res...

Sleep cycles are defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode of REM sleep. Fractal or aperiodic neural activity is a well-established marker of arousal and sleep stages measured using electroencephalography. We introduce a new concept of ‘fractal cycles’ of sleep, defined as a time interval during which time...

Nocturnal human sleep consists of 4 – 6 ninety-minute cycles defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode of REM sleep. While sleep cycles are considered fundamental components of sleep, their functional significance largely remains unclear. One of the reasons for a lack of research progress in this field is...

Nocturnal human sleep consists of 4 – 6 ninety-minute cycles defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode of REM sleep. While sleep cycles are considered fundamental components of sleep, their functional significance largely remains unclear. One of the reasons for a lack of research progress in this field is...

Sleep cycles are defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode of REM sleep. Fractal or aperiodic neural activity is a well-established marker of arousal and sleep stages measured using electroencephalography. We introduce a new concept of ‘fractal cycles’ of sleep, defined as a time interval during which time...

Nocturnal human sleep consists of 4 – 6 ninety-minute cycles defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode of REM sleep. While sleep cycles are considered fundamental components of sleep, their functional significance largely remains unclear. One of the reasons for a lack of research progress in this field is...

Objective Recent evidence shows that during slow‐wave sleep (SWS), the brain is cleared from potentially toxic metabolites, such as the amyloid‐beta protein. Poor sleep or elevated cortisol levels can worsen amyloid‐beta clearance, potentially leading to the formation of amyloid plaques, a neuropathological hallmark of Alzheimer disease. Here, we e...

Lucid dreaming (LD) is a state of conscious awareness of the current dream state, predominantly associated with REM sleep. Research progress in uncovering the neurobiological basis of LD has been hindered by low sample sizes, diverse EEG setups, and specific artifact issues like saccadic eye movements and signal non-stationarity. To address these m...

Nocturnal human sleep consists of 4 – 6 ninety-minute cycles defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode of REM sleep. While sleep cycles are considered fundamental components of sleep, their functional significance largely remains unclear. One of the reasons for a lack of research progress in this field is...

Introduction: Nocturnal human sleep consists of 4–6 ninety-minute cycles defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode of REM sleep. While sleep cycles are considered fundamental components of sleep, their functional significance remains to a large extent unclear. One of the reasons for a lack of research prog...

Study Objectives Voluntary sleep restriction is a common phenomenon in industrialized societies aiming to increase time spent awake and thus productivity. We explored how restricting sleep to a radically polyphasic schedule affects neural, cognitive, and endocrine characteristics. Methods Ten young healthy participants were restricted to one 20-mi...

Voluntary sleep restriction is a common phenomenon in industrialized societies aiming to increase time spent awake and thus productivity. We explored how restricting sleep to a radically polyphasic schedule affects neural, cognitive, and endocrine characteristics. Ten young healthy participants were restricted to one 30-min nap opportunity at the e...

Background: Recent evidence shows that during slow-wave sleep (SWS), the brain is cleared from potentially toxic metabolites, such as the amyloid-beta protein. Poor sleep or elevated cortisol levels can worsen amyloid-beta clearance, potentially leading to the formation of amyloid plaques, a neuropathological hallmark of Alzheimer's disease. Here,...

Supplementary Material for "Divergent associations of slow-wave sleep vs. REM sleep with plasma amyloid-beta"

Sleep disturbances are frequent complaints in patients with mental health disorders. Traditionally, disrupted sleep is regarded as a symptom or nonspecific epiphenomenon only temporally associated with the disorders. Consequently, the treatment of sleep problems is often disregarded in clinical and psychiatric practice. However, there is increasing...

Disturbed sleep is a key symptom in major depressive disorder (MDD). REM sleep alterations are well described in the current literature, but little is known about non-REM sleep alterations. Additionally, sleep disturbances relate to a variety of cognitive symptoms in MDD, but which features of non-REM sleep EEG contribute to this, remains unknown....

Background In major depressive disorder (MDD), patients often express subjective sleep complaints while polysomnographic studies report only subtle alterations of the electroencephalographic (EEG) signal. We hypothesize that differentiating the signal into its oscillatory and aperiodic components may bring new insights into our understanding of sle...

Background In major depressive disorder (MDD), patients often express subjective sleep complaints while polysomnographic studies report only subtle alterations in neural oscillations. We hypothesize that the study of aperiodic electroencephalographic (EEG) dynamics, a marker of excitation-to-inhibition balance, may bring new insights into our under...

Disturbed sleep is a key symptom in major depressive disorder (MDD). REM sleep alterations are well described in the current fliterature, but little is known about non-REM sleep alterations. Additionally, sleep disturbances relate to a variety of cognitive symptoms in MDD, but which features of non-REM sleep EEG contribute to this, remains unknown....

