Effect of chronic sleep restriction on sleepiness and working memory in adolescents and young adults

Latent Profiles and Transitions of Bedtime Procrastination Among Chinese College Students: The Predictive Roles of Anxiety, Depression, Problematic Smartphone Use and Self-Control

Background

Bedtime procrastination (BP) has become an important factor affecting individual well-being. This study aimed to assess the stability and changes in BP and examine risk and protective factors.

Methods

The study recruited 1423 respondents. Latent profile analysis was used to identify subgroups of BP and latent transition analysis to determine transition probabilities for each subgroup. Logistic regression examined associations between identified classes and related factors.

Results

Three subgroups of BP were identified. In terms of stability and changes, the moderate bedtime procrastination group showed the highest stability (66%), followed by the severe bedtime procrastination group (62.4%), and the mild bedtime procrastination group had a 52% probability of switching to moderate bedtime procrastination. In terms of influencing factors, more problematic phone use (PSU) (OR: 1.08; 95% CI = 1.05-1.12), more depression (OR: 1.17; 95% CI = 1.06-1.29) and anxiety (OR: 1.16; 95% CI = 1.05-1.28) are all factors that aggravate the transition from mild to moderate sleep procrastination. Similarly, PSU (OR: 1.15; 95% CI = 1.12-1.19), anxiety (OR: 1.10; 95% CI = 1.06-1.14), and depression (OR: 1.10; 95% CI = 1.06-1.14) increased the risk of severe bedtime procrastination. Self-control emerged as a protective factor against BP.

Conclusion

This study identified three subgroups of BP at two time points and the rule of transition for each subgroup. Our findings indicate that BP were relatively stable, with some changes over time. The results also highlight the important function that PSU, depression, anxiety, and self-control can play in preventing and intervening in BP.

The effects of insufficient sleep and adequate sleep on cognitive function in healthy adults

STUDY OBJECTIVES

Although sleep affects a range of waking behaviors, the majority of studies have focused on sleep loss with relatively little attention on sustained periods of adequate sleep. The goal of this study was to use an experimental design to examine the effect of both of these sleep patterns on cognitive performance in healthy adults.

METHODS

This study used a randomized crossover design. Participants who regularly slept 7-9 hours/night completed two 6-week intervention conditions, adequate sleep (maintenance of habitual bed/wake times) and insufficient sleep (reduction in sleep of 1.5 hours relative to adequate sleep), separated by a 2-6weeks (median=43days) washout period. Cognitive functioning was evaluated at baseline and endpoint of each intervention using the NIH Toolbox Cognition Battery. General linear models contrasted scores following each condition to the baseline of the first condition; the baseline of the second condition was included to evaluate practice effects.

RESULTS

Sixty-five participants (age 35.9 ± 4.9years, 89% women, 52% non-White race/ethnicity) completed study procedures. There was improvement in performance on the List Sorting Working Memory task after the adequate sleep condition that exceeded practice effects. Cognitive performance after insufficient sleep did not reach the level expected with practice and did not differ from baseline. A similar pattern was found on the Flanker Inhibitory Control and Attention task.

CONCLUSIONS

These findings contribute to our understanding of the complex interplay between sleep and cognition and demonstrate that consistent, stable sleep of at least 7 hours/night improves working memory and response inhibition in healthy adults.

CLINICAL TRIAL REGISTRATION

The manuscript reports on data from two clinical trials: Impact of Sleep Restriction on Performance in Adults (URL: https://clinicaltrials.gov/ct2/show/NCT02960776, ID Number: NCT02960776) and Impact of Sleep Restriction in Women (URL: https://clinicaltrials.gov/ct2/show/NCT02835261, ID Number: NCT02835261).

Sleep disturbances in children and adolescents with type 1 diabetes mellitus: Prevalence, and relationship with diabetes management

OBJECTIVE

A decline in sleep quality and regularity has been reported in patients with type 1 diabetes mellitus (T1D) in many studies. However, research on medical-based sleep disorders in patients with T1D is limited. Diagnosing sleep disorders is crucial, as it negatively impacts academic performance, cardiovascular health, and cognitive functions among children as well as essential skills for effective diabetes management. Our objective was to assess sleep disturbances in patients diagnosed with T1D and explore whether these patients experience significantly more sleep disturbances compared to their healthy peers.

METHODS

This study, designed as a cross-sectional case-control investigation, involved a cohort of 250 participants (144 T1D, 106 control cases) aged 6-15 years. The Sleep Disturbance Scale for Children (SDCS) scores of the T1D group were compared with those of the control group. Furthermore, the study explored the correlation between clinical/biochemical parameters and SDCS scores within the T1D group.

RESULTS

The mean age of individuals in the T1D group was 10.27 ± 3.25 years, while the control group had a comparable mean age of 10.48 ± 3.5 years (P = 0.303). Within the T1D group, the median duration of diabetes was 5 (1-15) years, and the median glycosylated hemoglobin A1c (HbA1c) level for the past one year was 8.4 %. Although there was no significant difference in total SDSC scores between the T1D and control groups, both groups exhibited average scores that remained close to the threshold indicative of sleep disturbances (>39). Notably, individuals with total SDSC scores surpassing 39 were identified at rates of 48.6 % in the T1D group and 47.6 % in the control group, respectively. Furthermore, disorders of arousal nightmares (DA) were more prevalent in T1D patients compared to their healthy peers (P = 0.049). Additionally, HbA1c showed a positive correlation with scores for disorders of excessive somnolence (DOES) and total scores (P < 0.001, R = 0.368; P = 0.003, R = 0.243).

CONCLUSION

Our study found that the prevalence of sleep disturbances among children and adolescents with T1D was not significantly higher than that observed in their healthy peers. Nevertheless, it is crucial to note that a notable portion, 48.6 % of T1D cases and 47.6 % of healthy cases, displayed sleep disturbances based on SDSC scores. To optimize diabetes management and proactively address potential challenges, incorporating routine screening for sleep disturbances in the monitoring of T1D patients can yield valuable benefits.

Human Derived Dermal Fibroblasts as in Vitro Research Tool to Study Circadian Rhythmicity in Psychiatric Disorders

A number of psychiatric disorders are defined by persistent or recurrent sleep-wake disturbances alongside disruptions in circadian rhythm and altered clock gene expression. Circadian rhythms are present not only in the hypothalamic suprachiasmatic nucleus but also in peripheral tissues. In this respect, cultures of human derived dermal fibroblasts may serve as a promising new tool to investigate cellular and molecular mechanisms underlying the pathophysiology of mental illness. In this article, we discuss the advantages of fibroblast cultures to study psychiatric disease. More specifically, we provide an update on recent advances in modeling circadian rhythm disorders using human fibroblasts.

"I need to be alert at night to provide care": Factors associated with problematic sleep among young Australian caregivers

OBJECTIVES

There is increased recognition that young people (<25 years) may occupy a carer role for family or others with health conditions or disability. This is often in addition to study and social activities. This means competing demands on time, and insufficient sleep. Our aim was to determine the contribution of caring duties to problematic sleep in young carers.

