Cognitive Performance, Sleepiness, and Mood in Partially Sleep Deprived Adolescents: The Need for Sleep Study

Sleep Time and Depression Symptoms as Predictors of Cognitive Development Among Adolescents: A Cross-Lagged Study From China

Sleep time and depression symptoms are important factors affecting cognitive development in adolescents. Based on the China Education Panel Survey (CEPS) database, this study used a two-wave cross-lagged model to examine the bidirectional relationship between sleep time, depression symptoms, and cognitive development. Descriptive statistics showed that Chinese adolescents' cognitive development increased significantly from 7th to 8th grade in junior high school, but unfortunately, their depression level and average sleep time per night demonstrated a slightly deteriorating trend. Correlation analysis showed that there was a relatively stable negative correlation between cognitive development, sleep time, and depression symptoms. Moreover, the cross-lagged model revealed that there was a bidirectional relationship between cognitive development and sleep time, a bidirectional relationship between depression symptoms and sleep time, and a unidirectional relationship between depression symptoms and cognitive development. Male adolescents in the subgroup were consistent with the total sample. Among female adolescents, only cognitive development and sleep time have a bidirectional relationship, while depression symptoms and cognitive development, and depression symptoms and sleep time have a unidirectional relationship. Therefore, it is of significance to take targeted action to promote cognitive development and healthy growth in adolescents worldwide.

Mediating Effects of Executive Function on the Relationship between Sleep Problems and Emotional and Behavioral Problems among Preschoolers: Physical Activity as a Protective Factor

This study investigated three waves of data from the Anhui Preschool Children Cohort study, with a total of 1,987 mother-child dyads participating. The questionnaires on sleep problems (Wave 1), executive function (EF) (Wave 2), physical activity (PA) (Wave 2), and emotional and behavioral problems (EBPs) (Wave 1 & Wave 3) were assessed by the mothers of the children. Results showed that sleep problems, GEC (total executive dysfunction scores), and PA are all positively related to EBPs. After controlling for covariates, GEC partially mediated the association between sleep problems and EBPs (β = 0.015, 95%CI: 0.002-0.028). PA moderated the relationship between sleep problems and preschoolers' GEC (β = -0.06, P<0.05). These findings reveal the mediating role of executive dysfunction in the association between sleep problems and EBPs. It also highlights that targeted interventions to reduce sleep problems and increase PA could help reduce the risk of EBPs in preschoolers.

Prenatal and Childhood Phthalate Mixtures and Adolescent Sleep Health in the HOME Study

BACKGROUND

The biological mechanisms linking early life phthalate exposure with adverse behaviors and cardiometabolic conditions also impact sleep health, but whether early life exposure impacts adolescent sleep is unknown.

OBJECTIVES

We evaluated whether gestational and childhood urinary phthalate metabolite mixtures were associated with sleep characteristics during adolescence. We also examined periods of heightened susceptibility to individual phthalates.

METHODS

In the Health Outcomes and Measures of the Environment (HOME) Study (Cincinnati, Ohio; 2003-2006; n = 156 ), we quantified urinary metabolites of eight parent phthalate diesters during pregnancy (16- and 26-wk) and childhood (ages 1, 2, 3, 4, 5, 8, and 12 years). Using regression calibration approaches, we estimated average measurement error-corrected phthalate metabolite concentrations during pregnancy and childhood. We used wrist actigraphy to assess sleep characteristics for 1 wk among participants at age 12. Using quantile-based g-computation, we estimated covariate-adjusted differences in sleep efficiency (%), sleep fragmentation index scores (%), sleep duration (minutes) per quartile increase in all phthalate metabolite concentrations (ψ ), and weights indicating the contribution of each metabolite to ψ . Using multiple informant models, we examined whether associations between individual phthalate metabolites and sleep characteristics varied by timing of exposure.

RESULTS

Increasing all gestational phthalate metabolites by a quartile was associated with lower sleep efficiency [ψ = - 1.3 % ; 95% confidence interval (CI): - 2.4 , - 0.3 ] and higher sleep fragmentation (ψ = 1.6 % ; 95% CI: 0.3, 3.0); mono-n-butyl phthalate (MnBP) and di(2-ethylhexyl) phthalate (DEHP) metabolites contributed most to these relations. Higher childhood phthalate metabolite mixture quartiles were associated with shorter sleep duration (ψ = - 21 minutes; 95% CI: - 34 , - 9 ); monoethyl phthalate (MEP) and monocarboxyoctyl phthalate (MCOP) contributed most to this association. We found that higher DEHP metabolite concentrations during pregnancy were more strongly related to higher sleep fragmentation than childhood concentrations. In contrast, higher MEP and MnBP concentrations during childhood, but not pregnancy, were consistently associated with shorter sleep duration.

DISCUSSION

Phthalate metabolite concentrations during pregnancy and childhood were associated with poorer adolescent sleep health. https://doi.org/10.1289/EHP15221.

Daily fluctuations in adolescents' sleep predict next-day attention, sleepiness, and fatigue: an ecological momentary assessment study over 28 days

BACKGROUND

Current understanding of the associations between adolescents' daily sleep and daytime alertness and fatigue under naturalistically occurring restricted (school) and unrestricted (vacation) sleep opportunities is limited.

METHODS

A convenience sample of adolescents (n = 205; 54.1% females, Mage ± SD = 16.9 ± 0.87 years) completed daily measures of sleep, alertness, and fatigue over 28 days (2 weeks during school, and the subsequent 2-week vacation). Actigraphy and sleep diary total sleep time (TST) and sleep efficiency (SE) were measured. Participants self-reported sleepiness and fatigue every morning and afternoon, and completed a tablet-based, 3.2-min psychomotor vigilance task (PVT) every afternoon. Cross-lagged multilevel models tested daily TST and SE as predictors of next-day subjective sleepiness/fatigue and PVT performance. Between- (i.e., differences between individuals) and within-person associations (i.e., whether nights with higher-than-individual's-average TST/SE, predict next-day outcomes) were tested simultaneously. Covariates included previous-day outcome, day of the week, study day (1-28), school/vacation, chronotype, and sociodemographic variables.

RESULTS

Within-persons, higher-than-average TST and SE (both actigraphy and diary) predicted better next-day PVT performance (all p ≤ .006), and lower subjective sleepiness and fatigue the following morning and afternoon (all p ≤ .032). Between-persons, adolescents with higher overall diary SE had lower morning subjective sleepiness (p < .001) and fewer PVT false starts in the afternoon (p = 0.02).

CONCLUSIONS

Nights with longer- and higher-than-average sleep efficiency (both actigraphy and diary) predicted better daytime alertness and fatigue, both when examined objectively via sustained attention and via self-report. These findings are relevant for understanding the significance of sleep for adolescents' day-to-day alertness levels and fatigue, particularly in the context of classroom learning and road safety.

What are the consequences of musculoskeletal pain in adolescents? A critical qualitative systematic review and meta-synthesis

There is a paucity of research into the lived experiences of adolescents with musculoskeletal pain. This study synthesised the available qualitative research on musculoskeletal pain consequences in adolescents. CINAHL, EMBASE, MEDLINE, PsycINFO and Research Rabbit were searched, and a critical qualitative systematic review and meta-synthesis was performed (Prospero ID=476626). Screening and data extraction were completed in duplicate. Critical appraisal of included studies and level of confidence in the findings were assessed. A thematic synthesis approach was used to derive analytical themes. Twelve studies were included (n=213). Adolescents (age range 8-22 years) reported functional impediments that impacted daily living, mobility, school, socializing, and sleep. Distress and concern regarding movement, health, isolation, autonomy, support, healthcare experiences, and their future were also reported. Adolescents report complex and burdensome consequences of musculoskeletal pain. The functional impediments and the psychosocial impacts lead adolescents to feel distressed, isolated, and unsupported. Confidence in the findings according to the GRADE-CERQual assessment showed high, moderate and low confidence across the results. This knowledge can be used to develop meaningful communication and understanding in clinical encounters with adolescents, and provide focus for more impactful research, addressing the consequences reported by adolescents.

Comparative analysis of sleep deprivation models: Impacts on sleep architecture, emotional state, cognitive function, and biochemical indicators in male rats

Sleep deprivation significantly affects both physiological and psychological health, with various experimental models used to study these impacts. This study compares three sleep deprivation models-Modified Multiple Platform Method (MMPM), treadmill method, and p-chlorophenylalanine (PCPA) method-on key physiological, cognitive, and emotional parameters in male Sprague-Dawley rats. The rats were subjected to 72 hours of sleep deprivation using these methods, followed by behavioral, cognitive, physiological, and biochemical assessments. Results indicated that the treadmill and PCPA methods led to significant reductions in both NREM and REM sleep (P < 0.05), with the PCPA method showing the most severe emotional effects, including heightened anxiety and depressive behaviors (P < 0.001). Cognitive impairments were most pronounced in the MMPM and treadmill groups (P < 0.01). All sleep deprivation models showed signs of autonomic nervous system dysfunction, as reflected by elevated LF/HF ratios in heart rate variability assessments (P < 0.05). Neurochemical analysis revealed reductions in hypothalamic 5-HT, Glu, and GABA levels, with the MMPM and treadmill methods causing more pronounced decreases (P < 0.05). Additionally, IL-2 levels significantly decreased while TNF-α levels increased in sleep-deprived rats compared to controls (P < 0.05). These findings highlight the distinct physiological, emotional, and cognitive impacts of different sleep deprivation models, providing a basis for model selection in future studies.

