Clin. Transl. Neurosci., Volume 8, Issue 1 (March 2024) – 15 articles

Many patients with cluster headaches report that their relatives do not understand what they are going through. This qualitative study aimed to collect patients’ recommendations and wishes on how others should respond to those suffering from cluster headaches. We recruited 22 patients with episodic or chronic cluster headaches for this cross-sectional study. They responded to seven questions that assessed the disease’s impact on their relationships with relatives and their wishes for others’ behaviour towards them. Seven recommendations for relatives emerged: (i) withdraw during attacks, (ii) respect post-ictal exhaustion, (iii) do not insist on discussing the disorder, (iv) help the patient to lead a “normal” life, (v) support preserving social contacts, (vi) show being aware of the disease severity, and (vii) expect the disease to take up space in patients’ lives and minds. Two recommendations for the interictal period indicate avoidance, which is considered a negative coping strategy. Conversely, the suggestion to support preserving social contacts might mean confronting the disease, which is likely associated with more favourable outcomes. Still, adhering to all patients’ requests might increase suffering instead of reducing it. Thus, further research is needed to develop strategies suited to improve well-being. Full article

Sleep is essential for health, well-being, creativity, and productivity. Sleep loss and sleep–wake circadian disorders (SWCDs) affect at least one in three individuals but are underdiagnosed and undertreated for different reasons: First, the importance of sleep health and, second, the burden of sleep loss and SWCDs are underestimated. Third, education in sleep medicine is insufficient and health care-related sleep research is underdeveloped. Fourth, the validation and implementation of tele-sleep medicine approaches and novel devices to monitor SWCDs are still insufficient. Fifth, the reimbursement of sleep medicine in most countries is inadequate and the availability of specialized care is limited to a few centers. The Swiss Sleep House Bern (SSHB) was founded in 2022 to address these challenges and eventually promote better care for patients with SWCDs and improve sleep health for the broader population. The interdisciplinary and interprofessional team of the SSHB, which is integrated in the Bernese Interdisciplinary Sleep-Wake-Epilepsy Center, links sleep specialists with primary care providers to offer a rapid and accessible triage and first-level management of sleep complaints and SWCDs. The SSHB also promotes awareness and offers educational programs on sleep health and SWCDs, performs health care research, and fosters the implementation of new technologies, data science, and telemedicine into clinical routine. Full article

The field of sleep research is both broad and rapidly evolving. It spans from the diagnosis of sleep-related disorders to investigations of how sleep supports memory consolidation. The study of sleep includes a variety of approaches, starting with the sole focus on the visual interpretation of polysomnography characteristics and extending to the emergent use of advanced signal processing tools. Insights gained using artificial intelligence (AI) are rapidly reshaping the understanding of sleep-related disorders, enabling new approaches to basic neuroscientific studies. In this opinion article, we explore the emergent role of AI in sleep research, along two different axes: one clinical and one fundamental. In clinical research, we emphasize the use of AI for automated sleep scoring, diagnosing sleep-wake disorders and assessing measurements from wearable devices. In fundamental research, we highlight the use of AI to better understand the functional role of sleep in consolidating memories. While AI is likely to facilitate new advances in the field of sleep research, we also address challenges, such as bridging the gap between AI innovation and the clinic and mitigating inherent biases in AI models. AI has already contributed to major advances in the field of sleep research, and mindful deployment has the potential to enable further progress in the understanding of the neuropsychological benefits and functions of sleep. Full article

Recently, it has become increasingly clear that there is a bidirectional relationship between sleep/circadian rhythms and neurodegeneration. Knowledge about this topic further improved after the description of the glymphatic system, which is mainly active during sleep. Changes in sleep and circadian rhythms are present not only in overt neurodegenerative diseases but also in their early, prodromal, and preclinical phases, supporting that they precede (and contribute to) the development of neurodegeneration. This narrative review provides a brief overview of sleep and circadian rhythm disruption in neurodegeneration, highlights the bidirectional relationship between sleep changes and neurodegeneration, and addresses future perspectives, in particular, whether sleep changes are able to predict neurodegeneration and the potential sleep actionability to prevent or modulate the development of neurodegenerative diseases. Full article