METHODS

A survey of Australian carers was conducted, including questions on demographics, characteristics of the carer and care recipient, and sleep quality and quantity. Participants were eligible if they reported sleep time <7 hr or dissatisfaction with their sleep, and were aged 15-24 years.

RESULTS

A total of 110 participants (71.8%_female = 79, 15-17 years = 62, 18-24 years = 48) were included in analysis; 55.5% (n= 61) reporting dissatisfaction with their sleep and 62.7% (n= 69) reporting typically less than 7 hr sleep per night. Sleep duration was significantly shorter for those who reported 1-2 or ≥3 awakenings to provide care, compared with no awakenings (p_< .05). Sleep quality, as described by scores on the Pittsburgh Sleep Quality Index (PSQI) was also significantly worse for those who were frequently awoken by their care recipient (p < .05). Worrying about the care recipient, being woken by the care recipient, and listening out for the care recipient were the most frequently identified factors impacting on sleep.

CONCLUSION

Young carers experience reduced sleep duration and poor sleep quality. Strategies to alleviate the burden of care work on young carer's sleep would benefit the health and safety of this group.

Extending sleep to improve glycemia: The Family Routines Enhancing Adolescent Diabetes by Optimizing Management (FREADOM) randomized clinical trial protocol

Sleep deficiencies amongst individuals with type 1 diabetes mellitus (T1DM) have been linked with dysregulated glycemic control and greater morbidities. Sleep extension (EXT) has been identified as a viable intervention target to improve adolescent outcomes. The intervention aims to emphasize collaborative work with families to engage in behaviors that increase the likelihood of the youth increasing their sleep duration consistently. This study will randomize up to 175 youth with T1DM and at least one caregiver to either an EXT intervention or a family routines support (FRS) consultation. It is hypothesized that the EXT condition will lead to improvements in sleep, which in turn, will contribute to improved glycemic control. The primary endpoint is improved glycemic control assessed via a continuous glucose monitor (CGM) to ascertain average glucose levels across a week, glycemic variability, and percent time in the target range at one month and HbA1c at three months. Analyses will control for co-morbid conditions, including sleep-disordered breathing and obesity. This study will provide the needed data to support addressing sleep as part of the standards of care in youth with T1DM.

Sleep quality and creativity in Chinese college student during the COVID-19 pandemic: The mediating role of executive function

Background

COVID-19 has impacted adolescents' interpersonal relationships, life attitudes, and mental health during the past 3 years. However, previous studies predominantly focused on negative problems, while few studies assessed the situation of teenagers from the perspective of positive psychology. Therefore, this study explores the creativity level of Chinese college students during the COVID-19 pandemic, the relationship between sleep quality and creativity, and the mediating role of executive function.

Method

A cross-sectional study was conducted across six colleges in Heilongjiang in China, with a sample of 4,258 college students recruited via stratified cluster sampling. Data were collected through an online survey. A mediation model was constructed, and SPSS PROCESS macro was used to analyze the data.

Results

The creativity score of Chinese college students during the COVID-19 pandemic was 106.48 ± 13.61. Correlation analysis demonstrated that sleep quality correlated negatively with creativity (r = -0.08, P < 0.01) but positively with executive function (r=0.45, P < 0.01), whilst executive function correlated negatively with creativity (r = -0.10, P < 0.01). Moreover, the mediation model revealed that executive function partially mediated the relationship between sleep quality and creativity in college students (indirect effect = -0.017, SE = 0.004, 95% CI = [-0.025, -0.008]). Executive function accounted for 48.6% of the variance in college students' creativity.

Conclusion

School administrators should implement measures such as sleep education to enhance students' sleep quality. Concurrently, curriculum and assessment implementation should enhance executive function. Such measures can contribute to improved student creativity, thus helping students overcome the negative emotional impact of the COVID-19 pandemic.

Effects of partial sleep deprivation on prefrontal cognitive functions in adolescents

Purpose

The effect of sleep deprivation on cognitive functions associated with the frontal lobe, such as attention, executive functions, and working memory, is not well known. This study aimed to investigate the effect of partial sleep deprivation in adolescents on the cognitive tasks of the frontal lobe, including visuospatial working memory, processing speed, sustained attention, executive functions, and short-term visual memory.

Methods

Participants were recruited from voluntary students of Çukurova University. Eighteen adolescents underwent four consecutive nights of monitored sleep restriction (6-6.5 h/night) and four nights of sleep extension (10-10.5 h/night) in a counterbalanced order and separated by a washout period. Following each sleep period, the cognitive performance was assessed, at a fixed morning time, using a computerized neuropsychological test battery based on frontal lobe functions tasks, which was a timed test providing both accuracy and reaction time outcome measures.

Results

Only the spatial working memory performance of cognitive tasks was found to be statistically lower in the restricted-sleep condition than in the extended-sleep condition (p < 0.05). No significant difference was found in the performance of cognitive tasks evaluating simple attention, constant attention, executive functions, and cognitive flexibility.

Conclusions

The findings of this study indicated that partial sleep restriction negatively affects specifically working memory and strategic thinking skills among cognitive functions based on the frontal lobe. Especially the visuospatial working memory and strategic thinking skills of adolescents might be susceptible to chronic partial sleep deprivation.

Gene Expression Changes of Murine Cortex Homeostasis in Response to Sleep Deprivation Hint Dysregulated Aging-like Transcriptional Responses

Sleep deprivation leads to the deterioration in the physiological functioning of the brain, cognitive decline, and many neurodegenerative diseases, all of which progress with advancing age. Sleep insufficiency and impairments in cognitive function are characterized by progressive neuronal losses in the cerebral cortex. In this study, we analyze gene expression profiles following sleep-deprived murine models and circadian matched controls to identify genes that might underlie cortical homeostasis in response to sleep deprivation. Screening of the literature resulted in three murine (Mus musculus) gene expression datasets (GSE6514, GSE78215, and GSE33491) that included cortical tissue biopsies from mice that are sleep deprived for 6 h (n = 15) and from circadian controls that are left undisturbed (n = 15). Cortical differentially expressed genes are used to construct a network of encoded proteins that are ranked based on their interactome according to 11 topological algorithms. The analysis revealed three genes-NFKBIA, EZR, and SGK1-which exhibited the highest multi-algorithmic topological significance. These genes are strong markers of increased brain inflammation, cytoskeletal aberrations, and glucocorticoid resistance, changes that imply aging-like transcriptional responses during sleep deprivation in the murine cortex. Their potential role as candidate markers of local homeostatic response to sleep loss in the murine cortex warrants further experimental validation.