BMAL1 rescued the hippocampus-dependent recognition memory induced by sleep deprivation

Sleep plays an important role in the process of memory. This study investigated the role of the circadian clock gene, BMAL1 of the master circadian clock in mediating the impairment of hippocampus-dependent recognition memory caused by sleep deprivation. After 4 weeks of sleep deprivation, the novel object recognitiontask was used to evaluate the recognition memory of mice, the expression levels of circadian clock genes, and Nrf2 and PKA/CREB/BDNF signal pathways were detected by Western blot, Realtime-qPCR, and immunofluorescence. The mice in the SD group exhibited a significant decrease in the duration of exploration of novel objects. The protein expression levels of PER1, PER2, CLOCK, and BMAL1, and PKA/CREB/BDNF pathway in the hippocampus of the SD group were significantly reduced, and the Nrf2-mediated anti-oxidative capacity was also compromised in the SD group. Moreover, these aberrations could be mitigated through compensation with BMAL1 in the SCN of the hypothalamus. Sleep deprivation resulted in a reduction in the expression of the core clock gene BMAL1 in the hippocampus, leading to an imbalance in the antioxidant system and damaging down-regulating the PKA/CREB/BDNF signal pathway that related to the proteins associated with recognition memory in the hippocampal synapse plasticity and oxidative stress, which could be reversed by overexpression compensation of BMAL1 in the SCN that might rely on the multi-synaptic neural projections to the hippocampus.

A Scoping Review of Sleep Disturbances in Children and Adolescents with Abdominal Pain Disorders

Objective/Purpose/Aim

Sleep disturbances have been implicated as contributors to chronic pain. We undertook this review to assess the current literature regarding sleep disturbances in youth with chronic abdominal pain. We assessed studies evaluating prevalence, pathophysiology, and/or outcomes to identify gaps in knowledge and to determine whether there is an evidential basis for sleep interventions in this population.

Materials and Methods

Utilizing Google Scholar, Pub Med, SCOPUS, and Embase, we searched using the terms "sleep disturbances" AND ("abdominal pain"/exp OR "abdominal pain") AND ([adolescent]/lim OR [school]/lim). Articles were included if they contained data regarding sleep disturbance prevalence, pathophysiology, or relationships to outcome. After two independent review, 32 manuscripts were included in this review.

Results

Based on their high prevalence (19-75% of abdominal pain cohorts), there is sufficient evidence to recommend routine screening for sleep disturbances in youth with chronic abdominal pain. There is a broad range of negative physiologic and emotional effects of sleep deprivation.

Conclusion

Sleep disturbances are common in youth with chronic abdominal pain. Sleep interventions are appropriate when disturbances are identified though it is not yet known the degree to which these interventions will affect the pain experience and resultant disability. Future studies should focus on evaluation of specific sleep interventions on patient outcomes.

Findings and Methodological Shortcomings of Investigations Concerning the Relationship Between Sleep Duration and Blood Pressure: A Comprehensive Narrative Review

Cardiology and sleep societies recommend 7-9 h sleep/night for adults (7-8 h for seniors) and more for youngsters; nonetheless, short sleep duration (SSD) of <7 h/night is epidemic. We searched PubMed for representative investigations, including those cited by meta-analyses, that reported association between SSD and long sleep duration (LSD) of >9 h/night and blood pressure (BP) levels to assess shortcomings of their methods. Studies indicate both SSD and LSD negatively impact BP despite major deficiencies, such as (i) reliance mainly on cross-sectional rather than longitudinal protocols, (ii) inclusion of participants diagnosed with hypertension (HTN) and/or taking antihypertension medications, (iii) assessment of BP and diagnosis of HTN performed by single wake-time office measurement rather than multiple measurements performed by 24 h ambulatory BP monitoring (ABPM), and (iv) determination of SD by subjective recall, single-night polysomnography, or diary recordings rather than objective wrist actigraphy of sufficient duration. The limited number of ABPM-based studies, despite evidencing major shortcomings, particularly (i) assessment for 24 h rather than preferred ≥48 h and (ii) inclusion of subjects diagnosed with HTN and/or taking antihypertension medications, also report association between abnormal SD and elevated 24 h 'daytime'/wake-time diastolic and systolic (SBP) means plus 'nighttime'/sleep-time SBP mean and dipping-the latter two indices, in combination, the strongest predictors of major adverse cardiovascular events.

Melatonin secretion across puberty: A systematic review and meta-analysis

BACKGROUND

Melatonin levels decrease with aging and substantially during puberty. Studies have presented distinct melatonin levels in patients with disorders related to their pubertal development compared to healthy controls. The discrepancy suggests that a decrease in melatonin concentrations seen during adolescence might be related to the physical, hormonal, and/or neuronal alterations that occur during the pubertal period. The aim of this review was to analyze the literature reporting melatonin levels in healthy children and adolescents during puberty, and to look for a potential relationship.

METHODS

The Medline and Embase databases were searched on November 28th 2024, including all articles published from 1974 to 2024. Moreover, in the studies eligible for full-text review, a "snowball" search based by backwards referencing was carried out to identify additional studies. This means going through the references of the eligible studies, to find potential other articles relevant for our review and met our inclusion criteria. Lastly, a meta-analysis on serum melatonin concentrations with increasing age and Tanner status was performed.

RESULTS

21 studies were included. 12 studies found a decrease, 5 found no difference and 3 reported an increase in melatonin levels during pubertal advancement. One study could not report secretory alterations but was eligible for inclusion in the meta-analysis. This analysis revealed that Tanner stages were significantly associated with decreasing average as well as peak concentrations of melatonin.

CONCLUSION

The simultaneous occurrence of pubertal progression and chronological aging complicates potential reasons to the decrease observed. However, possible explanations could be related to sex hormones, physical properties of puberty or light exposure. To justify these explanations research in controlled conditions along with biochemical and clinical assessment of pubertal status is needed.

Prospective associations between heterogeneous sleep profiles and depressive symptoms in adolescents: The mediating role of coping styles

INTRODUCTION

Extant literature has linked sleep disturbance to depressive symptoms. However, the coexistence of naturally occurring sleep profiles among adolescents and the prospective associations between sleep profiles and depressive symptoms remain poorly understood. This study aims to uncover sleep patterns in Chinese adolescents based on a comprehensive set of sleep features (e.g., latency, daytime dysfunction, etc.) derived from the Pittsburg Sleep Quality Index (PSQI) and investigate the relationship between these profiles and subsequent depressive symptoms mediated by positive and negative coping styles.

METHODS

Five thousand five hundred five adolescents from Shandong province, China, enrolled (Mage = 16.83 years; 49.9% girls) in a two-wave longitudinal study (T1 in August 2023; T2 in February 2024). Latent class analysis (LCA) was conducted to identify adolescent sleep patterns. Mediation and sensitivity analyses were used to examine prospective associations between sleep patterns, coping styles, and depressive symptoms.

RESULTS

Four qualitatively distinct sleep profiles emerged: Healthy Sleepers (18.9%), Latency but Functioning Sleepers (13.6%), Efficient but Dysfunctional Sleepers (57.5%), and Medicated Maladaptive Sleepers (10.0%). Using the Healthy Sleepers as a reference group, Latency but Functional Sleepers, Efficient but Dysfunctional Sleepers, and Medicated Maladaptive Sleepers all predicted subsequent depressive symptoms through positive coping styles rather than negative coping styles. The relative indirect effects were 0.19, 0.19, and 0.32, respectively.

CONCLUSIONS

The study underscored that adolescents exhibit distinct sleep patterns, and specific sleep profiles may be prospectively associated with depressive symptoms mediated by positive coping styles.

Assessment of sleepiness role in working memory and whole-body reaction time

BACKGROUND

Sleep provides physical and mental strength, and natural sleep is essential for cell growth, strengthening, stabilizing, and accelerating the improvement of memory function.

OBJECTIVE

The current investigation aimed to explore working memory influenced by sleepiness and related to whole-body reaction time, in order to identify some facets of the dynamics of this memory. To the best of our knowledge, this triple has not yet been explored in the literature.

METHODS

This study cross-sectional, descriptive-analytical was performed on a sample total of 45 volunteer undergraduate academic students were recruited by convenience sampling, including 35 females and 10 males with a mean age of 21.08 ± 1.10 years of old. Data were collected via a demographic checklist, Epworth Sleepiness Scale (ESS) questionnaire, Digital Maze test (for working memory), and visual/auditory whole-body reaction time measurement.

RESULTS

The working memory of each subject was divided into three types:1) thoughtful and precise, 2) Cautious and Conservative, and 3) messy and inaccurate. The triple of working memory, reaction time, and sleep versus sleepiness were all significantly related (P = 0.017-0.05).

CONCLUSION

The authors concluded that there might be some established infrastructure for adult working memory, while there might be a floating operator of working memory as well; influenced by various parameters, this study was influenced by sleep adequacy and physical readiness.

Risk and protective factors associated with adolescent depression in Singapore: a systematic review

INTRODUCTION

Adolescent depression is prevalent, and teen suicide rates are on the rise locally. A systemic review to understand associated risk and protective factors is important to strengthen measures for the prevention and early detection of adolescent depression and suicide in Singapore. This systematic review aims to identify the factors associated with adolescent depression in Singapore.

METHODS

A systematic search on the following databases was performed on 21 May 2020: PubMed, EMBASE and PsycINFO. Full texts were reviewed for eligibility, and the included studies were appraised for quality using the Newcastle Ottawa Scale. Narrative synthesis of the finalised articles was performed through thematic analysis.

