bluuebunny/crossref_metadata_2025_split huggingface dataset:
0334 Hippocampal Development, Slow Wave Activity, and Nap-Dependent Memory Consolidation in Early Childhood
Authors: Lokhandwala S , Allard T , Riggins T , Spencer R M 
Published: May 2020

Abstract

Introduction
Naps support memory consolidation in early childhood. In adults, nap-dependent declarative consolidation is associated with SWA. SWA increases from early childhood into adulthood, and the shift of SWA from occipital to frontal distribution (F/O-ratio) is a marker of brain maturation. Thus, we explored how electrophysiological and structural characteristics of brain development relate to nap-dependent declarative learning in early childhood.

Methods
Twelve preschool-age children (8 female, M=48 months, SD=0.44) have completed three sessions (~1wk apart) within a larger study. In the first two sessions, children completed a visuo-spatial task before and after a 2-hr nap or wake interval. During the third visit, children underwent MRI assessment. Using PSG, SWA was measured in the delta band over frontal and occipital regions for nREM2 and nREM3 sleep.

Results
While F/O-ratio of SWA does not currently predict the F/O-ratio of cortical thickness (r(12)=.383, p=.219), right parahippocampal thickness positively correlates with F/O-ratio of SWA in nREM2 (r(12)=.591, p=.043). Nonetheless, children’s performance change following the nap was not associated with either parahippocampal thickness or F/O-ratio of SWA in any sleep stage (all ps&gt;.538). However, performance in children who showed a post-nap benefit (n=5) positively correlated with right parahippocampal thickness (r(5)=.915, p=.029). This was not the case for children who did not show a post-nap benefit (r(7)=-.199, p=.668).

Conclusion
Although the F/O-ratio of SWA did not predict a similar ratio of cortical thickness, the association between right parahippocampal thickness and F/O-ratio of SWA is evidence that development of SWA parallels cortical development. While there is no overall association between post-nap performance and brain development characteristics, the relation between performance and right parahippocampal thickness in children showing a nap benefit suggests that memory during this age may depend on structural (rather than electrophysiological) brain development changes.

Support
NIH R21 HD094758 & NSF BCS 1749280
0340 Regional Changes in Sleep Electroencephalography Power in Youth with Sleep-Disordered Breathing: A High-Density EEG Study
Authors: Myers A , Matthews C , Kille T , Riedner B , Flaherty B , Jones S 
Published: May 2020

Abstract

Introduction
Daytime neurobehavioral impairments are commonly associated with sleep disordered breathing (SDB) in children. However, a large number of studies have shown only minimal differences in sleep between children with SDB relative to control children, suggesting that sleep dysfunction is not responsible for daytime impairment. Importantly, however, previous studies have measured sleep EEG using only frontal scalp electrodes, failing to capture the regional features of sleep that are prominent during development. Here we measure sleep using hdEEG in SDB and healthy children to determine if regional sleep impairment is related to daytime neurobehavioral performance.

Methods
Overnight high-density electroencephalography (hdEEG, 256 channels) was recorded in 17 children with sleep disordered breathing (SDB) (age: M = 8.46, SD = 1.82, AHI: M = 11.3, SD = 8.6, 53% female) and 17 age and sex matched controls (age: M = 8.47, SD = 1.66, AHI: M = 1.5, SD = .64). Attentional capacity was assessed using the Test of Variables of Attention (TOVA) before and after sleep. Group differences in sleep macrostructure variables were assessed using unpaired t-tests. All-night spectral analysis was performed for NREM sleep and averaged across groups. Topographic differences between groups were assessed using statistical non-parametric mapping. Pearson correlations were used to determine associations between sleep and TOVA variables.

Results
Sleep macrostructure did not differ between groups. All-night spectral density analysis revealed a global increase in high-frequency activity in N2N3 and N3, in the alpha band (8-12 Hz, p&lt;0.05). Global alpha power was higher in SDB youth, although this effect reached significance during N3 in a large cluster of posterior channels (N=55, p=.02).

Conclusion
Elevated alpha during NREM is frequently considered a correlate of nonrestorative sleep. In this sample of youth with SDB, posterior alpha is robustly increased during the deepest stage of NREM sleep. In this small sample, however, alpha power did not predict performance on an attentional task sensitive to the effects of impaired sleep.