Effects of an afternoon nap on sustained attention and working memory: The role of physiological arousal and sleep variables

Taking a short midday nap has been associated with higher alertness and better cognitive task performance. Yet, the mechanisms associated with nap-dependent performance enhancement are unclear. The current study was conducted to explore the impact of physiological arousal during cognitive task and sleep architecture during a pre-task nap on post-nap behavioral outcomes. A within-subjects design (N = 18) was employed, in which participants either took a nap or remained awake for 40 min during the post-lunch period. The psychomotor vigilance test (PVT) and n-back task were administered to assess sustained attention and working memory, respectively, with each task including one block of easy trials and one block of difficult trials. Results showed that a short midday nap improved sustained attention but not working memory. In addition, a midday nap induced lower physiological arousal during the performance on both cognitive tasks, with relatively higher delta and lower beta activity. The relative power of theta and alpha were positively correlated with performance on the easy PVT, whereas the alpha power was negatively correlated with performance on the difficult PVT, and the theta power was negatively correlated with reaction speed in the n-back task regardless of the task difficulty. Meanwhile, the shorter total sleep time and longer time of wake after sleep onset were associated with the faster overall reaction speed in PVT easy trials. These findings suggested that both changes in physiological arousal and sleep variables might account for changes in task performance after a short midday nap.

Effect of Self-Efficacy on Bedtime Procrastination Among Chinese University Students: A Moderation and Mediation Model

Bedtime procrastination (BP) is generally considered to be a maladaptive behavior. However, BP may be an adaptive fast LH strategy within the LH framework, and further, personal beliefs about their abilities and resources promote this fast LH strategy. Here, the present study addressed this idea, focusing on the effect of self-efficacy on BP, the mediation of harm avoidance (HA), and the moderation of novelty seeking (NS). Data from 552 Chinese university students (205 men and 347 women) were analyzed using SPSS 25.0 and SPSS PROCESS Macro. Results indicated that HA partially mediates the relationship between self-efficacy and BP. Main interactional effects have been observed when NS is introduced in the model as a moderator. Implications and limitations of the study and suggestions for further study are discussed.

Indirect Associations Between Self-Rated Alertness and Recall via Strategic and Nonstrategic Factors

Excessive daytime sleepiness is associated with reduced cognitive functioning in children and adolescents. The present study was an initial examination of direct and indirect associations between sleep and recall via strategic and nonstrategic memory processes in a sample of 66 participants from grades 1, 3, 5, and college. Stimuli varied in familiarity and presence of a strategy prompt. Strategy use during encoding and during recall were measured separately. The present study predicted that alertness would be associated with both strategic and nonstrategic factors related to memory, alertness would predict recall indirectly via strategic and nonstrategic factors (controlling for grade and gender), and this indirect path would be moderated by grade. The first 2 hypotheses were partially supported; the third was not. Self-reported alertness associated weakly with speed of tapping and with strategy use during encoding on the first trial (familiar words, no strategy cue). Analysis indicated an indirect effect via strategy use during encoding on Trial 1 but via speed of tapping on Trial 3. Tests of moderated mediation were not significant on any trial, indicating that the indirect pathways were not moderated by grade. Alertness may influence recall via strategic or nonstrategic processes, and its role may depend on familiarity and availability of strategy cues. Several proposed research directions are suggested for future exploration.

Interindividual differences in attentional vulnerability moderate cognitive performance during sleep restriction and subsequent recovery in healthy young men

We investigated whether interindividual attentional vulnerability moderates performance on domain-specific cognitive tasks during sleep restriction (SR) and subsequent recovery sleep. Fifteen healthy men (M ± SD, 22.3 ± 2.8 years) were exposed to three nights of baseline, five nights of 5-h time in bed SR, and two nights of recovery sleep. Participants completed tasks assessing working memory, visuospatial processing, and processing speed approximately every two hours during wake. Analyses examined performance across SR and recovery (linear predictor day or quadratic predictor day²) moderated by attentional vulnerability per participant (difference between mean psychomotor vigilance task lapses after the fifth SR night versus the last baseline night). For significant interactions between day/day² and vulnerability, we investigated the effect of day/day² at 1 SD below (less vulnerable level) and above (more vulnerable level) the mean of attentional vulnerability (N = 15 in all analyses). Working memory accuracy and speed on the Fractal 2-Back and visuospatial processing speed and efficiency on the Line Orientation Task improved across the entire study at the less vulnerable level (mean − 1SD) but not the more vulnerable level (mean + 1SD). Therefore, vulnerability to attentional lapses after SR is a marker of susceptibility to working memory and visuospatial processing impairment during SR and subsequent recovery.

A Study to See the Effect of Social Media Usage Among Healthcare Providers

Purpose

This study aimed to assess how healthcare professionals (HCPs) use social media to determine how it influences the quality of patient care.

Materials and methods

This is a cross-sectional study conducted over eight months, between August 2020 and March 2021 using a questionnaire and checked amongst investigators.

Results

One hundred fifty-eight participants had electronic devices and 145 (91.9%) used social media at work. 26.6% of these HCPs said they spent less than an hour on social media forums, 31% said they spent one to two hours, 28.5% said two to three hours, and 13.9% said they spent more than four hours. As compared to nurses (46%), consultants and pharmacists use social media at a much lower rate (1% for each group). Compared to junior doctors, a higher percentage of nurses (40%) said they were aware of a social media policy at their hospital (8%). A quarter of healthcare employees (20%) were unaware of their workplace policy, potentially exposing sensitive medical details to the public. More research is needed to assess the particular effects of these results on patient care quality and can help in providing literature informing applications encrypted and secure patient data.

Conclusion

According to our results, a large percentage of healthcare quality professionals used social media networks. A significant proportion of doctors and nurses use it to visit online medical forums for improving education. A large portion of surveyed sample was unaware of hospital policy on social media usage. Further education is required to improve the right use of social media in the hospital setting.

Sleep timing and consistency are associated with the standardised test performance of Icelandic adolescents

Sleep has been shown to affect cognitive function in laboratory studies; however, its association to the academic performance of adolescents has largely been demonstrated using self-reported measures. Studies with objective measures of both sleep and academic performance are limited. The aim of the present study was to determine whether the free-living sleep quantity, quality, and timing of 15-year-old adolescents measured with wrist actiography are associated with their scores on national standardised examinations as an objective measure of academic achievement. We measured sleep with wrist actiography for 1 week in 253 (150 girls) Icelandic adolescents with a mean (SD) age of 15.9 (0.3) years. Multiple linear regression was used to assess associations between sleep parameters and combined standardised examination scores in mathematics, English, and Icelandic obtained from the Icelandic Directorate of Education. We found that students went to bed at 00:49 hours (± 51.8 min) and slept for a mean (SD) of 6.6 (0.7) hr/night, with a median (interquartile range) night-to-night variation in sleep duration of 1.2 (0.7) hr and an efficiency of 88.1 (5.3)%. Combined analyses adjusted for sex, demonstrated that both bedtime and night-to-night variability in total sleep time were negatively associated with the average score across all topics. Sex-specific associations did not indicate clear differences between boys and girls. These findings suggest that, in addition to appropriate sleep duration, public health guidance should also highlight the importance of early and consistent sleep schedules to academic achievement for both boys and girls.

