Sleep advances : a journal of the Sleep Research Society最新文献

The "sleep to forget and sleep to remember" hypothesis states that sleep attenuates the emotional tone of a memory while strengthening its factual content. However, previous experimental research has yielded inconsistent results, associating sleep with the reduction, enhancement, or maintenance of the emotional tone of memories. Although the hypothesized process may necessitate multiple nights of sleep, most studies have relied on single-night protocols. To address this, we further investigated whether immediate sleep diminishes emotional reactivity triggered by memory reactivation after one week. In a karaoke paradigm, we recorded participants' singing of two songs and played back one of their recordings (rec1) to induce an embarrassing episode either in the early afternoon (delayed sleep group; N = 25) or the evening (immediate sleep group; N = 25). One week later, we assessed participants' emotional reactions to the re-exposed recording (rec1) and a newly introduced recording (rec2). Emotional reactivity was assessed using facial blushing as a primary physiological measure and subjective ratings of embarrassment, valence, and blushing. Sleep was monitored using diaries. While the embarrassing episode was successfully induced, Bayesian mixed-effects models revealed reduced facial blushing and more negative valence ratings from initial exposure to re-exposure (rec1) after both a shorter and longer interval to sleep. These changes were nonspecific to the reactivated recording (rec1) and were also observed for the new recording (rec2). Other subjective measures remained unchanged. This study demonstrates that neither the time interval to sleep following encoding nor memory reactivation influenced long-term emotional reactivity, leaving sleep's role in emotional memory processing elusive.

The manual evaluation of mouse sleep studies is labor-intensive and time-consuming. Although several approaches for automatic sleep stage classification have been proposed, no automatic pipeline for detecting a specific mouse phenotype has yet been developed. Here, we present a fully automated pipeline for estimating the probability of Narcolepsy Type 1 (NT1) in the hypocretin-tTA;TetO-Diphteria toxin A (DTA) mouse model using unlabeled electroencephalographic (EEG) and electromyographic (EMG) data. The pipeline is divided into three modules: (1) automatic sleep stage classification, (2) feature extraction, and (3) phenotype classification. We trained two automatic sleep stage classifiers, Usleep_EEG and Usleep_EMG, using data from 83 wild-type (WT) mice. We next computed features such as EEG spectral power bands, EMG root mean square, and bout metrics from 11 WT and 19 DTA mice. The features were used to train an L1-penalized logistic regression classifier in a Leave-One-Subject-Out approach, achieving an accuracy of 97%. Finally, we validated the pipeline in a held-out dataset of EEG/EMG recordings at four different timepoints during disease development in seven DTA mice, finding that the pipeline captured disease progression in all mice. While our pipeline generalizes well to data from other laboratories, it is sensitive to artifacts, which should be considered in its application. With this study, we present a pipeline that facilitates a fast assessment of NT1 probability in the DTA model and thus can accelerate large-scale evaluations of NT1 treatments.

Study objectives: Unfamiliar environments are often poorly conducive to quality sleep, especially for patients within health and aged care settings. This scoping review aims to map available evidence regarding the sleep environment in rehabilitation, subacute, and aged care settings. It examines how these factors are measured and seeks to identify any reported standard metrics, guidelines, or methodologies.

Methods: Searches were conducted within PubMed, EMBASE, Cochrane Library, Cumulated Index to Nursing and Allied Health Literature, PsycINFO, and Web of Science from database inception to May 2023. Eligibility criteria included original studies of any design reporting on the measurement properties of care environment factors affecting the sleep of adult patients admitted to rehabilitation, subacute wards, and aged care facilities.

Results: Seventy-four studies were reviewed that included 5055 participants, mostly (78.4%, 58/74) from aged care facilities. From 102 identified care environment factors, the spectral measurements of light were most reported (65.7%, 67/102), with methodologies varying from actigraphy and illuminance meters to pendant-style light monitors. Other environmental factors (sound, temperature, and air quality/humidity), room characteristics (mattress/bedding, room cohabitation), and hospital functioning (imposed schedules) were measured considerably less often and displayed similar variations in reported units and devices. Eighteen studies reported international, national, and methodological standards or guidelines.

Conclusions: This review provides a comprehensive overview of the care environment factors affecting sleep studied within rehabilitation, subacute, and aged care settings. Various units and devices were used in measuring these factors, and standard metrics and methodology were not consistently used. Future care environment studies incorporating interventions that employ standardized devices, units, and methodologies, will thereby enhance the reliability and comparability of findings within this field.

Aging is associated with disruptions in circadian rhythms, lower brain white matter integrity, and cognitive changes. However, whether white matter integrity serves as a potential mechanism linking circadian dysfunction to age-related cognitive abilities in older adults is unclear. We investigated cross-sectional associations of actigraphic circadian rest/activity rhythms (RARs) with whole-brain white matter tract fractional anisotropy (FA) and executive function performance in 156 older adults without dementia from the BIOCARD study (mean age = 71.3 years, including 19 with mild cognitive impairment and 137 cognitively unimpaired). We studied non-parametric metrics of RAR strength (relative amplitude [RA]), day-to-day stability (interdaily stability [IS]), and fragmentation (intradaily variability [IV]). After adjusting for age, sex, education, APOE-e4 genotype, vascular risk, and diagnostic group, we found that greater rhythm strength (higher RA) was associated with better executive function. Additionally, higher rhythm strength (RA) and stability (IS) were associated with greater whole-brain FA, reflecting better white matter integrity, whereas greater fragmentation (IV) was associated with lower FA. Greater white matter integrity was also associated with better executive function and statistically mediated the association of higher RA with better executive function performance. Findings underscore the relationships between RAR strength and cognitive health in older adults and suggest that white matter integrity may be a key mechanism underlying these associations.