Support
R21 HD092986-02 to SJ
0341 Preliminary Effects of a Music Intervention on Actigraphy-Measured Sleep Among Older Adults with Dementia
Authors: Mu C , Lee S , Risal P G , Vigoureux T F , Bugos J , Meng H 
Published: May 2020

Abstract

Introduction
Music may benefit sleep and daytime alertness by decreasing stress, increasing attention, and potentially, slowing the progression of dementia. This study examined preliminary effects of a group-based music intervention on sleep health among older adults with dementia.

Methods
Participants were older adults with dementia living in an assisted living facility (n=9; Mage=80.11; Mrange=63−89 years). Cohort 1 (n=4) received the intervention in the morning and cohort 2 (n=5) received the intervention in the afternoon. Participants completed a 4-week intervention protocol (12 sessions) along with a one-week actigraphy sleep assessment before and after the intervention. Informed by sleep literature, we constructed a composite sleep health score encompassing Regularity, Satisfaction or quality, Alertness, Timing, Efficiency, and Duration (higher scores indicating more daily sleep problems). Using descriptive statistics and multilevel modeling, we evaluated preliminary effects of the intervention on overall sleep health and each of the sleep dimensions.

Results
Six out of nine participants exhibited a decrease in overall sleep problems at post-intervention. All 4 participants in cohort 1 showed improvement in overall sleep health at post-intervention. Specifically, in cohort 1, participants exhibited a decline in nightly sleep problems, decreased daytime nap duration, and number of naps. In contrast, while two out of five participants in cohort 2 exhibited improvement in overall sleep health, the remainder of the participants exhibited no improvement in daily sleep problems, especially in nap domains. Across cohorts, those younger in age, with vascular dementia, lower weight, and not taking sleep or hypertension related medications tended to respond better to the intervention.

Conclusion
Our preliminary results demonstrate the feasibility and potential benefit of a group-based music intervention in improving overall sleep health among older patients with dementia. Implications for conducting community-based non-pharmacological interventions to improve sleep and daytime functioning among older adults with dementia will be discussed.

Support
This work was supported, in part, by the Florida Department of Health Ed and Ethel Moore Alzheimer’s Disease Research Award (PI: Meng, Grant #9AZ28).
0350 Characterizing Continuous Changes in Spectral Dynamics of Sleep EEG as a Function of Age
Authors: Kim H , Prerau M , Redline S 
Published: May 2020

Abstract

Introduction
Sleep is a continuous and dynamic physiological process. Current research practice, however, limits our ability to observe electroencephalography (EEG) oscillation dynamics by breaking sleep into discrete stages. In this study, we propose a novel quantitative framework that represents population-level changes in sleep EEG spectral dynamics as a function of age, preserving the information-rich spectral dynamics of sleep data. Rather than relying on sleep stages, our approach uses slow-oscillation power (SO-power) as an objective, continuous-valued correlate of sleep depth.

Methods
We analyzed the EEG signal (Fz-Cz, 256 Hz sampling rate) from a subset of the Multi-Ethnic Study of Atherosclerosis (MESA) study participants (n = 2056, 53.6% female, age: mean 69.37 ± 9.12, range 54 - 94) who underwent polysomnography. For each subject, we computed the sleep EEG multitaper spectrogram and extracted the total baseline-normalized SO-power (0.1 - 1.5 Hz). We next computed mean EEG spectral power as a function of SO-power, which we then tracked across all subjects as a function of age in sliding windows.

Results
The population analysis shows apparent, continuous changes in time-frequency domain features of the EEG as a function of a sleep depth along with age, that would be otherwise lost in traditional analyses. Moreover, by analyzing the directionality of the SO-power, we show that there is no apparent difference in neural activity during deepening sleep and lightening sleep; thus EEG sleep state is likely non-directional.

Conclusion
Our results show that state-based sleep dynamics of the EEG power spectrum can comprehensively be represented using SO-power as a surrogate of sleep depth. This representation identifies state-based activity independent of the temporal evolution of sleep architecture. As such, it is a powerful tool for analysis and phenotyping of EEG activity in large cohorts.