Sleep duration and mood in adolescents: an experimental study

STUDY OBJECTIVES

This study examines the relationship between experimentally manipulated sleep duration and mood in adolescents.

METHODS

Thirty-four adolescents (20 male), aged 15-17 years, lived in a sleep laboratory for 10 days and 9 nights. They were allocated to one of three sleep "doses" for five consecutive nights for 5, 7.5, or 10 h sleep opportunity per night. Two baseline nights and two recovery nights entailed 10 h sleep opportunity per night. Mood was measured every 3 h during wake using unipolar visual analogue scales measuring the mood states "depressed," "afraid," "angry," "confused," "anxious," "happy," and "energetic."

RESULTS

Mixed models analyses with post hoc comparisons revealed that participants in the 5-h group, but not the 7.5- or 10-h groups, reported being significantly more depressed, angry, and confused during sleep restriction than at baseline. Adolescents were significantly less happy and energetic during sleep restricted to 5 h and significantly less energetic during sleep restricted to 7.5 h. When adolescents had 10 h sleep opportunities their happiness significantly increased. No statistically significant effects of sleep restriction were found for fear or anxiety, although small-to-moderate effects of sleep restricted to 5 or 7.5 h were found. Two nights of recovery sleep was not sufficient to recover from increased negative mood states for the 5-h group, although recovery occurred for positive mood states.

CONCLUSIONS

Given the prevalence of insufficient sleep and the rising incidence of mood disorders and dysregulation in adolescents, these findings highlight the importance of sufficient sleep to mitigate these risks.

How much sleep do you need? A comprehensive review of fatigue related impairment and the capacity to work or drive safely

In developed countries, deaths attributable to driving or working while intoxicated have steadily declined over recent decades. In part, this has been due to (a) public education programs about the risks and (b) the deterrence value associated with penalties and prosecutions based on an individual being 'deemed impaired' if they exceed a proscribed level of blood alcohol or drug concentration while driving/working. In contrast, the relative proportion of fatigue-related accidents have remained stubbornly high despite significant public and workplace education. As such, it may be useful to introduce the legal principle of 'deemed impaired' with respect to fatigue and/or sleep loss. A comprehensive review of the impairment and accident literature was performed, including 44 relevant publications. Findings from this review suggests that a driver or worker might reasonably be 'deemed impaired' once the amount of sleep falls below five hours in the prior 24. Building on the legal principles first outlined in recent New Jersey legislation (Maggie's Law), this review argues that an individual can reasonably be 'deemed impaired' based on prior sleep wake behaviour. In Maggie's Law, a driver can be indirectly 'deemed impaired' if they have not slept in the prior 24 h. Based on the extant literature, we argue that, relative to drug and alcohol intoxication, this may be overly conservative. While roadside measurement of fatigue and prior sleep-wake behavior is not yet possible, we suggest that public education programs should provide specific guidance on the amount of sleep required and that post-accident forensic examination of prior sleep wake behaviours may help the community to determine unsafe behaviours and liability more objectively than is currently the case.

Adverse interaction effects of chronic and acute sleep deficits on spatial working memory but not on verbal working memory or declarative memory

The accumulation of chronic sleep deficits combined with acute sleep loss is common in shift workers and increases the risk of errors and accidents. We investigated single and combined effects of chronic and acute sleep loss and recovery sleep on working memory performance (N-back task) and on overnight declarative memory recall (paired-associate lists) in 36 healthy participants. After baseline measurements, the chronic sleep restriction group (n = 21; mean [SD] age 26 [4] years) underwent 5 nights of sleep restriction (5-hr time in bed [TIB]), whereas the control group (n = 15; mean [SD] age 28 [6] years) had 8-hr TIB during those nights. Afterwards, both groups spent 1 night with 8-hr TIB prior to acute sleep deprivation for 38 hr, and a final recovery night (10-hr TIB). Chronic sleep restriction decreased spatial N-back performance compared to baseline (omissions: p = .001; sensitivity: p = .012), but not letter N-back performance or word-pair recall. Acute sleep deprivation impaired spatial N-back performance more in the chronic sleep restriction group than in the control group (interaction between group and time awake: p ≤ .02). No group differences during acute sleep loss appeared in letter N-back performance or word recall. It is concluded that chronic sleep loss, even when followed by a night of recovery sleep, increases the vulnerability to impairments in spatial working memory during subsequent acute sleep loss. Verbal working memory and declarative memory were not affected by restricted sleep.

Association between free-living sleep and memory and attention in healthy adolescents

In laboratory studies, imposed sleep restriction consistently reduces cognitive performance. However, the association between objectively measured, free-living sleep and cognitive function has not been studied in older adolescents. To address this gap, we measured one week of sleep with a wrist-worn GT3X+ actigraph in 160 adolescents (96 girls, 17.7 ± 0.3 years) followed by assessment of working memory with an n-back task and visual attention with a Posner cue-target task. Over the week, participants spent 7.1 ± 0.8 h/night in bed and slept 6.2 ± 0.8 h/night with 88.5 ± 4.8% efficiency and considerable intra-participant night-to-night variation, with a standard deviation in sleep duration of 1.2 ± 0.7 h. Sleep measures the night before cognitive testing were similar to weekly averages. Time in bed the night before cognitive testing was negatively associated with response times during the most challenging memory task (3-back; p = 0.005). However, sleep measures the night before did not correlate with performance on the attention task and weekly sleep parameters were not associated with either cognitive task. Our data suggests shorter acute free-living sleep may negatively impact difficult memory tasks, however the relationship between free-living sleep and cognitive task performance in healthy adolescents is less clear than that of laboratory findings, perhaps due to high night-to-night sleep variation.

The impact of reduced sleep on school related outcomes for typically developing children aged 11–19: A systematic review

This systematic literature review examines the relationship between restricted and reduced sleep and school performance, learning and cognitive functioning in typically developing adolescents. Correlational and experimental data were evaluated from 17 studies which included participants ranging from 11 to 19 years in studies from seven countries around the world. The review found that there is evidence that restricted and reduced sleep is negatively associated with school performance and cognitive outcomes, although the findings were mixed. Implications for psychologists working with schools are discussed. More research and evaluation is needed to establish how these factors relate to each other conclusively.

Sleepiness, Neuropsychological Skills, and Scholastic Learning in Children

Excessive daytime sleepiness is a frequent condition among children and adolescents that may lead to several and significant daytime consequences, including impaired neurocognitive skills and scholastic performance. Here, we evaluated in one hundred and ninety-one unselected primary school children, the relationship between sleepiness and a wide range of cognitive and academic skills through a standardized neuropsychological test battery. In order to assess the statistical relationship, we performed a partial least squares path modelling, a non-parametrical approach which combined a model of paths between latent variables and the coefficients between indicators and dimensions. Results were validated through the bootstrap approach and suggest that sleepiness is not associated with all cognitive and scholastic abilities, but only with those relying on verbal abilities and complex cognitive functions (i.e., reading comprehension, oral/syntactic comprehension, spelling, and mathematic skills). Our data suggest the idea that sleepiness in children is associated mostly with “higher” (mainly verbal) cognitive function(s), while the visuospatial domain was not affected.