RESULTS

In total, eight studies were included in this review. The four factors associated with adolescent depression identified were: (1) sociodemographic factors (gender, ethnicity); (2) psychological factors, including childhood maltreatment exposure and psychological constructs (hope, optimism); (3) coexisting chronic medical conditions (asthma); and (4) lifestyle factors (sleep inadequacy, excessive internet use and pathological gaming).

CONCLUSION

The identified factors were largely similar to those reported in the global literature, except for sleep inadequacy along with conspicuously absent factors such as academic stress and strict parenting, which should prompt further research in these areas. Further research should focus on current and prospective interventions to improve mental health literacy, targeting sleep duration, internet use and gaming, and mitigating the risk of depression in patients with chronic disease in the primary care and community setting.

The association between insomnia and suicide attempts among Chinese adolescents: a prospective cohort study

OBJECTIVE

This study aimed to investigate a range of insomnia-related factors, including difficulty with sleep induction, nocturnal awakenings, early awakenings, total sleep time, overall sleep quality, well-being, functioning, and daytime drowsiness, to determine which variables were significantly associated with subsequent adolescent suicide attempts.

METHOD

A total of 782 students aged 11-16 years old from one middle school in Changsha, China completed the survey at baseline and 6 months follow-up with a prospective cohort design. The binary logistic regression models were used to analyze the associations between insomnia variables and suicide attempts during the 6 months follow-up.

RESULTS

The new incidence rate of suicide attempts was 4.60% (36/782) at 6-month follow-up. Insomnia was a significant predictor of incident suicide attempts (OR = 6.00; 95%CI, 2.47-14.60). After adjusting for age, gender, nationality, stress, anxiety and depression, insomnia was found to predict suicide attempts only among female (OR = 4.28; 95%CI, 1.41-12.98) and only nocturnal sleep disruption was significantly associated with an increased risk of suicide attempts (OR = 2.74; 95%CI, 1.32-5.71).

CONCLUSIONS

Nocturnal sleep disruption are independently associated with increased risk of suicide attempts. Intervention for nocturnal sleep disruption may be important for early identification as well as prevention of adolescent suicide, especially among adolescent girls.

Sleep restriction and age effects on distinct aspects of cognition in adolescents

Insufficient sleep negatively impacts scholastic performance in children and adolescents. Here we use a dose-response time in bed (TIB) restriction study to evaluate associations between sleep loss and multiple aspects of cognition. We evaluated changes in cognitive measures across ages 10 to 23 years and determined whether the effects of sleep loss changed across this age range. A younger cohort (n = 77, age range 9.9 to 16.2 years) was studied annually for 3 years. An older cohort study (n = 82, age range 15 to 22.8 years) was interrupted by the COVID pandemic with 25 participants completing multiple years. Annually participants completed each of three TIB conditions: four consecutive nights with 7, 8.5, or 10 hours in bed. A day of cognitive testing followed the fourth night. Restricting TIB to 7 hours was associated with impaired top-down attentional control and cognitive flexibility, but performance did not differ between 8.5 and 10 hours of TIB conditions. Psychomotor vigilance test performance decreased as TIB was restricted from 10 to 8.5 hours and decreased further with restriction to 7 hours. Sternberg test measures of working memory were not significantly affected by TIB restriction. The effects of sleep loss on these cognitive measures did not change significantly with age, but age-related improvement in many of the measures may compensate for some sleep loss effects. The findings here do not indicate an adolescent decrease in sleep need; however, the minimal duration of sleep needed for optimal performance appears to differ depending on the cognitive measure.

Associations between sleep duration, insomnia, depression, anxiety and registry-based school grades: A longitudinal study among high-school students

This study explored the prospective associations between sleep patterns, mental health and registry-based school grades among older adolescents. In the spring of 2019, 1st year high-school students in Western Norway were invited to a survey assessing habitual sleep duration, insomnia, depression and anxiety. Sleep patterns, depression and anxiety were assessed using the Munich ChronoType Questionnaire, the Bergen Insomnia Scale, the Patient Health Questionnaire-9, and the Generalized Anxiety Disorder-7. Students consenting to data linkage with the county school authorities were re-invited 2 years later. Registry-based grade point averages for each of the included school years were accessed through the school authorities. The final longitudinal sample included 1092 students (65.1% girls; initial mean age 16.4 years). Data were analysed using linear mixed models. Longer school night sleep duration and less severe symptoms of insomnia, depression and anxiety were all associated with higher grade point averages at baseline in crude analyses. Shorter school night sleep duration, as well as more severe symptoms of insomnia and depression at baseline, all predicted better grade point averages at 2-year follow-up when controlled for baseline grade point averages. By contrast, anxiety symptomatology at baseline was unrelated to changes in grade point averages over time. The longitudinal associations between school night sleep duration and insomnia symptoms on grade point averages were significant also when adjusted for sex and baseline symptoms of depression and anxiety. These findings indicate that shorter school night sleep duration and more severe insomnia symptoms predict lower grade point averages development over time, irrespective of co-existing symptoms of depression and anxiety.

The impact of sleep restriction on cerebrovascular reactivity and cognitive outcomes in healthy adolescents: A pilot crossover trial

BACKGROUND

The underlying mechanism for the association between sleep restriction (SR) and unfavorable cognitive outcomes in children and adolescents remains unclear. This study aimed to understand the effect of 5-night experimental SR on magnetic resonance imaging (MRI) measurements of cerebrovascular reactivity (CVR) and cognitive function in adolescents.

METHODS

This randomized crossover study compared two sleep conditions, SR and Control Sleep (CS) in a home setting. Healthy adolescents aged 15-18 years were recruited. The protocol began with two nights of baseline sleep to record participants' habitual sleep duration, followed by the two sleep conditions in the randomly allocated sequence, either SR (6 h in bed for 5 nights) followed by CS (9 h in bed for 5 nights), or the reverse sequence. Their sleep-wake pattern was monitored by an accelerometer and a sleep diary throughout the study period. Cerebral hemodynamics were assessed by hypercapnic challenge blood oxygen level-dependent (BOLD) MRI of CVR. Cognitive function was evaluated by NIH Toolbox Cognitive Battery on the day immediately after each sleep condition.

RESULTS

A total of 27 participants (8 males; mean age: 16.8 ± 0.7 years, range 15-18 years) were included in the study. The average sleep duration was significantly reduced in the SR condition compared to the CS condition (320 ± 34 min vs. 426 ± 45 min, p < 0.001). The CVR in the temporal occipital fusiform cortex [adjusted β(95 % CI) = -0.091(-0.010 to -0.172), p = 0.032] and occipital lobe [adjusted β(95 % CI) = -0.087 (-0.002 to -0.172), p = 0.045] was significantly lower following the SR condition when compared to the CS condition. Participants also had lower performance scores in the inhibitory control [adjusted β(95 % CI) = -6.0(-0.9 to -11.0), p = 0.019] and cognitive flexibility [adjusted β(95 % CI) = -6.6 (-1.7 to -11.6), p = 0.008] domains after the SR condition when compared to the CS condition.

CONCLUSIONS

Short-term SR is associated with poorer cognitive function possibly through reduced cerebral vasodilatory capacity in specific cognitive regions.

Effects of total sleep deprivation on functional connectivity of the anterior cingulate cortex: Insights from resting-state fMRI in healthy adult males

Inadequate sleep significantly impacts an individual's health by compromising inhibitory control and self-regulation abilities. This study employed resting-state functional magnetic resonance imaging (fMRI) to assess the functional connectivity between the anterior cingulate cortex (ACC) and the whole brain in 16 healthy adult males after 36 h of total sleep deprivation. Additionally, this study investigated alterations in individuals' inhibitory control functions and physiological mechanisms following sleep deprivation. The results showed a significant increase in functional connectivity between the ACC, the left angular gyrus, and the right hippocampus following 36 h of continuous sleep deprivation. Conversely, functional connectivity was notably decreased between the ACC and the right insular cortex, right paracingulate gyrus, and bilateral putamen. Furthermore, changes in ACC functional connectivity were significantly correlated with alterations in behavioral performance in the go/no-go task after sleep deprivation. This study contributes to understanding brain network mechanisms in the anterior cingulate gyrus after sleep deprivation. It clarifies the relationship between functional connectivity changes in the anterior cingulate gyrus and inhibitory control post-sleep deprivation.

Characteristics and Transition of Sleep-Wake Rhythm in Nursery School Children: The Importance of Nocturnal Sleep

In this study, we investigated the sleep-wake rhythm of nursery school children with the aim of supporting their health and mental/physical development. We analyzed 4881 children from infancy to 6 years of age, using 2 week sleep tables recorded by their guardians. The tables contained night bedtimes, wake times, nighttime/daytime sleep duration, and the differences in these between weekdays and weekends. The total sleep decrement of children with increasing age is attributed to a decrease in daytime sleep, while nighttime sleep duration remains almost unchanged at about 10 h, which is, therefore, referred to as the nighttime basic sleep duration (NBSD). Although bedtime stabilizes at around 9:30 p.m. by the age of 2, wake-up times tend to be before 7 a.m., which results in sleep insufficiency during weekdays. This lack of sleep is compensated for by long naps on weekdays and by catching up on sleep on weekend mornings, which may contribute to future social jet lag. Guardians are encouraged to know their children's exact NBSD and set an appropriate bedtime to be maintained on weekdays. This helps to prevent sleep debt and fosters a consistent daily rhythm of waking up at the same time both on weekdays and weekends. These conditions are believed to support mental/physical development and school and social adaptation.