Story retelling is an important form of communication, cultural practice, and message transmission. Insufficient sleep is known to affect relevant cognitive skill areas necessary for story retelling or transmission fidelity. We conducted a preregistered randomized cross-over study on n = 155 young adults with exogenously assigned nightly sleep levels experienced in their at-home environments. A serial story reproduction task was administered online, and chains of up to three retells of a given story involved varied numbers of sleep restricted (SR) versus well-rested (WR) retellers. While story content decayed with each retell, group-level analysis showed that additional SR retellers in a chain was associated with greater decay, which mostly resulted from the introduction of an initial SR reteller at the first retell. Supporting the group-level effect, individual-level analysis confirmed that the number of details and the story's key event were significantly less preserved during a participant's SR treatment week. Exploratory analysis showed an attenuation of this effect in those reporting a higher level of affective response (interest or surprise) in the story. This suggests that emotional engagement can combat the deleterious effects of SR on successful story retelling, and perhaps on other types of content recollection.

Study objectives: The microbiome is proposed as a contributor to the adverse health impacts from altered sleep. The oral microbiome is a multifaceted microbial community that influences many health functions. However, data on the relationship between sleep and the oral microbiome are limited, and no studies have incorporated lifestyle and environmental exposures.

Methods: Within a subset (N=1,139) of the NIH-AARP cohort, we examined the association between self-reported sleep duration and the oral microbiome via 16S rRNA gene amplicon sequencing. Statistical models were adjusted for demographic characteristics. Additional models examined the role of various lifestyle and neighborhood exposures on the sleep-oral microbiome association.

Results: Compared to participants reporting the recommended 7-8 hours average sleep duration (n=702), those reporting short sleep (6 or fewer hours, n=284) had consistently decreased within-sample oral microbial diversity [e.g. number of observed amplicon sequence variants difference -8.681, p-value=0.009]. Several bacterial genera were more likely to be absent in the short sleep group. We found a higher relative abundance of Streptococcus and Rothia, and lower abundance of Fusobacterium, Atopobium, and Campylobacter in the short compared to the recommended sleep duration group. Results were consistent when controlling for lifestyle and neighborhood factors.

Conclusions: Our findings provide evidence for an association of short sleep duration with oral microbial diversity and composition. This suggests that oral bacteria may play a possible mechanistic role related to sleep health. Improved understanding of physiological pathways can aid in the design of interventions that may beneficially improve overall sleep health.

I review the path of my career in sleep. My focus has been on the need for sleep and the relationship between sleep and performance. I have done sleep research in the sleep lab setting and have also taken unique opportunities to measure sleep loss effects on real-world performance. My studies have included long and short sleeper studies, evaluations of various sleep aids, sleep loss effects, jet lag effects, naps, and the consequences of being a poor sleeper. Over the course of my career in sleep, I have also taught about sleep in university and professional educational settings. I am a Board Certified Sleep Medicine Specialist with a private practice, providing diagnosis and treatment of sleep disorders in children and adults.

Sleep disorders are prevalent in shift workers but are commonly undiagnosed and unmanaged. This poses considerable safety, productivity, and health risks. There is limited education or early intervention to encourage awareness of, and treatment for, sleep disorders in young adults who will transition into careers requiring shift work. This study aims to investigate (a) the clinical effectiveness of simulated shift work exposure and cognitive performance feedback for prompting help-seeking for sleep problems, and (b) the feasibility and acceptability of implementing this intervention for future healthcare workers. A hybrid type I effectiveness-implementation trial will be conducted from June 2024 to December 2025 with prospective healthcare workers currently enrolled in a medicine, paramedicine, or nursing degree. Ninety adults (18-39 years) who self-report sleep disturbances will be recruited and complete a combination of structured clinical interviews, screening questionnaires, remote monitoring technology, and overnight polysomnography (PSG). Participants will be randomized across three conditions, with varying exposure to a simulated transition to night shift without sleep, and cognitive performance feedback. All individuals will attend a diagnostic appointment with a sleep psychologist or sleep physician and discuss help-seeking pathways for their sleep. The primary outcomes will be help-seeking from a health professional for sleep (yes/no), time to help-seeking (days), and road safety-related events over 12 months. Process evaluation will explore the feasibility and acceptability of this approach from the participants' perspective.

With the increase in life expectancy and the rapid evolution of daily life technologies, older adults must constantly learn new skills to adapt to society. Sleep reinforces skills acquired during the day and is associated with the occurrence of specific oscillations such as spindles. However, with age, spindles deteriorate and thus likely contribute to memory impairments observed in older adults. The application of electric currents by means of transcranial alternating current stimulation (tACS) with spindle-like waveform, applied during the night, was found to enhance spindles and motor memory consolidation in young adults. Here, we tested whether tACS bursts inspired by spindles applied during daytime naps may (i) increase spindle density and (ii) foster motor memory consolidation in older adults. Twenty-six healthy older participants performed a force modulation task at 10:00, were retested at 16:30, and the day after the initial training. They had 90-minute opportunity to take a nap while verum or placebo spindle-inspired tACS bursts were applied with similar temporal parameters to those observed in young adults and independently of natural spindles, which are reduced in the elderly. We show that the density of natural spindles correlates with the magnitude of memory consolidation, thus confirming that spindles are promising physiological targets for enhancing memory consolidation in older adults. However, spindle-inspired tACS, as used in the present study, did not enhance either spindles or memory consolidation. We therefore suggest that applying tACS time-locked to natural spindles might be required to entrain them and improve their related functions.