Effects of insomnia symptoms and objective short sleep duration on memory performance in youths

Sleep quantity and quality are both important for optimal development and functioning during youth. Yet few studies have examined the effects of insomnia symptoms and objective short sleep duration on memory performance among adolescents and young adults. One-hundred and ninety participants (female: 61.6%) aged from 12 to 24 years completed this study. All participants underwent a clinical interview, a 7-day actigraphic assessment, a battery of self-report questionnaires and cognitive tests to assess working memory and episodic memory. Insomnia symptoms were defined as a score ≥ 9 on the Insomnia Severity Index, and objective short sleep duration was defined as average total sleep time less than 7 hr for those aged 12-17 years, and 6 hr for those aged 18 years and above as assessed by actigraphy. Insomnia symptoms were significantly associated with worse self-perceived memory (p < .05) and poorer performance on the digit span task (p < .01), but not the dual N-back task and verbal learning task. There was no significant difference in any of the memory measures between participants with objective short sleep duration and their counterparts. No interaction effect was found between insomnia and short sleep duration on any of the objective memory outcomes. Insomnia symptoms, but not objective short sleep duration, were associated with poorer subjective memory and objective working memory performance in youths. Further studies are needed to investigate the underlying mechanisms linking insomnia and memory impairments, and to delineate the long-term impacts of insomnia on other aspects of neurocognitive functioning in youth.

A split sleep schedule rescues short-term topographical memory after multiple nights of sleep restriction

Study Objectives

Chronic sleep restriction in adolescents is widespread, yet we know little about how to apportion the limited amount of sleep obtained to minimize cognitive impairment: should sleep occur only nocturnally, or be split across separate nocturnal and daytime nap periods? This is particularly relevant to hippocampal-dependent cognitive functions that underpin several aspects of learning.

Method

We assessed hippocampal function in four groups by evaluating short-term topographical memory with the Four Mountains Test (4MT). All participants began with 9 hours nocturnal time-in-bed (TIB) for 2 days before following different sleep schedules over the next 3 days. Each day, one group had 5 hours nocturnal TIB (5.0h; n = 30), another, 6.5 hours nocturnal TIB (6.5h; n = 29), and a third had 6.5 hours split into 5 hours nocturnal TIB and a 1.5 hour TIB daytime nap (5.0 + 1.5h; n = 29). A control group maintained 9 hours nocturnal TIB (9.0h; n = 30). The 4MT was administered mid-afternoon (1.5 hours after awakening for those who napped).

Results

Performance of the 5.0h and 6.5h nocturnal TIB groups was significantly impaired relative to the 9.0h control group. Performance of participants on the split- sleep schedule (5.0 + 1.5h) did not significantly differ from controls.

Conclusions

These findings suggest that hippocampal function is sensitive to moderate multi-night sleep restriction, but deficits can be ameliorated by splitting sleep, at least for a period after waking from a daytime nap. While this split sleep schedule should not be considered a replacement for adequate nocturnal sleep, it appears to benefit the cognitive and neurophysiological functions that underpin learning in those who are chronically sleep deprived.

Sleep-related disorders in patients with type 1 diabetes mellitus: current insights

Type 1 diabetes mellitus (T1DM) is an autoimmune condition that results from destruction of beta cells in the pancreas. Several reviews have concluded that sleep contributes to poor glycemic control, diabetes management, and diabetes-related complications in individuals with T1DM and represents an untapped opportunity for intervention. However, at the current juncture, the American Diabetes Association's Standards of Medical Care are devoid of recommendations about how to address sleep in the management of T1DM. This article summarizes reviews of sleep in youth and adults with T1DM and empirical studies that have examined various sleep parameters ranging from sleep disturbances (general, perceived sleep quality, sleepiness, awakenings, and sleep efficiency), sleep duration, sleep consistency, sleep-disordered breathing (SDB), and sleep architecture. The data show that many individuals with T1DM sleep less than recommendations; individuals with the poorest sleep have difficulties with diabetes management; and sleep deficiency including SDB often corresponds to several disease morbidities (neuropathy, nephropathy, etc). Mixed findings exist regarding direct associations of various sleep parameters and glycemic control. SDB appears to be just as prevalent, if not more, than other conditions that have been recommended for universal screening in individuals with T1DM. The article concludes with recommendations for collaborative research efforts to further elucidate the role of sleep in diabetes-related outcomes; investigations to test behavioral strategies to increase sleep quantity and consistency; and considerations for clinical care to address sleep.

Annual Research Review: Educational neuroscience: progress and prospects

Educational neuroscience is an interdisciplinary research field that seeks to translate research findings on neural mechanisms of learning to educational practice and policy and to understand the effects of education on the brain. Neuroscience and education can interact directly, by virtue of considering the brain as a biological organ that needs to be in the optimal condition to learn ('brain health'); or indirectly, as neuroscience shapes psychological theory and psychology influences education. In this article, we trace the origins of educational neuroscience, its main areas of research activity and the principal challenges it faces as a translational field. We consider how a pure psychology approach that ignores neuroscience is at risk of being misleading for educators. We address the major criticisms of the field comprising, respectively, a priori arguments against the relevance of neuroscience to education, reservations with the current practical operation of the field, and doubts about the viability of neuroscience methods for diagnosing disorders or predicting individual differences. We consider future prospects of the field and ethical issues it raises. Finally, we discuss the challenge of responding to the (welcome) desire of education policymakers to include neuroscience evidence in their policymaking, while ensuring recommendations do not exceed the limitations of current basic science.

Maternal Executive Function and Sleep Interact in the Prediction of Negative Parenting

Objective/Background: Poorer executive function (EF) has been implicated in the etiology of negative parenting (e.g., harsh, reactive, intrusive). EF may be affected by good or poor quality sleep, and thus sleep may be involved in negative parenting. In the current exploratory study, we investigated the additive and interactive effects of maternal EF and sleep indicators in the statistical prediction of negative parenting. Patients/Methods: A sample of 241 mothers of 2.5-year-olds (51% girls) completed questionnaires, wore wrist actigraphs for one week, and completed several EF tasks during a laboratory visit. Results/Conclusions: We found that sleep activity (e.g., nighttime waking and movements) interacted with EF in predicting negative parenting practices, such that poorer EF was linked with more negative parenting only in the context of higher levels of night waking. Sleep duration also interacted with EF, such that EF and parenting were no longer associated when sleep durations were short. The findings have implications for incorporating sleep into our understanding of maternal cognitive self-regulation and harsh parenting during early childhood development.

Sleep, hippocampal volume, and cognition in adults over 90 years old

BACKGROUND

Several lines of research support associations between sleep and cognition in older adults. However, there is a paucity of data regarding sleep and cognition in nonagenarians and centenarians.