Illuminating Hypomania in Early Adolescence: Associations Between Dark-Side and Bright-Side Hypomania, Insomnia, and Health-Related Quality of Life

Background: Adolescence is a period of significant psychological, physical, and social changes. During this time, adolescents face increasing responsibilities, such as making educational and career decisions, managing peer relationships, and becoming more independent from their families. These changes are often accompanied by mood fluctuations and altered sleep patterns. This study aimed to explore the relationships between bright- and dark-side hypomania, insomnia, and various dimensions of health-related quality of life (HRQOL), such as self-esteem, family and peer relationships, social acceptance, and autonomy. Methods: A total of 1475 participants in mid-adolescence (mean age: 13.4 years; range: 11-16 years; 48.8% males) completed a series of self-reported questionnaires covering sociodemographic information, hypomania, including dark and bright-side hypomania, insomnia, and HRQOL. Results: Compared to participants with no or dark-side hypomania, participants with bright-side hypomania reported better HRQOL. Bright-side hypomania was significantly associated with favorable relationships with parents and home, peer relationships, and the school environment and with less insomnia. In contrast, dark-side hypomania showed significant associations with lower scores for self-esteem, moods and emotional states, peer relationships, social acceptance, the school environment, and more insomnia. Conclusions: Among a larger sample of adolescents, bright- and dark-side hypomania were associated with a broad, though specific variety of aspects of HRQOL and insomnia. Given that standardized programs are available to improve insomnia and resilience as a proxy of psychological well-being, such interventions may have the potential to improve adolescents' psychological well-being and sleep quality concomitantly.

Effects of Sleep Quality, Acute Sleep Deprivation, and Napping on Facial Emotion Recognition Accuracy and Speed

Objective

To investigate the effects of sleep quality, sleep deprivation, and napping on facial emotion recognition (FER) accuracy and speed.

Methods

This research included a cross-sectional study (102 qualified participants) and a randomized controlled study (26 in the napping group and 24 in the control group). The stimuli for the FER task were obtained from the Chinese Facial Affective Picture System (CFAPS). Four facial expressions (fearful, disgusted, sad, and angry) were used. The Pittsburgh Sleep Quality Index (PSQI), Self-Rating Anxiety Scale, and Self-Rating Depression Scale were used to measure participants' sleep quality and psychological conditions. In Study 1, FER ability was compared between good and poor sleepers. In Study 2, all participants were sleep-deprived for one night, and completed the FER task before and after sleep deprivation. After different interventions (ie, napping for one hour, or walking around for ten minutes), the participants completed the third FER task.

Results

Study 1: Poor sleepers were able to recognize sad expressions more accurately compared with good sleepers. Study 2: 30-h sleep deprivation had no significant effect on the accuracy (ACC). Napping after sleep deprivation improved the FER ACC of upper-face expressions and marginally significantly improved the FER ACC of disgusted expressions.

Conclusion

Better sleep quality was linked to lower FER accuracy, particularly in recognizing sad expressions, while no significant differences in recognition speed were observed. Additionally, 30 hours of sleep deprivation did not affect FER accuracy, but napping after sleep deprivation improved accuracy for upper-face and marginally for disgusted expressions.

Continuous Theta Burst Stimulation Inhibits Oxidative Stress-Induced Inflammation and Autophagy in Hippocampal Neurons by Activating Glutathione Synthesis Pathway, Improving Cognitive Impairment in Sleep-Deprived Mice

Sleep deprivation (SD) has been reported to have a negative impact on cognitive function. Continuous theta burst stimulation (cTBS) shows certain effects in improving sleep and neurological diseases, and its molecular or cellular role in SD-induced cognition impairment still need further exploration. In this study, C57BL/6 mice were subjected to 48 h of SD and cTBS treatment, and cTBS treatment significantly improved SD-triggered impairment of spatial learning and memory abilities in mice. Additionally, cTBS reduced malondialdehyde levels, increased superoxide dismutase activities, and inhibited the production of inflammatory cytokines, alleviating oxidative stress and inflammation levels in hippocampal tissues of SD model mice. cTBS decreased LC3II/LC3I ratio, Beclin1 protein levels, and LC3B puncta intensity, and elevated p62 protein levels to suppress excessive autophagy in hippocampal tissues of SD-stimulated mice. Then, we proved that inhibiting oxidative stress alleviated inflammation, autophagy, and death of hippocampal neuron cells through an in vitro cellular model for oxidative stress, and cTBS treatment promoted the production of glutathione (GSH), the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and the mRNA expression of GSH synthesis-related genes to enhance antioxidant capacity in hippocampal tissues of SD mice. An Nrf2 inhibitor ML385 or a GSH synthesis inhibitor BSO reversed the alleviating effects of cTBS treatment on oxidative stress-associated damage of hippocampal tissues and cognitive impairment in SD model mice. Altogether, our study demonstrated that cTBS mitigates oxidative stress-associated inflammation and autophagy through activating the Nrf2-mediated GSH synthesis pathway, improving cognitive impairment in SD mice.

Can weekend catch-up sleep decrease the risk of cognitive dysfunction in older adults?

PURPOSE

This study investigated whether weekend catch-up sleep was related to a decreased risk of cognitive dysfunction in older Taiwanese adults by using self-reported diaries and objective accelerometer measurements.

METHODS

This cross-sectional study enrolled participants who were aged ≥ 65 years and had the capability to walk independently from a medical center in Taipei City, Taiwan, between September 2020 and December 2022. Self-reported sleep diaries and tri-axial accelerometers were used to record and measure sleep-related data for 7 consecutive nights. Weekend catch-up sleep was defined as the mean of weekend sleep time minus the mean of weekdays sleep time. Mini-Mental State Examination (MMSE) was evaluated the risk of cognitive dysfunction. The association between weekend catch-up sleep and the MMSE score was examined using a binary logistic regression model.

RESULTS

A total of 215 older adults (53.0% female; 80.5 ± 7.1 years old; 11.6% at risk of cognitive dysfunction) were included. In the adjusted model (adjusted for sex, education level, moderate-to-vigorous physical activity and total accelerometer wear time), both the self-reported sleep diaries (odds ratio [OR] = 0.26, 95% confidence interval [CI] = 0.09-0.69, P = 0.007) and the accelerometer data (OR = 0.27, 95% CI = 0.10-0.70, P = 0.007) indicated that weekend catch-up sleep could decrease the risk of cognitive dysfunction by 73-74%.

CONCLUSION

The study findings suggest that there is an association between weekend catch-up sleep and lower risk for cognitive decline. The causal relationship between weekend catch-up sleep and cognitive function in older adults should be further investigated in a study with longitudinal design.

A randomized controlled trial modifying insomnia-consistent interpretation bias in students

This study aimed to determine the causal role of insomnia-consistent interpretation bias within the cognitive model of insomnia, by modifying this bias in students experiencing subclinical levels of insomnia and assessing subsequent effects on sleep parameters. A sample of 128 students underwent randomization to receive either a single session of online Cognitive Bias Modification-Interpretation (CBM-I) or a sham training. Participants then tracked their pre-sleep worry and sleep parameters for seven consecutive days. Interpretation bias was assessed using an encoding-recognition task specifically designed for insomnia-related interpretation bias. The CBM-I manipulation utilized ambiguous scenarios to redirect participants away from making insomnia-related interpretations. Results revealed that CBM-I effectively decreased insomnia-consistent interpretation bias compared to the sham treatment, with interpretation bias being absent post-training in the CBM-I group. This reduction did not lead to improvements in pre-sleep worry or any sleep parameters. This study has been the first to investigate the causal role of interpretation bias on symptoms of insomnia. Although results indicated this bias to be modifiable, its causality within the cognitive model proves to be more complicated. Future research focusing on optimization of cognitive bias modifications could shed more light on the effects of biased cognitions on insomnia symptoms.

Nocturnal hypoglycemia is associated with next day cognitive performance in adults with type 1 diabetes: Pilot data from the GluCog study

OBJECTIVE

 Individuals with type 1 diabetes (T1D) have increased risk for cognitive dysfunction and high rates of sleep disturbance. Despite associations between glycemia and cognitive performance using cross-sectional and experimental methods few studies have evaluated this relationship in a naturalistic setting, or the impact of nocturnal versus daytime hypoglycemia. Ecological Momentary Assessment (EMA) may provide insight into the dynamic associations between cognition, affective, and physiological states. The current study couples EMA data with continuous glucose monitoring (CGM) to examine the within-person impact of nocturnal glycemia on next day cognitive performance in adults with T1D. Due to high rates of sleep disturbance and emotional distress in people with T1D, the potential impacts of sleep characteristics and negative affect were also evaluated.

METHODS

 This pilot study utilized EMA in 18 adults with T1D to examine the impact of glycemic excursions, measured using CGM, on cognitive performance, measured via mobile cognitive assessment using the TestMyBrain platform. Multilevel modeling was used to test the within-person effects of nocturnal hypoglycemia and hyperglycemia on next day cognition.

RESULTS

 Results indicated that increases in nocturnal hypoglycemia were associated with slower next day processing speed. This association was not significantly attenuated by negative affect, sleepiness, or sleep quality.