The last ten years have seen the development and publication of numerous national and international guidelines devoted to the diagnosis and treatment of insomnia. These include guidelines by the American College of Physicians (ACP), the American Academy of Sleep Medicine (AASM), the British Sleep Society (BSS), the German Sleep Society (GSS), and the European Sleep Research Society (ESRS). Though coming from very diverse authors and backgrounds, these guidelines by and large agree concerning the therapeutic recommendations: cognitive behavioral treatment of insomnia (CBT-I), a multicomponent psychotherapeutic intervention, is unequivocally recommended as a first-line treatment. In this report, we will focus on the most recent guideline update from the ESRS, which was published in November 2023. After suggesting a careful diagnostic procedure, CBT-I, both applied face to face (F2F) or digitally (dCBT-I), is again recommended as a first-line treatment based on the available evidence. Hypnotic medications like benzodiazepines (BZ), benzodiazepine receptor agonists (BZRA), sedating antidepressants, and others are approved for short-term-treatment of up to four weeks. Orexin receptor antagonists (i.e., daridorexant) and prolonged release melatonin are considered as options for longer-term treatment when carefully considering the advantages and disadvantages. Both light therapy and exercise regimens were viewed as promising; however, they still lack convincing evidence for the time being. Given the fact that not every patient responds satisfactorily or even remits following CBT-I or other treatment options, the research agenda calls for the development and evaluation of new therapeutic avenues and combination therapies. Full article

When we are asleep, we lose the ability to promptly respond to external stimuli, and yet we spend many hours every day in this inherently risky behavioral state. This simple fact strongly suggests that sleep must serve essential functions that rely on the brain going offline, on a daily basis, and for long periods of time. If these functions did not require partial sensory disconnection, it would be difficult to explain why they are not performed during waking. Paradoxically, despite its central role in defining sleep and what sleep does, sensory disconnection during sleep remains a mystery. We have a limited understanding of how it is implemented along the sensory pathways; we do not know whether the same mechanisms apply to all sensory modalities, nor do we know to what extent these mechanisms are shared between non-rapid eye movement (NREM) sleep and REM sleep. The main goal of this contribution is to review some knowns and unknowns about sensory disconnection during sleep as a first step to fill this gap. Full article

Together with (physical and mental) exercise, diet, and social activities, sleep is a key health behavior that occupies one third of our lives, yet remains neglected. In the first part of this review, we present the current knowledge on how sleep promotes body, brain, mental, occupational, and social health as well as creativity, productivity, and well-being. In the second part, we discuss how good sleep and screening for sleep–wake disorders may improve health and reduce the burden of brain, mental, cardiovascular, metabolic disorders and cancer. We also review the literature on measurements of sleep health and present the Bernese Sleep Health Questionnaire, a new and simple tool to assess sleep health and screen for sleep–wake circadian disorders in clinical practice. Full article

A growing body of literature demonstrates a critical role for sleep in upregulating diverse biological processes related to protein synthesis, immune function, and cellular housekeeping such as intracellular transport and membrane repair. The energy allocation (EA) hypothesis places sleep in a broader context of resource optimization where sleep–wake partitioning of metabolic operations optimizes resource utilization. The EA hypothesis of sleep carries important implications in health, disease, and homeostatic mechanisms. Specifically, conditions that lead to cellular stress, energy constraints or depression of neuronal activity, such as epilepsy, ischemic stroke or cortical spreading depression, are here proposed to follow similar conserved processes that favor sleep. This review examines the role of local mechanisms, including cytokine release or the accumulation of adenosine, in downregulating wakefulness to favoring sleep, loss of functional connectivity and the upregulation sleep-coupled processes that promote survival. Full article