AIMS

The current study examined self-reported sleep quantity and sleep quality in relation to hippocampal volume and cognition in adults aged 90 and older.

METHODS

A total of 144 participants of The 90+ Study completed The Medical Outcomes Study sleep questionnaire. Participants reported subjective sleep duration in hours and three sleep quality factors: sleep problems, adequacy, and somnolence. Neuropsychological assessments of memory, global cognition, language, and executive function were completed, on average, 61 days from the questionnaire. Hippocampal volume on 3 T MRI, adjusted for intracranial volume, was obtained in 82 participants. We performed multiple linear regressions, controlling for age, sex, education, sleep medication, and depression, to examine sleep characteristics in relation to hippocampal volume and cognitive performance in all the subjects and then stratified by cognition.

RESULTS

Sleep duration > 8 h was associated with lower scores in tests of global cognition, memory, and executive function compared to sleep duration of 7-8 h when collapsing across cognitive status, but only with memory in cognitively impaired subjects, and not in cognitively normal subjects.

CONCLUSIONS AND DISCUSSION

Long-sleep duration is associated with poorer global cognition, memory, and executive function in the oldest-old, and is only associated with memory in cognitively impaired oldest-old. Additional research is necessary to determine if sleep duration is a risk factor or a result of poor cognition in advanced age.

A Community-Based Study of Sleep and Cognitive Development in Infants and Toddlers

STUDY OBJECTIVES

To examine the prevalence and correlates of nighttime awakenings and to explore the association between sleep and cognitive development in a community sample of infants and toddlers.

METHODS

A total of 590 healthy infants (aged 2-11 months) and 512 toddlers (aged 12-30 months) from 8 provinces of China were assessed for their sleep and cognitive development. Data on sleep duration and nighttime awakenings were collected through the Brief Infant Sleep Questionnaire. Cognitive development was assessed by trained pediatricians using the Bayley Scales of Infant Development.

RESULTS

Prevalence of no nighttime awakening, and nighttime awakening(s) for 1×/night, 2×/night, and ≥ 3×/night was 6.8%, 20.2%, 33.2%, and 39.3% in infants, and was 25.8%, 34.6%, 23.8%, and 15.8% in toddlers, respectively. Nighttime awakenings were generally associated with younger age, lower maternal education level, and being currently breastfed. In addition, nighttime awakenings were associated with being boys in toddlers. After controlling for potential confounders, infants with nighttime awakenings for 2×/night were found to have significantly higher Mental Development Index (MDI) score, as compared to those without and those with more frequent nighttime awakenings. However, toddlers with nighttime awakenings for ≥ 3×/night had significantly lower MDI, as compared to those with fewer nighttime awakenings. Total sleep duration was not associated with any developmental indices in both infants and toddlers.

CONCLUSIONS

Frequent nighttime awakenings are associated with poor cognitive functions in toddlers. Meanwhile, a nonlinear association between nighttime awakenings and cognitive performance was found among infants. The findings provide a developmental context for the effect of sleep on cognitive abilities in young children. Further longitudinal studies and interventional studies on the effects of parent-based sleep-focused intervention on cognitive abilities among young children are warranted.

The Impact of Sleep Restriction on Daytime Functioning in School-Age Children With and Without ADHD: A Narrative Review of the Literature

The purpose of this narrative review was to synthesize the existing literature on the impact of sleep on daytime functioning in both typically developing (TD) children and children with attention-deficit/hyperactivity disorder (ADHD). Correlational studies in children suggest that insufficient sleep and impaired daytime functioning are significantly associated; however, this does not address the causal relationships between sleep and daytime functioning. The review results indicated that there is limited experimental sleep manipulation research in children. In the eight studies that employed experimental methods to examine sleep restriction, the consequences of insufficient sleep were greatest for attention and inconsistent for other domains, such as cognition and emotion regulation. Despite the significant co-occurrence of ADHD and sleep problems, the experimental sleep research focused on the daytime impact of shorter sleep in children with ADHD is extremely limited and as such more research is needed.

Social Media Use Before Bed and Sleep Disturbance Among Young Adults in the United States: A Nationally Representative Study

Study Objectives

Social media (SM) use has been positively associated with disturbed sleep among young adults. However, previous studies have not elucidated the specific importance of SM use immediately before bed. We aimed to determine the independent association of SM use during the 30 minutes before bed and disturbed sleep while controlling for covariates including total SM use throughout the day.

Methods

We assessed a nationally representative sample of 1763 US young adults aged 19-32. Participants estimated to what extent they used SM in the 30 minutes before bed. We assessed sleep disturbance using the brief Patient-Reported Outcomes Measurement Information System (PROMIS®) Sleep Disturbance measure. After testing the proportional odds assumption, we used ordered logistic regression to compute the independent association between SM use before bed and sleep disturbance controlling for covariates, including total SM use.

Results

Compared with those who rarely or very rarely check SM in the 30 minutes before bed, those who often or very often check SM at that time had an adjusted odds ratio of 1.62 (95% confidence interval = 1.31-2.34) for increased sleep disturbance. Additionally, we found a significant linear trend in the odds ratios between the frequency of checking SM in the 30 minutes before bed and increased sleep disturbance (p = .007). Results were consistent in all sensitivity analyses.

Conclusions

SM use in the 30 minutes before bed is independently associated with disturbed sleep among young adults. Future work should use qualitative and experimental methods to further elucidate the directionality of-and mechanisms underlying-this association.

Exposure to video games: effects on sleep and on post-sleep cognitive abilities. A sistematic review of experimental evidences

The public opinion is ever more interested and worried about possible effects of exposure to VGs (video games) on human life and well-being. Scientific literature shows several evidences highlighting negative outcomes on behavioural, emotive, cognitive and physical health spheres. All these aspects are intrinsically linked to sleep quality and quantity and to date very few studies directly investigated the effects of videogame (VG) exposure on sleep and post-sleep cognitive status. The aim of the present systematic review is to examine the impact that the exposure to VGs can produce on sleep pattern and the consequent post-sleep cognitive abilities. To this extent, only studies directly investigating the effects of VGs on sleep features and post-sleep cognitive abilities have been selected and discussed. Data currently present in literature show the alteration of sleep pattern after exposure to VGs. The analysis indicated a reduction of Total Sleep Time (TST) and an increase of Sleep Onset Latency (SOL), modifications of the REM sleep and Slow Wave Sleep (SWS), and increased sleepiness and self-perceived fatigue. Moreover, post-sleep sustained attention and verbal memory also appear to be impaired. It can be concluded that playing VGs for long periods, particularly in the evening, is a significant, common and probable cause of sleep problems: evening exposure to VGs, in fact, can bring to insufficient and low quality sleep, with possible effects on cognition in the subsequent waking days. Potential methodological flaws and limitations of these studies have also been described and discussed. Because of the very limited number of available study on this topic further research is strongly needed.

Impact of Multi-Night Experimentally Induced Short Sleep on Adolescent Performance in a Simulated Classroom

Study Objectives

Investigate whether a realistic "dose" of shortened sleep, relative to a well-rested state, causes a decline in adolescents' learning and an increase in inattentive and sleepy behaviors in a simulated classroom setting.