CONCLUSIONS

 These results, while preliminary due to small sample size, showcase the power of intensive longitudinal designs using ambulatory cognitive assessment to uncover novel determinants of cognitive fluctuation in real world settings, an approach that may be utilized in other populations. Findings suggest reducing nocturnal hypoglycemia may improve cognition in adults with T1D.

The inter-related effects of alcohol use severity and sleep deficiency on semantic processing in young adults

BACKGROUND

Both alcohol misuse and sleep deficiency are associated with deficits in semantic processing. However, alcohol misuse and sleep deficiency are frequently comorbid and their inter-related effects on semantic processing as well as the underlying neural mechanisms remain to be investigated.

METHODS

We curated the Human Connectome Project data of 973 young adults (508 women) to examine the neural correlates of semantic processing in link with the severity of alcohol use and sleep deficiency. The latter were each evaluated using the first principal component (PC1) of principal component analysis of all drinking metrics and the Pittsburgh Sleep Quality Index (PSQI). We employed path modeling to elucidate the interplay among clinical, behavioral, and neural variables.

RESULTS

Among women, we observed a significant negative correlation between the left precentral gyrus (PCG) and PSQI scores. Mediation analysis revealed that the left PCG activity fully mediated the relationship between PSQI scores and word comprehension in language tasks. In women alone also, the right middle frontal gyrus (MFG) exhibited a significant negative correlation with PC1. The best path model illustrated the associations among PC1, PSQI scores, PCG activity, and MFG activation during semantic processing in women.

CONCLUSIONS

Alcohol misuse may lead to reduced MFG activation while sleep deficiency hinder semantic processing by suppressing PCG activity in women. The pathway model underscores the influence of sleep quality and alcohol consumption severity on semantic processing in women, suggesting that sex differences in these effects need to be further investigated.

The dynamic responses of mood and sleep physiology to chronic sleep restriction and subsequent recovery sleep

Healthy sleep of sufficient duration preserves mood and disturbed sleep is a risk factor for a range of psychiatric disorders. As adults commonly experience chronic sleep restriction (SR), an enhanced understanding of the dynamic relationship between sleep and mood is needed, including whether susceptibility to SR-induced mood disturbance differs between sexes. To address these gaps, data from N = 221 healthy adults who completed one of the two multi-day laboratory studies with identical 9-day SR protocols were analyzed. Participants randomized to the SR (n = 205) condition underwent 5 nights of SR to 4 hours of time-in-bed and were then randomized to one of the seven sleep doses that ranged from 0 to 12 hours in 2 hours increments; participants randomized to the control (n = 16) condition received 10 hours time-in-bed on all study nights. The Profile of Mood States (POMS) was used to assess mood every 2 hours during wakefulness and markers of sleep homeostasis (EEG slow-wave activity (SWA)) were derived via polysomnography. Mood progressively deteriorated across SR with marked disturbances in somatic mood components. Altered sleep physiology contributed to mood disturbance whereby increased EEG SWA was associated with increased POMS Total Mood Disturbance scores, a finding specific to males. The mood was restored in a dose-response fashion where improvements were greater with longer sleep doses. These findings suggest that when lifestyle and environmental factors are inhibited in the laboratory, the affective consequences of chronic sleep loss are primarily somatic mood disturbances. Altered sleep homeostasis may contribute to mood disturbance, yet sleep-dependent mechanisms may be sex-specific.

Bidirectional associations between the duration and timing of nocturnal sleep and daytime naps in adolescents differ from weekdays to weekends

STUDY OBJECTIVES

Previous studies examining bidirectional relationships between nocturnal sleep and napping have focused on sleep duration, leaving a gap in our understanding of how sleep timing contributes. Here, we assessed the duration and timing for night sleep and daytime naps, to evaluate how the previous night's sleep influences the next day's napping, and how napping influences same-night nocturnal sleep.

METHODS

We analyzed sleep diary and actigraphy data from 153 teens (males = 43.8%, mean age = 16.6 years). Participants who never napped were excluded. Nocturnal sleep-nap relationships were investigated using logistic and linear regression models separately for weekdays and weekends.

RESULTS

Participants napped an average of 2.3 times a week. 167 school day naps and 107 weekends were recorded. Naps were on average 82.12 ± 53.34 minutes and the average nap onset was 14:58 ± 3.78 hours. Their duration, start and end times did not significantly differ between weekdays and weekends. Nocturnal sleep duration did not predict next-day nap occurrence or duration. However, on school days, earlier wake times significantly increased the likelihood of napping that day, and advanced nap timing. On weekends, later bedtimes and wake times delayed nap timing. On school days, napping longer than one's average shortened nocturnal sleep whereas on weekends, waking from a nap later than one's average delayed bedtimes.

CONCLUSIONS

Early wake times increase the likelihood of napping and advance the time of a nap that day. Naps may be detrimental to the same night's sleep only if they are long and occur late, as these can delay bedtimes and shorten nocturnal sleep duration, especially on school days.

CLINICAL TRIALS

The Cognitive and Metabolic Effects of Sleep Restriction in Adolescents (NFS4), https://clinicaltrials.gov/study/NCT03333512, ID: NCT03333512. Investigating Preferred Nap Schedules for Adolescents (NFS5), https://clinicaltrials.gov/study/NCT04044885, ID: NCT04044885.

Neuroelectrophysiological alteration associated with cognitive flexibility after 24 h sleep deprivation in adolescents

The cognitive neural mechanisms by which sleep deprivation affects cognitive flexibility are poorly understood. Therefore, the study investigated the neuroelectrophysiological basis of the effect of 24 h sleep deprivation on cognitive flexibility in adolescents. 72 participants (36 females, mean age ± SD=20.46 ± 2.385 years old) participated in the study and were randomly assigned to the sleep deprivation group and control group. They were instructed to complete a task switch paradigm, during which participants' behavioral and electroencephalographic data were recorded. Behaviorally, there were significant between-group differences in accuracy. The results of event-related potential showed that the P2, N2 and P3 components had significant group effects or interaction effects. At the time-frequency level, there were statistically significant differences between the delta and theta bands. These results suggested that 24 h sleep deprivation affected problem-solving effectiveness rather than efficiency, mainly because it systematically impaired cognitive processing associated with cognitive flexibility.

NLRP3-mediated autophagy dysfunction links gut microbiota dysbiosis to tau pathology in chronic sleep deprivation

Emerging evidence indicates that sleep deprivation (SD) can lead to Alzheimer's disease (AD)-related pathological changes and cognitive decline. However, the underlying mechanisms remain obscure. In the present study, we identified the existence of a microbiota-gut-brain axis in cognitive deficits resulting from chronic SD and revealed a potential pathway by which gut microbiota affects cognitive functioning in chronic SD. Our findings demonstrated that chronic SD in mice not only led to cognitive decline but also induced gut microbiota dysbiosis, elevated NLRP3 inflammasome expression, GSK-3β activation, autophagy dysfunction, and tau hyperphosphorylation in the hippocampus. Colonization with the "SD microbiota" replicated the pathological and behavioral abnormalities observed in chronic sleep-deprived mice. Remarkably, both the deletion of NLRP3 in NLRP3 -/- mice and specific knockdown of NLRP3 in the hippocampus restored autophagic flux, suppressed tau hyperphosphorylation, and ameliorated cognitive deficits induced by chronic SD, while GSK-3β activity was not regulated by the NLRP3 inflammasome in chronic SD. Notably, deletion of NLRP3 reversed NLRP3 inflammasome activation, autophagy deficits, and tau hyperphosphorylation induced by GSK-3β activation in primary hippocampal neurons, suggesting that GSK-3β, as a regulator of NLRP3-mediated autophagy dysfunction, plays a significant role in promoting tau hyperphosphorylation. Thus, gut microbiota dysbiosis was identified as a contributor to chronic SD-induced tau pathology via NLRP3-mediated autophagy dysfunction, ultimately leading to cognitive deficits. Overall, these findings highlight GSK-3β as a regulator of NLRP3-mediated autophagy dysfunction, playing a critical role in promoting tau hyperphosphorylation.

Social Media Use and Sleep Quality Among Secondary School Students in Aseer Region: A Cross-Sectional Study

Background

Use of different social media platforms has increased radically over the past decade, emerging as an important part of adolescents and young people's everyday life. This might exert potential adverse effects on sleep quality and daytime performance of young adults.

Aim of Study

To assess the relation between use of social media platforms and sleep quality among public secondary school students.

Methods

A cross-sectional study was conducted on 961 students in Aseer region, Saudi Arabia. Students were asked to fill in a structured interview questionnaire covering personal data, pattern of social media use, sleep quality using The Pittsburgh Sleep Quality Index (PSQI) and their mental health status using the depression, anxiety and stress scale (DASS-21).

Results

Students' ages ranged from 15 to 20 years with a mean age of 16.7 ± 2.1 years old. A total of 570 (59.3%) students were females. Tiktok (80%), Snapchat (77.9%), Instagram (63.8%) and YouTube (58.8%) were the most reported platforms used. Regarding their sleep quality, 34.7% of students were poor sleepers. TikTok use (OR 1.33, 95% CI 1.01-1.77), hours spent on social media (OR 1.26, 95% CI 1.16-1.37) and having moderate to severe depressive symptoms (OR 1.69, 95% CI 1.19-2.40) were significant independent predictors of poor sleep among the studied sample.

Conclusion

The present study emphasized the association between prolonged use of social media and poor sleep quality among Saudi adolescents. Awareness and behavioral change strategies and activities concerning the drawbacks of poor sleep and proper use of social media are urgently called for to control mental and physical health consequences of poor sleep and social media addiction.