Mnemonic techniques, such as the method of loci, can powerfully boost memory. We compared memory athletes ranked among the world’s top 50 in memory sports to mnemonics-naïve controls. In a second study, participants completed a 6-week memory training, working memory training, or no intervention. Behaviorally, memory training enhanced durable, longe...

Features of sleep were shown to reflect aging, typical sex differences and cognitive abilities of humans. However, these measures are characterized by redundancy and arbitrariness. Our present approach relies on the assumptions that the spontaneous human brain activity as reflected by the scalp-derived electroencephalogram (EEG) during non-rapid ey...

Indikationen, Wirkungsweise, Nebenwirkungen und Risiken, Kontraindikationen und Interaktionen werden für die Medikamente gegen Schlafstörungen beschrieben. Diese werden entsprechend den DSM-5- und ICD11-Kriterien neu geordnet. Die Strukturen innerhalb der einzelnen Diagnosen sind geblieben.

Sleep consists of an electrophysiological and a neuroendocrine component. Their interaction was investigated in healthy volunteers of both sexes throughout the lifespan, in patients with various disorders, after manipulation of the sleep–wake pattern and after administration of synthetic and endogenous substances acting at the central nervous syste...

It is already known that during normal sleep plasma renin activity (PRA) shows oscillations with decreases during rapid-eye-movement (REM) sleep and increases during non-REM (NREM) sleep. We also know that renin correlates positively with slow-wave sleep (SWS). Sleep deprivation is known to enhance significantly SWS and slow wave activity (SWA, kno...

Lucid dreaming—the phenomenon of experiencing waking levels of self-reflection within one’s dreams—is associated with more wake-like levels of neural activation in prefrontal brain regions. In addition, alternating periods of wakefulness and sleep might increase the likelihood of experiencing a lucid dream. Here we investigate the association betwe...

Sleep disturbances are prevalent in both patients with pituitary insufficiency and with depression. The role of corticotropin releasing hormone (CRH), involved in sleep regulation, has not been fully clarified. Pituitary insufficiency is an ideal model for studying sleep-endocrine effects since no consecutive hormone releases and feedback effects o...

Mnemonic techniques, such as the method of loci, can powerfully boost memory. Here, we compared memory athletes ranked among the world's top 50 in memory sports to mnemonics-naive controls. In a second study, participants completed a six-weeks memory training, working memory training, or no intervention. Behaviorally, memory training enhanced durab...

A novel method for deriving composite, non-redundant measures of non-rapid eye movement (NREM) sleep electroencephalogram (EEG) is developed on the basis of the power law scaling of the Fourier spectra. Measures derived are the spectral intercept, the slope (spectral exponent), as well as the maximal whitened spectral peak amplitude and frequency i...

The activation of the hypothalamus-pituitary-adrenal (HPA) axis is induced by stress. Imbalances in this system increase the risk of developing stress related disorders including mental illness. Variants in the single nucleotide polymorphism (SNP) rs110402 of the corticotropin-releasing hormone receptor type I (CRHR1) gene have been shown in intera...

Slow wave activity is a hallmark of deep NREM sleep. Scalp slow wave morphology is stereotypical, it is highly correlated with the synchronized onset and cessation of cortical neuronal firing measured from the surface or depth of the cortex. It is also strongly affected by ageing, and these changes are causally associated with age-related cognitive...

Primary aldosteronism is a natural model for chronic aldosterone excess in humans and associated with symptoms of anxiety and depression. Cognitive deficits are inherent to the symptomatology of depression and anxiety disorders. Mineralocorticoid receptors and aldosterone appear to play a role in memory. Aldosterone was additionally supposed to be...

Variations in the anatomical and functional connectivity between brain areas underlie both healthy and pathological variation in psychological measures. Largely independent from external stimuli, the sleep EEG is particularly well suited to measure individual variations in functional brain connectivity. In this study of 172 healthy individuals (17-...

The mineralocorticoid receptor (MR)/glucocorticoid receptor balance plays an important role in the pathophysiology of anxiety and depression. Aldosterone, a primary MR ligand, seems to be related to the pathophysiology of anxiety and depressive symptoms. The objective of this study was to investigate effects of aldosterone excess on sleep EEG, as s...

Impaired sleep is both a risk factor and a symptom of depression. Objective sleep is assessed using the sleep electroencephalogram (EEG). Characteristic sleep-EEG changes in patients with depression include disinhibition of rapid eye movement (REM) sleep, changes of sleep continuity, and impaired non-REM sleep. Most antidepressants suppress REM sle...