Methods

Eighty-seven healthy 14.0- to 16.9-year olds underwent a 3-week sleep manipulation protocol, including two 5-night sleep manipulation conditions presented in a randomly counterbalanced within-subjects cross-over design. Wake time was held constant. Bedtimes were set to induce Short Sleep (SS; 6.5 hours in bed) versus Healthy Sleep (HS; 10 hours in bed). During the morning at the end of each condition, participants underwent a simulated classroom procedure in which they viewed lecture-based educational videotapes and completed relevant quizzes. Their behaviors in the simulated classroom were later coded by condition-blind raters for evidence of inattention and sleepiness.

Results

Adolescents had a longer average sleep period during HS (9.1 hours) than SS (6.5 hours). Compared to scores during HS, adolescents scored significantly lower on the quiz, showed more behaviors suggestive of inattention and sleepiness in the simulated classroom, and were reported by adolescents themselves and by their parents to be more inattentive and sleepy during SS. However, the impact of the manipulation on quiz scores was not mediated by changes in attention or sleepiness.

Conclusions

Although effect sizes were modest, these findings suggest that previously-reported correlations between sleep duration and academic performance reflect true cause-effect relationships. Findings add to the growing evidence that the chronically shortened sleep experienced by many adolescents on school nights adversely impacts their functioning and health.

Novel Measures to Assess the Effects of Partial Sleep Deprivation on Sensory, Working, and Permanent Memory

Sleepiness has repeatedly been demonstrated to affect performance on a variety of cognitive tasks. While the effects of total sleep deprivation (TSD) have been extensively studied, acute partial sleep deprivation (PSD), a more frequent form of sleep loss, has been studied much less often. The present study examined the effects of sleep deprivation on novel tasks involving classic sensory, working, and permanent memory systems. While the tasks did implicate different memory systems, they shared a need for effortful, sustained attention to maintain successful performance. Because of the novelty of the tasks, an initial study of the effects of TSD was carried out. The effects of PSD were subsequently examined in a second study, in which subjects were permitted only 4 h of sleep. A general detrimental effect of both total and PSD on accuracy of detection was observed and to a lesser extent, a slowing of the speed of responding on the different tasks. This overall effect is best explained by the often-reported inability to sustain attention following sleep loss. Specific effects on distinct cognitive processes were also observed, and these were more apparent following total than PSD.

The neurocognitive consequences of sleep restriction: A meta-analytic review

The current meta-analytic review evaluated the effects of experimentally manipulated sleep restriction on neurocognitive functioning. Random-effects models were employed to estimate the overall effect size and the differential effect size across cognitive domains. Age, time of day, age-adjusted sleep deficit, cumulative days of restricted sleep, sleep latency, subjective sleepiness, and biological sex were examined as potential moderators of the effect. Based on a sample of 61 studies, from 71 different populations, findings revealed a significant negative effect of sleep restriction on cognitive processing across cognitive domains (g=-0.383, p<0.001). This effect held for executive functioning (g=-0.324, p<0.001), sustained attention (g=-0.409, p<0.001), and long-term memory (g=-0.192, p=0.002). There was insufficient evidence to detect an effect within the domains of attention, multitask, impulsive decision-making or intelligence. Age group, time of day, cumulative days of restricted sleep, sleep latency, subjective sleepiness, and biological sex were all significant moderators of the overall effect. In conclusion, the current meta-analysis is the first comprehensive review to provide evidence that short-term sleep restriction significantly impairs waking neurocognitive functioning.

Are circadian rhythms new pathways to understand Autism Spectrum Disorder?

Autism Spectrum Disorder (ASD) is a frequent neurodevelopmental disorder. ASD is probably the result of intricate interactions between genes and environment altering progressively the development of brain structures and functions. Circadian rhythms are a complex intrinsic timing system composed of almost as many clocks as there are body cells. They regulate a variety of physiological and behavioral processes such as the sleep-wake rhythm. ASD is often associated with sleep disorders and low levels of melatonin. This first point raises the hypothesis that circadian rhythms could have an implication in ASD etiology. Moreover, circadian rhythms are generated by auto-regulatory genetic feedback loops, driven by transcription factors CLOCK and BMAL1, who drive transcription daily patterns of a wide number of clock-controlled genes (CCGs) in different cellular contexts across tissues. Among these, are some CCGs coding for synapses molecules associated to ASD susceptibility. Furthermore, evidence emerges about circadian rhythms control of time brain development processes.

Clock Genes and Altered Sleep-Wake Rhythms: Their Role in the Development of Psychiatric Disorders

In mammals, the circadian clocks network (central and peripheral oscillators) controls circadian rhythms and orchestrates the expression of a range of downstream genes, allowing the organism to anticipate and adapt to environmental changes. Beyond their role in circadian rhythms, several studies have highlighted that circadian clock genes may have a more widespread physiological effect on cognition, mood, and reward-related behaviors. Furthermore, single nucleotide polymorphisms in core circadian clock genes have been associated with psychiatric disorders (such as autism spectrum disorder, schizophrenia, anxiety disorders, major depressive disorder, bipolar disorder, and attention deficit hyperactivity disorder). However, the underlying mechanisms of these associations remain to be ascertained and the cause–effect relationships are not clearly established. The objective of this article is to clarify the role of clock genes and altered sleep–wake rhythms in the development of psychiatric disorders (sleep problems are often observed at early onset of psychiatric disorders). First, the molecular mechanisms of circadian rhythms are described. Then, the relationships between disrupted circadian rhythms, including sleep–wake rhythms, and psychiatric disorders are discussed. Further research may open interesting perspectives with promising avenues for early detection and therapeutic intervention in psychiatric disorders.

Chronic sleep deprivation differentially affects short and long-term operant memory in Aplysia

The induction, formation and maintenance of memory represent dynamic processes modulated by multiple factors including the circadian clock and sleep. Chronic sleep restriction has become common in modern society due to occupational and social demands. Given the impact of cognitive impairments associated with sleep deprivation, there is a vital need for a simple animal model in which to study the interactions between chronic sleep deprivation and memory. We used the marine mollusk Aplysia californica, with its simple nervous system, nocturnal sleep pattern and well-characterized learning paradigms, to assess the effects of two chronic sleep restriction paradigms on short-term (STM) and long-term (LTM) associative memory. The effects of sleep deprivation on memory were evaluated using the operant learning paradigm, learning that food is inedible, in which the animal associates a specific netted seaweed with failed swallowing attempts. We found that two nights of 6h sleep deprivation occurring during the first or last half of the night inhibited both STM and LTM. Moreover, the impairment in STM persisted for more than 24h. A milder, prolonged sleep deprivation paradigm consisting of 3 consecutive nights of 4h sleep deprivation also blocked STM, but had no effect on LTM. These experiments highlight differences in the sensitivity of STM and LTM to chronic sleep deprivation. Moreover, these results establish Aplysia as a valid model for studying the interactions between chronic sleep deprivation and associative memory paving the way for future studies delineating the mechanisms through which sleep restriction affects memory formation.