What the Fika? Implementation of Swedish Coffee Breaks During Emergency Medicine Conference

Introduction

In this study we aimed to investigate the effects of incorporating Swedish-style fika (coffee) breaks into the didactic schedule of emergency medicine residents on their sleepiness levels during didactic sessions. Fika is a Swedish tradition that involves a deliberate decision to take a break during the workday and usually involves pastries and coffee. We used the Karolinska Sleepiness Scale to assess changes in sleepiness levels before and after the implementation of fika breaks.

Methods

The study design involved a randomized crossover trial approach, with data collected from emergency medicine residents over a specific period. This approach was done to minimize confounding and to be statistically efficient.

Results

Results revealed the average sleepiness scale was 4.6 and 5.5 on fika and control days, respectively (P = 0.004).

Conclusion

Integration of fika breaks positively influenced sleepiness levels, thus potentially enhancing the educational experience during residency didactics.

Psychological endurance: how grit, resilience, and related factors contribute to sustained effort despite adversity

Many concepts describe how individuals sustain effort despite challenging circumstances. For example, scholars and practitioners may incorporate discussions of grit, hardiness, self-control, and resilience into their ideas of performance under adversity. Although there are nuanced points underlying each construct capable of generating empirically sound propositions, the shared attributes make them difficult to differentiate. As a result, substantial confusion arises when debating how these related factors concomitantly contribute to success, especially when practitioners attempt to communicate these ideas in applied settings. The model proposed here-psychological endurance-is a unified theory to explore how multiple concepts contribute to sustained goal-directed behaviors and individual success. Central to this model is the metaphor of a psychological battery, which potentiates and sustains optimal performance despite adversity. Grit and hardiness are associated with the maximum charge of the psychological battery, or how long an individual could sustain effort. Self-control modulates energy management that augments effort required to sustain endurance, whereas resilience represents the ability to recharge. These factors are constrained by both psychological and physiological stressors in the environment that drain the psychology battery. Taken together, these ideas form a novel framework to discuss related psychological concepts, and ideally, optimize intervention to enhance psychological endurance.

How do adolescents experience a newly developed Online Single Session Sleep Intervention? A Think-Aloud Study

BACKGROUND

Sleep problems are common in adolescents and have detrimental impacts on physical and mental health and daily functioning. Evidence-based treatment like cognitive behaviour therapy for insomnia (CBT-I) is often hard to access, and adolescents may not engage in and adhere to longer, clinician-delivered interventions. Brief, self-guided, and accessible sleep interventions are needed.

OBJECTIVE

To explore the user experience of a prototype online self-help single session sleep intervention developed for adolescents.

METHODS

Eleven participants aged 17-19 years (8 females, 3 males) took part in online retrospective think-aloud interviews. Participants first completed the prototype intervention independently and were then shown the intervention page by page and asked to verbalise their thoughts and experiences. Transcripts were analyzed thematically.

RESULTS

Participants found the intervention helpful. Four themes were generated - 'Educative: Learning, but more fun', 'Effortless: Quicker and Easier', 'Personalization: Power of Choice', and 'Positivity: Just Good Vibes'. The theme 'Educative: Learning, but more fun' encompassed two sub-themes 'Opportunity to Learn' and 'Aesthetics and Learning'. These themes reflected participants' views that the intervention was educative, personalised, solution-oriented and easy to use, but could incorporate more graphics and visuals to aid in learning and could be made more effortless and positive through modifications to its design.

CONCLUSIONS

Findings convey the importance of ensuring educative well-designed content, personalization, a positive tone, and ease of use while designing interventions targeting adolescents's sleep and mental health. They also indicate areas for further developing the intervention.

Effect of Sleep Restriction on Adolescent Cognition by Adiposity: A Randomized Crossover Trial

Importance

Pediatric obesity is associated with impaired cognitive function; however, the mechanisms underlying this association demand assessment. Sleep may be a relevant moderator, as poor sleep predicts both increased adiposity and impaired cognitive function.

Objective

To determine the effects of adiposity and sleep on adolescent cognitive function.

Design, Setting, and Participants

This single-blind randomized crossover trial was conducted from September 2020 to October 2022. Parents or caregivers provided demographic information for adolescent participants. Body mass index percentile and bioelectrical impedance analysis assessed adiposity. Adolescents completed 2 actigraphy-confirmed sleep conditions, adequate and restricted, followed by in-person cognitive assessment. No additional follow-up was provided. Data collection for this population-based study took place in a behavioral medicine clinic in Birmingham, Alabama. A total of 323 participants were assessed for eligibility (ages 14-19 years and healthy). Of the 244 eligible adolescents, 157 declined participation. Eighty-seven were randomized and 26 dropped out postenrollment. The final sample included 61 adolescents, 31 with healthy weight and 30 with overweight or obesity. Data were analyzed from April to October 2023.

Interventions

Following a 2-day washout period of adequate sleep, adolescents completed 2 sleep conditions: adequate (mean [SD] duration, 8 hours, 54 minutes [58.0 minutes]) and restricted (mean [SD] duration, 4 hours, 12 minutes [50.7 minutes]).

Main Outcomes and Measures

The National Institutes of Health Cognitive Toolbox assessed global and fluid cognition, cognitive flexibility, working and episodic memory, attention, and processing speed. The Stroop Task assessed inhibition.

Results

The final sample included 61 adolescents (mean [SD] age, 16.3 [1.6] years; 35 [57.4%] female). Restricted sleep predicted poorer global cognition scores (restricted mean [SD], 98.0 [2.8]; adequate mean [SD], 103.2 [2.9]), fluid cognition scores (restricted mean [SD], 94.5 [3.2]; adequate mean [SD], 102.0 [3.6]), and cognitive flexibility scores (restricted mean [SD], 84.8 [3.0]; adequate mean [SD], 92.8 [3.0]) for adolescents with overweight or obesity. No differences emerged for adolescents with healthy weight. Adolescents with overweight or obesity also had poorer attention scores (mean [SD], 80.0 [2.3]) compared to adolescents with healthy weight (mean [SD], 88.4 [SD, 2.3]) following restricted sleep. No differences emerged following adequate sleep. Findings were similar for total body fat percentage (TBF%); however, for adolescents with TBF% above 42, restricted sleep also predicted poorer processing speed, and the association between sleep and attention did not vary based on TBF%.

Conclusions and Relevance

Adolescents with overweight or obesity may be more vulnerable to negative cognitive effects following sleep restriction. Improved sleep hygiene and duration in this group may positively impact their cognitive health.

Trial Registration

ClinicalTrials.gov Identifier: NCT04346433.

The impact of sleep quality on visual working memory varied with the duration of maintenance

Objective

Sleep quality can affect the performance of visual working memory. However, the effect of sleep quality on the maintenance stage, which is the key to maintain the quality and efficiency of visual working memory representation, remains unclear. This study is the first to explore the effect of sleep quality on the maintenance of visual working memory information.

Method

60 healthy college students completed the Pittsburgh Sleep Quality Index (PSQI) and color recall task of visual working memory. A mixed experimental design of sleep quality (high or low) and delay duration (1, 4, or 6 s) was used to assess the effect of sleep quality on the maintenance phase of visual working memory.

Results

The main effects of sleep quality were significant on visual working memory quantity, precision and offset indexes. Among the quantity index, the interaction between sleep quality and delay duration was also significant. This suggests that prolonging the delay time in the maintenance phase leads to difficulty in maintaining attention to the task for those with lower sleep quality, which results in poorer working memory quantitative representations.

Conclusion

Increases in the delay duration of the maintenance phase in visual working memory intensify the impact of sleep quality on task performance. Our study provides evidence to reveal the relationship between sleep quality and visual working memory and offers recommendations for improving sleep quality and cognitive functioning in individuals.

Global, regional, and national health inequalities of Alzheimer's disease and Parkinson's disease in 204 countries, 1990-2019

BACKGROUND

Alzheimer's disease and related dementias (ADRD) and Parkinson's disease (PD), pose growing global health challenges. Socio-demographic and economic development acts paradoxically, complicating the process that determines how governments worldwide designate policies and allocate resources for healthcare.

METHODS

We extracted data on ADRD and PD in 204 countries from the Global Burden of Disease 2019 database. Health disparities were estimated using the slope index of inequality (SII), and concentration index (CIX) based on the socio-demographic index. Estimated annual percentage changes (EAPCs) were employed to evaluate temporal trends.

RESULTS

Globally, the SII increased from 255.4 [95% confidence interval (CI), 215.2 to 295.5)] in 1990 to 559.3 (95% CI, 497.2 to 621.3) in 2019 for ADRD, and grew from 66.0 (95% CI, 54.9 to 77.2) in 1990 to 132.5 (95% CI, 118.1 to 147.0) in 2019 for PD; CIX rose from 33.7 (95% CI, 25.8 to 41.6) in 1990 to 36.9 (95% CI, 27.8 to 46.1) in 2019 for ADRD, and expanded from 22.2 (95% CI, 21.3 to 23.0) in 1990 to 29.0 (95% CI, 27.8 to 30.3) in 2019 for PD. Age-standardized disability-adjusted life years displayed considerable upward trends for ADRD [EAPC = 0.43 (95% CI, 0.27 to 0.59)] and PD [0.34 (95% CI, 0.29 to 0.38)].