The two-process model of sleep regulation has served as a conceptual framework in the last four decades for understanding sleep physiology. In the 1970s, long-term recordings of sleep in rats were obtained thanks to EEG telemetry. NonREM sleep and REM sleep were found to differ in their time course and response to light-dark protocols. There were indications for their coupling to the circadian system, in particular the light-dark and the dark-light transitions. With the advent of quantitative EEG analysis, slow-wave activity in nonREM sleep was recognized as a sleep-wake-dependent variable. The term “sleep homeostasis” was coined to specify the regulated balance between sleep and waking. The regulatory homeostatic process was designated as “Process S”. In the two-process model, its interaction with the circadian pacemaker “Process C” can account for sleep duration under various experimental protocols. Local, use-dependent slow-wave activity changes were demonstrated in both humans and rats by the selective, unilateral activation of a cortical region prior to sleep. Finding that rest in invertebrates has sleep-like regulatory properties opened a new realm of animal studies. Comparative sleep studies in a broad variety of animal species confirmed the validity of the basic concepts of the two-process model. Recent studies have addressed sleep-related changes of brain temperature as an indicator of brain metabolism; the application of the model to Drosophila; the divergence of cortical and subcortical states; and sleep in an increasing number of species and taxa. Full article

Adolescence is a pivotal period of development marked by significant physiological and psychological changes, making youth particularly susceptible to mental health challenges, including depression. A growing body of research has highlighted the important role of sleep in the etiology and exacerbation of adolescent depression. Disruptions in sleep patterns, including insomnia and irregular sleep-wake cycles, are prevalent among depressed adolescents and can exacerbate depressive symptoms. In this review, we examine alterations to sleep behavior and physiology in adolescent depression. Furthermore, we introduce a theoretical model of hypersomnia in adolescent depression. This manuscript explores the intricate relationship between sleep and adolescent depression, with a focus on future directions for research and intervention. Full article

Introduction and aims: Narcolepsy type 1 (NT1) is a central disorder of hypersomnolence (CDH) characterized by excessive daytime sleepiness and cataplexy. The Swiss Narcolepsy Scale (SNS), which includes the updated and short (sSNS) versions, has recently been introduced as a reliable diagnostic tool for identifying NT1. This study aims to assess the validity of the SNS scales in a new cohort of patients with CDH, while also introducing the French and Italian versions of the SNS and providing a summary of the existing literature on SNS. Materials and methods: The current study is based on the international Swiss Primary Hypersomnolence and Narcolepsy Cohort Study (iSPHYNCS) which aims to identify new biomarkers for CDH. Diagnostic accuracy of the SNS was assessed by calculating sensitivity, specificity, positive predictive value, and negative predictive value. Results: In our population, 108 participants with suspected CDH (including 28 NT1 patients) and 14 healthy controls completed the scale. Original SNS, updated SNS and sSNS scores showed a high sensitivity (86%, 89% and 79%, respectively) and high specificity (96%, 90% and 95%, respectively) for diagnosing NT1 compared to other CDH. The French version was completed by 5 participants, and the Italian version by 8 participants. Regarding previous studies, the SNS has now been assessed in six different populations, involving a total of 1247 subjects (including 326 with narcolepsy with cataplexy/NT1), suggesting high sensitivity (85–100%) and specificity (86–100%) of the SNS for the diagnosis of NT1. Conclusion: The SNS is a simple screening tool validated in seven languages (German, English, French, Italian, Dutch, Turkish and Japanese), demonstrating high sensitivity and specificity for the diagnosis of NT1. Full article

Sleep-related eating disorder (SRED) is a relatively rare but probably underestimated disorder, where affected patients exhibit nocturnal eating episodes with impaired consciousness and subsequent amnesia. SRED has originally been classified as NREM (non-rapid eye movement) parasomnia, with an obviously high number of concomitant sleep disorders. We suggest that SRED may represent a heterogenous disease, based on accumulating data in recent studies. Some SRED patients may be better classified as sleep-related movement disorders with an underlying dopaminergic dysfunction. Hypnotic drugs may play a crucial role in triggering amnestic SRED in both parasomnic and sleep-related movement-disordered SRED. Full article