Sex-Related Differences in the Effects of Sleep Habits on Verbal and Visuospatial Working Memory

Poor sleep quality negatively affects memory performance, and working memory in particular. We investigated sleep habits related to sleep quality including sleep duration, daytime nap duration, nap frequency, and dream content recall frequency (DCRF). Declarative working memory can be subdivided into verbal working memory (VWM) and visuospatial working memory (VSWM). We hypothesized that sleep habits would have different effects on VWM and VSWM. To our knowledge, our study is the first to investigate differences between VWM and VSWM related to daytime nap duration, nap frequency, and DCRF. Furthermore, we tested the hypothesis that the effects of duration and frequency of daytime naps and DCRF on VWM and VSWM differed according to sex. We assessed 779 healthy right-handed individuals (434 males and 345 females; mean age: 20.7 ± 1.8 years) using a digit span forward and backward VWM task, a forward and backward VSWM task, and sleep habits scales. A correlation analysis was used to test the relationships between VWM capacity (VWMC) and VSWM capacity (VSWMC) scores and sleep duration, nap duration, nap frequency, and DCRF. Furthermore, multiple regression analyses were conducted to identify factors associated with VWMC and VSWMC scores and to identify sex-related differences. We found significant positive correlations between VSWMC and nap duration and DCRF, and between VWMC and sleep duration in all subjects. Furthermore, we found that working memory capacity (WMC) was positively correlated with nap duration in males and with sleep duration in females, and DCRF was positively correlated with VSWMC in females. Our finding of sex-related differences in the effects of sleep habits on WMC has not been reported previously. The associations between WMC and sleep habits differed according to sex because of differences in the underlying neural correlates of VWM and VSWM, and effectiveness of the sleep habits in males and females.

The Development of a Clinically Relevant Sleep Modification Protocol for Youth with Type 1 Diabetes

Findings from type 2 diabetes research indicate that sleep is both a predictor of onset and a correlate of disease progression. However, the role sleep plays in glucose regulation and daytime functioning in youth with type 1 diabetes mellitus (T1DM) has not been systematically investigated. Nonetheless, preliminary findings have supported that various sleep parameters are strongly correlated to health-related and neurobehavioral outcomes in youth with T1DM. This suggests that improving sleep might reduce morbidity. A critical step in developing evidence-based guidelines regarding sleep in diabetes management is to first determine that sleep modification in natural settings is possible (i.e., instructing youth to have a healthy sleep opportunity leads to more total sleep time) and that an increased sleep duration impacts disease and psychosocial outcomes in these youth. This article describes the background, design, and feasibility of an ongoing randomized clinical trial that aims to examine if increasing sleep relative to youth's own sleep routines affects glucose control and daytime functioning.

The association between social media use and sleep disturbance among young adults

INTRODUCTION

Many factors contribute to sleep disturbance among young adults. Social media (SM) use is increasing rapidly, and little is known regarding its association with sleep disturbance.

METHODS

In 2014 we assessed a nationally representative sample of 1788 U.S. young adults ages 19-32. SM volume and frequency were assessed by self-reported minutes per day spent on SM (volume) and visits per week (frequency) using items adapted from the Pew Internet Research Questionnaire. We assessed sleep disturbance using the brief Patient-Reported Outcomes Measurement Information System (PROMIS®) sleep disturbance measure. Analyses performed in Pittsburgh utilized chi-square tests and ordered logistic regression using sample weights in order to estimate effects for the total U.S.

RESULTS

In models that adjusted for all sociodemographic covariates, participants with higher SM use volume and frequency had significantly greater odds of having sleep disturbance. For example, compared with those in the lowest quartile of SM use per day, those in the highest quartile had an AOR of 1.95 (95% CI=1.37-2.79) for sleep disturbance. Similarly, compared with those in the lowest quartile of SM use frequency per week, those in the highest quartile had an AOR of 2.92 (95% CI=1.97-4.32) for sleep disturbance. All associations demonstrated a significant linear trend.

DISCUSSION

The strong association between SM use and sleep disturbance has important clinical implications for the health and well-being of young adults. Future work should aim to assess directionality and to better understand the influence of contextual factors associated with SM use.

Effects of sleep manipulation on cognitive functioning of adolescents: A systematic review

Adolescents are considered to be at risk for deteriorated cognitive functioning due to insufficient sleep. This systematic review examined the effects of experimental sleep manipulation on adolescent cognitive functioning. Sleep manipulations consisted of total or partial sleep restriction, sleep extension, and sleep improvement. Only articles written in English, with participants' mean age between 10 and 19 y, using objective sleep measures and cognitive performance as outcomes were included. Based on these criteria 16 articles were included. The results showed that the sleep manipulations were successful. Partial sleep restriction had small or no effects on adolescent cognitive functioning. Sleep deprivation studies showed decrements in the psychomotor vigilance task as most consistent finding. Sleep extension and sleep improvement contributed to improvement of working memory. Sleep directly after learning improved memory consolidation. Due to the great diversity of tests and lack of coherent results, decisive conclusions could not be drawn about which domains in particular were influenced by sleep manipulation. Small number of participants, not accounting for the role of sleep quality, individual differences in sleep need, compensatory mechanisms in adolescent sleep and cognitive functioning, and the impurity problem of cognitive tests might explain the absence of more distinct results.

Effects of sleep reduction on the phonological and visuospatial components of working memory

Sleep reduction impairs the performance of many tasks, so it may affect a basic cognitive process, such as working memory, crucial for the execution of a broad range of activities. Working memory has two storage components: a phonological and a visuospatial component. The objective of this study was to analyze the effects of sleep reduction for 5 days on the storage components of working memory. Thirteen undergraduate students (18.77±2.20 years of age), 5 men and 8 women, responded two N-Back tasks (auditory and visual), with three sections each (0-Back, 1-Back, and 2-Back). These tasks were performed at 13:00 h under the following conditions: before sleep reduction (control; C); on the first (SR1), fourth (SR4), and fifth (SR5) days of sleep reduction (4 h of sleep per night); and one day after they slept freely (recovery, R). Sleep reduction produced a decrement in accuracy on the auditory 2-Back section the fifth day of sleep reduction (C=87.86±13.35%; SR5=74.76±16.37%; F=14.57, p<0.01). In the visual 2-Back section accuracy decreased (C=88.10±9.95%; SR1=82.45±11.57%; SR5=77.76±14.14%; F=10.80, p<0.05), and reaction time increased (C=810.02±173.96 ms; SR1=913.51±172.25 ms; SR5=874.78±172.27 ms; F=10.80, p<0.05) on the first and fifth day of sleep reduction. In conclusion, five days of sleep reduction produces a decrease in the phonological and visuospatial storage components of working memory, which may interfere with processing verbal information and solving problems that require spatial analysis.