Support
The Biomedical Global Talent Nurturing Program through the Korea Health Industry Development Institute, funded by the Ministry of Health & Welfare, Republic of Korea (HI19C1065) to HK, National Institute of Neurological Disorders and Stroke (NINDS, R01 NS-096177) to MP.
0352 A Large-Scale EEG Study at Home to Objectivise Effects of Ageing on Slow Wave Sleep and Process S
Authors: El Kanbi K , Thorey V , Artemis L , Chouraki A , Trichet T , Pinaud C , Debellemaniere E , Arnal P J 
Published: May 2020

Abstract

Introduction
Several studies have shown slow wave sleep (SWS) is altered with ageing. However, most of these studies have been conducted in-lab and usually over a single night. In this study, we assessed the evolution of process S with ageing by analysing the dynamics of endogenous and auditory-evoked slow waves in a large population.

Methods
300 participants (200 M, 20 - 70 y.o.) were selected from volunteers users wearing a sleep headband for at least 3 nights, meeting the criteria of high signal quality and having no subjective sleep complaints nor being shift-workers. The Dreem headband is a connected device able to monitor EEG signals as well as pulse and movement and performs sleep staging in real-time automatically. Slow waves were detected as large negative deflections on the filtered EEG signals during NREM sleep. The auditory evoked slow waves were done using a previously validated closed-loop procedure.

Results
In our study, age was strongly correlated with N3 sleep duration (r=-0.34, p&lt;0.0001), slow wave amplitude (r=-0.25, p&lt;0.0001), and slow wave density (r=-0.40, p&lt;0.0001). The slope of the slow wave activity, representing the process S here, was significantly decreased (r=-0.32, p&lt;0.0001). This effect was mainly due to changes in the density of slow waves in the first 2 hours of sleep (r=-0.41, p&lt;0.0001). Finally, our results show a decrease in the probability of auditory evoked slow waves (r=-0.43, p&lt;0.0001).

Conclusion
These results confirmed the in-lab studies showing a heterogeneous alteration of homoeostatic process S with age, as well as a general decrease of slow wave occurrences, that is observed in parallel of a decrease of the probability of evoking slow waves, suggesting a global change in the system responsible for slow wave generation.

Support
This study was supported by Dreem sas and ANR, FLAG ERA 2015, HPB SLOW-Dyn
0360 Neighborhood Disadvantage is Associated with Lower Quality Sleep and More Variability in Weeknight Sleep Duration Among Urban Adolescents
Authors: Nahmod N G , Master L , McClintock H F , Hale L , Buxton O M 
Published: May 2020

Abstract

Introduction
Differential social and contextual environments may contribute to adolescent sleep disparities. Yet, most prior studies are limited to self-reported sleep data, and the actigraphic studies of sleep are not conducted at a national level, thus limiting the variation in neighborhood contexts. This study examined the association between neighborhood disadvantage and actigraphic assessment of adolescent sleep.

Methods
Participants (682 adolescents, mean age 15.4 years) were racially/ethnically diverse (44% Black, 26% Hispanic, 17% White, 14% other race/ethnicity), sampled from 20 large US cities in the Fragile Families and Child Wellbeing Study. Neighborhood disadvantage was calculated from American Community Survey 2015 census data using the Standardized Neighborhood Deprivation Index (SNDI), consolidating five variables (proportion of female-headed households, public assistance recipients, households in poverty, adults without high school degrees, and unemployed) into an index. SNDI quartiles 1-3 fell below national averages of SNDI variables (“most disadvantaged”) and were compared to quartile 4 (“least disadvantaged”). Sleep indicators (duration, quality, and timing) were measured over ≥5 nights using wrist-worn accelerometers. Separate multilevel models estimated differences in sleep indicators, adjusting for weekday/weekend and summer/school year. General linear models used within-person standard deviations of sleep indicators (controlling for number of days) to test for associations between neighborhood disadvantage and consistency of weeknight sleep patterns. Models adjusted for individual-level sociodemographic covariates (age, sex, race/ethnicity, household income, caregiver education, and family structure).

Results
In fully adjusted models, adolescents living in more disadvantaged neighborhoods spent more time awake after falling asleep (4.0 minutes/night, p&lt;0.05), spent greater percentage of nighttime sleep intervals awake (1%, p&lt;.01), and had less consistent sleep duration (11.7% higher standard deviation, p&lt;.05). Sleep duration and timing did not differ across neighborhood groups.

Conclusion
Living in more disadvantaged neighborhoods is associated with lower quality adolescent sleep; more research is needed to identify causal mechanisms.