Indikationen, Wirkungsweise, Nebenwirkungen und Risiken, Kontraindikationen und Interaktionen werden für die Medikamente gegen Schlafstörungen beschrieben. Diese werden entsprechend den DSM-5-Kriterien neu geordnet. Die Strukturen innerhalb der einzelnen Diagnosen sind geblieben.

Klein - leicht - Pocket Guide! Die schnelle und zuverlässige Info für die Kitteltasche - Psychopharmaka von A bis Z. Die überarbeitete und aktualisierte Version des Pocket Guide ist eine sinnvolle Ergänzung zum "Kompendium der psychiatrischen Pharmakotherapie" und beantwortet alle Fragen rund um die Psychopharmakotherapie. Ganz bewusst verzichtet d...

Slow wave activity is a hallmark of deep NREM sleep. Scalp slow wave morphology is stereotypical, it is highly correlated with the synchronized onset and cessation of cortical neuronal firing measured from the surface or depth of the cortex, strongly affected by ageing, and these changes are causally associated with age-related cognitive decline. W...

Context: The loss of progesterone during menopause is linked to sleep complaints of the affected women. Previously we demonstrated sleep promoting effects of oral progesterone replacement in postmenopausal women. The oral administration of progesterone, however, is compromised by individual differences in bioavailability and metabolism of the ster...

Variance in spatial abilities are thought to be determined by in utero levels of testosterone and oestrogen, measurable in adults by the length ratio of the 2nd and 4th digit (2D:4D). We confirmed the relationship between 2D:4D and spatial performance using rats in two different tasks (paired-associate task and watermaze) and replicated this in hum...

Changes in sleep-EEG after endocrine stimulation tests in patients with schizophrenia include reduced sleep efficiency, prolonged sleep latency and increased awaking after sleep onset Findings on sleep associated growth hormone (GH) secretion were ambiguous. The aim of this study was to elucidate the sleep-endocrine activity especially in the GH sy...

The shape of the EEG spectrum in sleep relies on genetic and anatomical factors and forms an individual "EEG fingerprint". Spectral components of EEG were shown to be connected to mental ability both in sleep and wakefulness. EEG sleep spindle correlates of intelligence, however, exhibit a sexual dimorphism, with a more pronounced association to in...

A single nucleotide polymorphism substitution from glutamine (Gln, Q) to arginine (Arg, R) at codon 460 of the purinergic P2X7 receptor (P2X7R) has repeatedly been associated with mood disorders. The P2X7R-Gln460Arg variant per se is not compromised in its function. However, heterologous expression of P2X7R-Gln460Arg together with wild-type P2X7R h...

Variance in spatial abilities are thought to be determined by in utero levels of testosterone and oestrogen, measurable in adults by the length ratio of the 2 nd and 4 th digit (2D:4D). We confirmed the relationship between 2D:4D and spatial performance using rats in two different tasks (paired-associate task and watermaze) and replicated this in h...

Objectives: The relevance of rapid eye movement (REM) sleep in affective disorders originates from its well-known abnormalities in depressed patients, who display disinhibition of REM sleep reflected by increased frequency of rapid eye movements (REM density). In this study we examined whether heart rate variability (HRV) and prefrontal theta cord...

Females and males differ in several features of their spindle oscillations, as well as in the hemispheric lateralization of their neurocognitive processes. In addition, the hemispheric lateralization of cognitive functions was shown to vary in an age-dependent manner. In spite of the above knowledge, data on the hemispheric lateralization of these...

Females and males differ in several features of their spindle oscillations, as well as in the hemispheric lateralization of their neurocognitive processes. In addition, the hemispheric lateralization of cognitive functions was shown to vary in an age-dependent manner. In spite of the above knowledge, data on the hemispheric lateralization of these...

Dieses komprimierte Pocket-Buch ist bestens geeignet, um es in die Kitteltasche zu packen. Die Informationen im Buch sind sehr knapp und präzise gehalten; ganz bewusst wurde hier auf eine ausführliche Darstellung der Störungen verzichtet. Im Pocket Guide finden Sie von A bis Z schnell und übersichtlich die "Erste-Hilfe"-Information rund um alle Psy...

Der Begriff Schlafstörungen wird im DSM-5 durch Schlaf-Wach-Störungen ersetzt. Es werden 10 Störungen bzw. Störungsgruppen unterschieden, von denen die für die Psychopharmakologie relevanten in diesem Kapitel aufgeführt werden. Dabei werden hier zunächst die Insomnie, die Narkolepsie und das Restless-Legs-Syndrom dargestellt, für die definierte Med...

We reported previously that repetitive intravenous injections of corticotropin-releasing hormone (CRH) around sleep onset prompt depression-like changes in certain sleep and endocrine activity parameters (e.g. decrease of slow-wave sleep during the second half of the night, blunted growth hormone peak, elevated cortisol concentration during the fir...