CONCLUSIONS

Globally, the burden of ADRD and PD continues to increase with growing health disparities. Variations in health inequalities and the impact of socioeconomic development on disease trends underscored the need for targeted policies and strategies, with heightened awareness, preventive measures, and active management of risk factors.

Presenteeism and sleep duration on workdays and days off

BACKGROUND

Presenteeism refers to being present at work but experiencing reduced productivity due to health problems, and has been known to be related to sleep loss. Workers commonly sleep longer on days off than on workdays, and presenteeism may be reduced with extended sleep on days off.

AIMS

This study aimed to determine the association between sleep duration both on workdays and days off and presenteeism.

METHODS

The participants were 1967 workers who engaged in work for 5 days and rested for 2 days weekly. Sleep duration was classified into less than 6 hours (short; S), 6-8 hours (medium; M), and 9 hours or longer (long; L), for workdays and days off, respectively. Presenteeism was assessed using the World Health Organization Health and Work Performance Questionnaire.

RESULTS

On both workdays and days off, compared to medium sleep duration, short sleep duration was significantly associated with increased odds of presenteeism. The odds of presenteeism were significantly increased for S-S (odds ratio [OR] 2.17, 95% confidence interval [CI]1.40-3.37), S-M (OR 1.59, 95% CI 1.14-2.22), S-L (OR 2.71, 95% CI 1.05-7.00), and M-S (OR 6.82, 95% CI 2.71-17.17) combined sleep duration for workdays and days off, respectively, compared to an M-M (reference).

CONCLUSIONS

Sleep loss on workdays cannot be compensated for with longer sleep on days off. This study suggests that sufficient sleep duration on both workdays and days off is important for reducing presenteeism.

Napping and circadian sleep-wake regulation during healthy aging

STUDY OBJECTIVES

Daytime napping is frequently reported among the older population and has attracted increasing attention due to its association with multiple health conditions. Here, we tested whether napping in the aged is associated with altered circadian regulation of sleep, sleepiness, and vigilance performance.

METHODS

Sixty healthy older individuals (mean age: 69 years, 39 women) were recruited with respect to their napping habits (30 nappers, 30 non-nappers). All participants underwent an in-lab 40-hour multiple nap protocol (10 cycles of 80 minutes of sleep opportunity alternating with 160 minutes of wakefulness), preceded and followed by a baseline and recovery sleep period. Saliva samples for melatonin assessment, sleepiness, and vigilance performance were collected during wakefulness and electrophysiological data were recorded to derive sleep parameters during scheduled sleep opportunities.

RESULTS

The circadian amplitude of melatonin secretion was reduced in nappers, compared to non-nappers. Furthermore, nappers were characterized by higher sleep efficiencies and REM sleep proportion during day- compared to nighttime naps. The nap group also presented altered modulation in sleepiness and vigilance performance at specific circadian phases.

DISCUSSION

Our data indicate that napping is associated with an altered circadian sleep-wake propensity rhythm. They thereby contribute to the understanding of the biological correlates underlying napping and/or sleep-wake cycle fragmentation during healthy aging. Altered circadian sleep-wake promotion can lead to a less distinct allocation of sleep into nighttime and/or a reduced wakefulness drive during the day, thereby potentially triggering the need to sleep at adverse circadian phase.

Sleep deprivation-induced anxiety-like behaviors are associated with alterations in the gut microbiota and metabolites

The present study aimed to characterize the gut microbiota and serum metabolome changes associated with sleep deprivation (SD) as well as to explore the potential benefits of multi-probiotic supplementation in alleviating SD-related mental health disorders. Rats were subjected to 7 days of SD, followed by 14 days of multi-probiotics or saline administration. Open-field tests were conducted at baseline, end of SD (day 7), and after 14 days of saline or multi-probiotic gavage (day 21). Metagenomic sequencing was conducted on fecal samples, and serum metabolites were measured by untargeted liquid chromatography tandem-mass spectrometry. At day 7, anxiety-like behaviors, including significant decreases in total movement distance (P = 0.0002) and staying time in the central zone (P = 0.021), were observed. In addition, increased levels of lipopolysaccharide (LPS; P = 0.028) and decreased levels of uridine (P = 0.018) and tryptophan (P = 0.01) were detected in rats after 7 days of SD. After SD, the richness of the gut bacterial community increased, and the levels of Akkermansia muciniphila, Muribaculum intestinale, and Bacteroides caecimuris decreased. The changes in the host metabolism and gut microbiota composition were strongly associated with the anxiety-like behaviors caused by SD. In addition, multi-probiotic supplementation for 14 days modestly improved the anxiety-like behaviors in SD rats but significantly reduced the serum level of LPS (P = 0.045). In conclusion, SD induces changes in the gut microbiota and serum metabolites, which may contribute to the development of chronic inflammatory responses and affect the gut-brain axis, causing anxiety-like behaviors. Probiotic supplementation significantly reduces serum LPS, which may alleviate the influence of chronic inflammation.

IMPORTANCE

The disturbance in the gut microbiome and serum metabolome induced by SD may be involved in anxiety-like behaviors. Probiotic supplementation decreases serum levels of LPS, but this reduction may be insufficient for alleviating SD-induced anxiety-like behaviors.

Neurobehavioral functions during recurrent periods of sleep restriction: effects of intra-individual variability in sleep duration

STUDY OBJECTIVES

To investigate whether neurobehavioral impairments are exacerbated during successive cycles of sleep restriction and recovery in young adults, and whether a variable short sleep schedule can mitigate these impairments relative to a stable one.

METHODS

Fifty-two healthy young adults (25 males, aged: 21-28) were randomly assigned to the stable short sleep group, the variable short sleep group, or the control group in this laboratory-based study. They underwent two baseline nights of 8-hour time-in-bed (TIB), followed by two cycles of "weekday" sleep opportunity manipulation and "weekend" recovery (8-hour TIB). During each manipulation period, the stable short sleep and the control groups received 6- and 8-hour TIBs each night respectively, while the variable short sleep group received 8-hour, 4-hour, 8-hour, 4-hour, and 6-hour TIBs from the first to the fifth night. Neurobehavioral functions were assessed five times each day.

RESULTS

The stable short sleep group showed faster vigilance deterioration in the second week of sleep restriction as compared to the first. This effect was not observed in the variable short sleep group. Subjective alertness and practice-based improvement in processing speed were attenuated in both short sleep groups.

CONCLUSIONS

In young adults, more variable short sleep schedules incorporating days of prophylactic or recovery sleep might mitigate compounding vigilance deficits resulting from recurrent cycles of sleep restriction. However, processing speed and subjective sleepiness were still impaired in both short sleep schedules. Getting sufficient sleep consistently is the only way to ensure optimal neurobehavioral functioning.

CLINICAL TRIAL

Performance, Mood, and Brain and Metabolic Functions During Different Sleep Schedules (STAVAR), https://www.clinicaltrials.gov/study/NCT04731662, NCT04731662.

The Contribution of Psychological Symptoms to Cognitive Difficulties in Youth With Postural Orthostatic Tachycardia Syndrome and Chronic Pain

INTRODUCTION

Subjectively experienced cognitive difficulties are common in youth with postural orthostatic tachycardia syndrome. The pathophysiological and psychological contributions of these cognitive impairments remain unclear.

METHOD

Participants were 96 adolescents and young adults diagnosed with postural orthostatic tachycardia syndrome and admitted to an intensive pain treatment program. Participants completed cognitive assessment and measures of postural orthostatic tachycardia syndrome symptoms, pain intensity, pain catastrophizing, anxiety, depression, and functional disability.

RESULTS

Self-reported autonomic symptom intensity, but not severity of heart rate change, was associated with cognitive performance. Symptoms of depression were associated with decreases in most measures of cognitive functioning. Pain intensity, pain catastrophizing, and depression but not cognitive scores and physiological measures, were significant predictors of disability.

CONCLUSION

Depression appears to be a significant contributor to the cognitive difficulties in youth with postural orthostatic tachycardia syndrome. These findings highlight the importance of assessing and treating affective symptoms in this population along with medical and lifestyle approaches to treating postural orthostatic tachycardia syndrome symptoms.

The effects of sustained mild sleep restriction on stress and distress among healthy adults: Findings from two randomized crossover studies

OBJECTIVE/BACKGROUND

Experimental studies suggest that sleep loss affects psychological outcomes. However, most studies focus on acute severe in-laboratory sleep restriction, with limited ecological validity. This study examines the impact of sustained mild sleep restriction (SR) on stress and distress among healthy adults in a naturalistic home environment.

PATIENTS/METHODS

We analyzed data from two randomized crossover studies. Individuals who regularly slept 7-9 h/night completed two 6-wk intervention phases separated by a 6-wk washout: habitual sleep (HS: maintenance of habitual bed and wake times) and SR (delayed bedtime by 1.5 h/night and maintenance of habitual wake time). Adherence to sleep duration requirements was verified with wrist actigraphy and daily sleep diaries during each intervention phase. Measures of perceived stress, subjective anxiety, subjective depression, rumination, and cortisol were collected at baseline and endpoint of each intervention phase.

RESULTS

Sixty-two participants (age 36.4 ± 14.0 y, 85.5 % women, 63.3 % racial/ethnic minority) were included in our analyses. Mean total sleep time was 7.4 ± 0.4 h/night during HS and 6.2 ± 0.4 h/night during SR (p < 0.001). Higher perceived stress (3.6 ± 1.0, p = 0.0007) and subjective anxiety (1.1 ± 0.5, p = 0.039) were observed after SR compared to HS. No effect of sleep condition was observed on subjective depression, rumination, and cortisol.