Support
Research was supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) of the National Institutes of Health (NIH), award numbers R01HD073352 (PI: Hale), R01HD36916, R01HD39135, and R01 HD40421, and private foundations. The content is the responsibility of the authors and does not represent official NIH views.
0379 Green Space Exposure and Sleep Duration Among Supplemental Nutrition Assistance Program Participants
Authors: Grigsby-Toussaint D , Shin J 
Published: May 2020

Abstract

Introduction
Emerging empirical evidence suggests green space exposure is protective against insufficient sleep. Limited studies exist, however, exploring the relationship between greenspace exposure and sleep among low income populations in the United States.

Methods
Using a sample of Supplemental Nutrition Assistance Program (SNAP) participants (n=104) recruited from Champaign County, Illinois, we examined the relationship between self-reported sleep duration and exposure to green space. Sleep duration was determined using the question, “On average, how many hours did you sleep each night during the past 4 weeks?” Green space exposure was determined using satellite imagery from the National Aeronautic Space Administration (NASA) normalized difference vegetation index (NDVI). An NDVI score was assigned to each participant based on residential geo-referenced data. Multiple linear regression was performed in SPSS to explore the relationship between self-reported sleep duration and green space.

Results
Higher number of hours of sleep within a 24-hour period was positively associated with higher scores for greenspace exposure (β=0.091, P=0.02), controlling for age, gender, smoking status, education, alcohol consumption, and sleep quality. Sleep duration was negatively associated with age (β=-0.03, P=0.007), but positively associated with sleep quality (β=0.856, P=0.008).

Conclusion
In a sample of SNAP participants, exposure to green space was associated with more hours of sleep per night. Additional studies with larger, and more geographically diverse samples of low income adults are needed to determine whether this relationship is robust.

Support
USDA UNC/DUKE BECR Center
0384 Do Nurses with High Blood Pressure Have More Sleep Disturbances Than Their Peers?
Authors: Santiago B P , Messman B A , Slavish D C , Alkire C , Wardle-Pinkston S , Dietch J R , Kelly K , Ruggero C R , Taylor D J 
Published: May 2020

Abstract

Introduction
Nurses work in stressful environments and often have rotating work schedules, which may put them at risk for disturbed sleep and health. Poor quality and short sleep duration are strong risk factors for high blood pressure (HBP). Yet few studies have examined these associations in nurses, who may be a particularly at-risk sample. To address this gap, we examined group differences in self-reported and actigraphy-assessed sleep among nurses with and without self-reported HBP.

Methods
Participants were 392 nurses (91.8% female; 77.8% white, mean age = 39.54) recruited for a parent study. Participants completed baseline questionnaires including the Pittsburgh Sleep Quality Index (PSQI), followed by 14 days of actigraphy and sleep diaries to prospectively assess 14-day mean total sleep time (TST) and sleep efficiency (SE). An independent samples t-tests was used to assess group differences in sleep variables by HBP status. Linear regression was used to further examine the association between HBP status on sleep variables when controlling for age, race, gender, ethnicity, and body mass index (BMI).

Results
Twenty-nine (7%) nurses endorsed having clinically-diagnosed HBP. Nurses with HBP had higher global PSQI scores (indicating worse sleep quality; t=2.71, p=0.007), compared to nurses who did not report HBP, with a mean difference of 1.24. When adjusting for covariates, the association between HBP and the PSQI became marginally significant (p=0.054). There were no group differences in sleep diary or actigraphy TST or SE by HBP status, nor did HBP predict these sleep variables when controlling for covariates.

Conclusion
We found that nurses who reported having clinically diagnosed HBP had poorer global sleep quality. Although limited by self-reported history of HBP diagnosis, and low endorsement of HBP in our sample, our results corroborate other findings which suggest there is a strong association between high blood pressure and disturbed sleep. Future studies should examine these associations in larger samples, assess blood pressure directly, and experimentally examine the effects of HBP treatment on sleep quality.