Impaired sleep is a frequent complaint in ageing and a risk factor for many diseases. Non-rapid eye movement (NREM) sleep EEG delta power reflects neural plasticity and, in line with age-related cognitive decline, decreases with age. Individuals with higher general intelligence are less affected by age-related cognitive decline or other disorders a...

Ghrelin regulates energy homeostasis in various species and enhances memory in rodent models. In humans, the role of ghrelin in cognitive processes has yet to be characterized. Here we show in a double-blind randomized crossover design that acute administration of ghrelin alters encoding-related brain activity, however does not enhance memory forma...

The ability to consolidate procedural memories declines with increasing age. Prior knowledge enhances learning and memory consolidation of novel but related information in various domains. Here, we present evidence that prior motor experience-in our case piano skills-increases procedural learning and has a protective effect against age-related decl...

Learning model. To fit the learning curves, we used a hierarchical Bayesian model. The learning curves are fully characterized by three parameters: I the initial performance, C the change from the initial performance to the asymptote on day one and R the learning rate indicating how quickly asymptotic performance is reached; Y is the performance in...

Box plots for the ages in the younger and older group. The red line indicates the mean age; the box contains 50% of the data starting from the 25th percentile ranging to the 75th percentile. The whiskers extend from the 25th or 75th percentile to the farthest data point that is not an outlier (i.e. >1.5 times the length of the box away from either...

Supplemental Methods, Discussion, Results and Refences. The supplemental material contains more details on the sampled ages in the study, the utilized learning model, additional control analysis, and additional discussion of the interaction of gender and piano experience as well as the Appropriateness of the fingertapping task as a model for playin...

Supplemental Data Control Experiment 1. The raw data from the first Control experiment. (XLSX)

Supplemental Data Control Experiment 2. The raw data from the second Control experiment. (XLSX)

Sleep is a time of high activity in endocrine systems. Accordingly there is a bidirectional interaction between the non-REM-REM cycle which is recorded electrophysiologically and the patterns of secretion of hormones. Certain hormones participate in sleep regulation. In this issue a reciprocal interaction of the neuropeptides growth hormone-releasi...

Es wird die Neurobiologie und die Therapie der verschiedensten Schlafstörungen, insbesondere Insomnie und Hypersomnie, beschrieben.

Vorerst wird der bewährte Begriff »Schlafstörung« beibehalten. Für die Untergruppen Insomnien, Hypersomnien und Restless-Legs-Syndrom stehen definierte Medikamentengruppen zur Verfügung, für weitere Gruppen nur Therapieempfehlungen aus Fallstudien.

Creativity is one of the most valued cognitive traits and the driver of human culture. However, little is known about its psychological and neurobiological basis – partly because originality and uniqueness as essential characteristics of creativity are elusive topics when it comes to systematic research. Historical anecdotes, theoretical considerat...

Sleep spindles are thalamocortical oscillations in non-rapid eye movement (NREM) sleep, that play an important role in sleep-related neuroplasticity and offline information processing. Several studies with full-night sleep recordings have reported a positive association between sleep spindles and fluid intelligence scores, however more recently it...

Mounting evidence for the role of sleep spindles in neuroplasticity has led to an increased interest in these non-rapid eye movement (NREM) sleep oscillations. It has been hypothesized that fast and slow spindles might play a different role in memory processing. Here, we present a new sleep spindle detection algorithm utilizing a continuous wavelet...

Axel Steiger, Marcel Pawlowski, Mayumi Kimura Max Planck Institute of Psychiatry, Munich, Germany Abstract: The sleep electroencephalogram (EEG) provides biomarkers of depression, which may help with diagnosis, prediction of therapy response, and prognosis in the treatment of depression. In patients with depression, characteristic sleep EEG changes...

Many young females take exogenous hormones as oral contraceptive (OC), a condition rarely controlled for in studies on sleep and memory consolidation even though sex hormones influence consolidation. This study investigated the effects of OCs on sleep-related consolidation of a motor and declarative task, utilizing a daytime nap protocol. Fifteen h...

Sleep spindles are frequently studied for their relationship with state and trait cognitive variables, and they are thought to play an important role in sleep-related memory consolidation. Due to their frequent occurrence in NREM sleep, the detection of sleep spindles is only feasible using automatic algorithms, of which a large number is available...

Sleep problems are a common complaint in the majority of people suffering from depression. While sleep complaints were traditionally seen as a symptom of mood disorders, accumulating evidence suggests that in many cases the relationship may be reverse as well. A long list of longitudinal studies shows that sleep complaints often precede the onset o...