CONCLUSIONS

Our findings suggest that prolonged mildly insufficient sleep, similar to what commonly experienced in the real world, can lead to increased perceived stress and subjective anxiety in healthy adults. Addressing sleep loss, even if mild, should be a key component of interventions aimed at promoting mental health in the general population.

When Night Falls Fast: Sleep and Suicidal Behavior Among Adolescents and Young Adults

Sleep disturbances have been linked to suicidal ideation and behaviors in adolescents. Specifically, insomnia and nightmares are associated with current suicide risk and predict future ideation. Associations between hypersomnia, sleep apnea, and suicide remain inconclusive. Potential biological mechanisms underlying these relationships include executive functioning deficits and hyperarousal. Related psychological factors may include thwarted belongingness, perceived burdensomeness, and negative appraisals. Assessing suicide risk in patients with sleep disturbances, and vice versa, is needed. Therapeutic interventions such as cognitive behavior therapy for insomnia and imagery rehearsal treatment, as well as pharmacologic treatments, show promise in treating sleep disorders and suicidal behavior.

Middle childhood and adolescence sleep duration and behavior problems in adolescence

We examined the associations of middle childhood and adolescence nighttime sleep duration with adolescence internalizing and externalizing behavior problems per the Youth Self-Report (YSR) and the Child Behavior Checklist (CBCL) questionnaires, in a cohort of 889 Colombian schoolchildren. We estimated adjusted differences with 95% confidence intervals (CI) in mean behavior problem t-scores in standardized units between recommended sleep duration categories and as a continuous exposure using multiple linear regression and restricted cubic spline models, respectively. Compared with sleep duration within recommendations, middle childhood sleep above recommendations was related to 4.6 (95% CI: 1.6, 7.6; p = .004) and 5.4 (95% CI: 1.2, 9.7; p = .01) adjusted units higher YSR and CBCL externalizing problem scores, respectively. In continuous exposure analyses, this association seemed restricted to children aged ≥11 years. Longer sleep, both in categories and as a continuous exposure, was also associated with increased CBCL internalizing problems. Results did not differ by sex or weekend/weekday sleep. Sleeping under recommendations in middle childhood was not significantly related to behavior problems; nevertheless, shorter sleep in adolescence, in both categorical and continuous scales, was significantly related to behavior problems. In conclusion, behavior problems in adolescence are associated with longer sleep in middle childhood and shorter sleep in adolescence.

Response uncertainty influences response bias in the sustained attention to response task: a signal detection theory perspective

In the current investigation, we modified the high Go, low No-Go Sustained Attention to Response Task (SART) by replacing the single response on Go trials with a dual response to increase response uncertainty. In three experiments, a total of 80 participants completed either the original SART with no response uncertainty regarding the Go stimuli, or versions of the dual response SART in which response probabilities for the two possible responses to the Go stimuli varied from 0.9-0.1, 0.7-0.3, to 0.5-0.5. This resulted in a scale of increasing response uncertainty based on information theory to the Go stimuli. The probability of No-Go withhold stimuli was kept.11 in all experiments. Using the Signal Detection Theory perspective proposed by Bedi et al. (Psychological Research: 1-10, 2022), we predicted that increasing response uncertainty would result in a conservative response bias shift, noted by decreased errors of commission and slower response times to both Go and No-Go stimuli. These predictions were verified. The errors of commission in the SART may not be a measures of conscious awareness per se, but instead indicative of the level of participant trigger happiness-the willingness to respond quickly.

Sleep Deficits Inter-Link Lower Basal Forebrain-Posterior Cingulate Connectivity and Perceived Stress and Anxiety Bidirectionally in Young Men

BACKGROUND

The basal nucleus of Meynert (BNM), a primary source of cholinergic projections to the cortex, plays key roles in regulating the sleep-wake cycle and attention. Sleep deficit is associated with impairment in cognitive and emotional functions. However, whether or how cholinergic circuit, sleep, and cognitive/emotional dysfunction are inter-related remains unclear.

METHODS

We curated the Human Connectome Project data and explored BNM resting state functional connectivities (rsFC) in relation to sleep deficit, based on the Pittsburgh Sleep Quality Index (PSQI), cognitive performance, and subjective reports of emotional states in 687 young adults (342 women). Imaging data were processed with published routines and evaluated at a corrected threshold. We assessed the correlation between BNM rsFC, PSQI, and clinical measurements with Pearson regressions and their inter-relationships with mediation analyses.

RESULTS

In whole-brain regressions with age and alcohol use severity as covariates, men showed lower BNM rsFC with the posterior cingulate cortex (PCC) in correlation with PSQI score. No clusters were identified in women at the same threshold. Both BNM-PCC rsFC and PSQI score were significantly correlated with anxiety, perceived stress, and neuroticism scores in men. Moreover, mediation analyses showed that PSQI score mediated the relationship between BNM-PCC rsFC and these measures of negative emotions bidirectionally in men.

CONCLUSIONS

Sleep deficit is associated with negative emotions and lower BNM rsFC with the PCC. Negative emotional states and BNM-PCC rsFC are bidirectionally related through poor sleep quality. These findings are specific to men, suggesting potential sex differences in the neural circuits regulating sleep and emotional states.

Subjective and neural reactivity during savoring and rumination

Repetitive thinking about negative emotions or events is strongly associated with worse mental health, whereas repetitive positive thought is generally believed to be beneficial. This observation is at odds with the idea that all forms of repetitive thinking share underlying neural mechanisms. To resolve this apparent discrepancy, the present study examined relationships between subjective affect and neural mechanisms during periods of sustained processing of positive (savoring) and negative (rumination) emotion. We also examined potential common moderators of savoring and rumination including memory specificity and sleep quality. Results indicated that individuals who experience high positive affect during savoring also are likely to experience more intense negative affect during rumination. fMRI-derived brain activity revealed common mechanisms of rumination and savoring. Memory specificity had common effects on neural correlates of rumination and savoring; sleep quality was not associated with mechanisms of savoring or rumination. These results suggest that repetitive engagement with positive and negative affect is similar both subjectively and mechanistically. Clinical interventions for rumination may benefit from capitalizing on preserved capacity for savoring.

Adolescent social media use: cultivating and constraining competence

According to self-determination theory competence is a basic psychological need that is crucial for wellbeing. Social contexts strongly influence whether competence is supported or thwarted. Given that social media is a pervasive social context within adolescents' lives, it can play a crucial role in competence development. Three qualitative methods were used to investigate mid-adolescents' perspectives of how their social media use impacts competence. Participants included 36 students aged 15 years from four Australian schools. All participants completed a rich picture mapping activity and focus group discussions. A sub-sample of 11 students participated in follow-up interviews. Reflexive thematic analysis generated two overarching themes. The first theme cultivating competence includes sub-themes; enhancing social competencies, mastery experiences and goal accomplishment, and social media expertise. The second theme constraining competence includes sub-themes; ineffectance within the social media environment, interfering with sleep, and hindering learning. Findings demonstrated that social media contributes to today's adolescents encountering unique experiences with regards to competence development. Furthermore, adolescents' interactions on social media have broad implications for competence within online and offline realms. This study identifies aspects of social media use that can be targeted to help adolescents engage with social media in ways that cultivate rather than constrain competence.

Assessing 'readiness' by tracking fluctuations in daily sleep duration and their effects on daily mood, motivation, and sleepiness

STUDY OBJECTIVES

Consumer sleep trackers issue daily guidance on 'readiness' without clear empirical basis. We investigated how self-rated mood, motivation, and sleepiness (MMS) levels are affected by daily fluctuations in sleep duration, timing, and efficiency and overall sleep regularity. We also determined how temporally specific these associations are.

METHODS

119 healthy university students (64 female, mean age = 22.54 ± 1.74 years) wore a wearable sleep tracker and undertook twice-daily smartphone-delivered ecological momentary assessment of mood, motivation, and sleepiness at post-wake and pre-bedtime timings for 2-6 weeks. Naps and their duration were reported daily. Nocturnal sleep on 2471 nights were examined using multilevel models to uncover within-subject and between-subject associations between sleep duration, timing, efficiency, and nap duration on following day MMS ratings. Time-lagged analyses examined the temporal specificity of these associations. Linear regression models investigated associations between MMS ratings and sleep variability, controlling for sleep duration.

RESULTS

Nocturnal sleep durations were short (6.03 ± 0.71 h), and bedtimes were late (1:42AM ± 1:05). Within-subjects, nocturnal sleep longer than a person's average was associated with better mood, higher motivation, and lower sleepiness after waking. Effects of such longer sleep duration lingered for mood and sleepiness till the pre-bedtime window (all Ps < .005) but did not extend to the next day. Between-subjects, higher intraindividual sleep variability, but not sleep duration, was associated with poorer mood and lower motivation after waking. Longer average sleep duration was associated with less sleepiness after waking and lower motivation pre-bedtime (all Ps < .05). Longer naps reduced post-nap sleepiness and improved mood. Controlling for nocturnal sleep duration, longer naps also associated with lower post-waking sleepiness on the following day.

CONCLUSIONS

Positive connections between nocturnal sleep and nap duration with MMS are temporally circumscribed, lending credence to the construction of sleep-based, daily 'readiness' scores. Higher sleep duration variability lowers an individual's post waking mood and motivation.

CLINICAL TRIAL ID

ClinicalTrials.gov NCT04880629.