Support
NIH/NIAID R01AI128359-01
0398 Demographic Differences in the Degree of Discrepancy Between Sleep Diary and Actigraphy Measures of Sleep
Authors: Scott B , Crawford M , Slavish D , Messman B , Wardle-Pinkston S , Dietch J , Kelly K , Ruggero C , Taylor D 
Published: May 2020

Abstract

Introduction
The accurate estimation of sleep is critical for understanding who is most at risk for sleep disorders and associated disease outcomes. Individuals who overestimate sleep disturbances may be at increased risk for insomnia. A few studies have shown demographic differences in the accuracy of sleep estimation when comparing subjective and objective measures; however, the previous literature is inconsistent and focuses primarily on older adults. We sought to replicate these studies in a large sample of nurses using 14 days of sleep diary and actigraphy measures.

Methods
Participants were 392 nurses (91.8% female; 77.8% white, mean age = 39.54) recruited for a larger study. Participants completed 14 days of actigraphy and sleep diaries to prospectively assess total sleep time (TST) and sleep efficiency (SE). Discrepancy between diary and actigraphy measures was calculated by subtracting actigraphy measures from diary measures. Linear regression was used to examine how age, race (0 = race other than white, 1 = white), gender (1 = male, 2 = female), ethnicity (1= non-Hispanic/Latinx, 2 = Hispanic/Latinx) predicted degree of sleep discrepancy.

Results
The average discrepancy between diary and actigraphy TST was 30.29 minutes (SD = 29.28), and the average discrepancy between diary and actigraphy SE was 4.16% (SD = 5.66). Race and ethnicity did not predict amount of TST or SE discrepancy. However, younger individuals had more discrepancy in both TST (b = -0.48, p &lt; .001) and SE (b = -0.09, p &lt; .001). Men also had a greater discrepancy in both TST (b = -10.90, p &lt; .05) and SE (b = -2.56, p &lt; .05).

Conclusion
Men and younger individuals had greater discrepancies between diary and actigraphy measures of sleep. This is in contrast to some previous research showing that elderly women tend to display greater discrepancies between subjective and objective measures of sleep. It is essential that future research explore the discrepancies between subjective and objective measures of sleep in larger and more demographically diverse samples. Establishing a better understanding of this relationship is crucial, as it may have significant implications for the diagnosis and treatment of insomnia.

Support
NIH/NIAID R01AI128359-01
0400 Habitual Sleep, Circadian Misalignment, and Cardiovascular Risk Factors Among Late Adolescents
Authors: Ji X , Wang Y , Saylor J , Patterson F , Ruggiero L 
Published: May 2020

Abstract

Introduction
Emerging evidence suggests the potential role of sleep in cardiovascular disease (CVD) risk. Sleep variability and circadian misalignment may represent understudied sleep dimensions, particularly among late adolescents. This study investigated the associations of habitual sleep, circadian misalignment, night-to-night sleep variability with CVD risk factors among late adolescents.

Methods
Using a cross-sectional design, we enrolled 58 healthy, college students (19.22±1.06 years old). Participants completed a 7-day sleep diary, the Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale. Circadian misalignment was assessed using the weekend-weekday differences in sleep duration and midsleep time. Sleep variability was calculated as intra-individual standard deviation of sleep durations. The number of CVD risk factors (BMI, waist circumference, blood pressure, fasting glucose and lipid profile) above subclinical/clinical thresholds was used as a proxy of overall risk. Logistic and generalized linear regression tested the relationships.

Results
Forty-two participants (73%) had at least one elevated CVD risk factors and 19 (34%) were short sleepers (&lt;7 h). On average, the midsleep shifted 54 minutes later on weekends and the intraindividual sleep variability was 1.31 hours. After controlling for age, gender and race, there was a trend towards higher overall CVD risk (β=0.45±0.22, p=0.05) with a greater weekend-weekday discrepancy in sleep duration. For each CVD risk factor, a greater discrepancy in weekend-weekday midsleep times (OR=2.29±0.82, p=0.02) was estimated to increase the odds of high blood pressure. Participants with greater discrepancy in weekday-weekend sleep durations (OR=1.58±0.41, p=0.03) or excessive daytime sleepiness (OR=4.68±3.38, p=0.03) were more likely to have high BMI. Worse sleep quality (higher PSQI scores) was associated with high BMI (OR=1.36±0.19, p=0.03) and waist circumference (OR=1.40±0.24, p=0.04).

Conclusion
This study suggests that circadian misalignment, compared with other sleep characteristics, better predicts cardiovascular risk among late adolescents. Future research is needed to examine the interaction among circadian misalignment, sleep variability and sleep duration on CVD risk.

Support
American Nurse Foundation 18A01422