bluuebunny/crossref_metadata_2025 huggingface dataset:
0039 An Apple a Day Keeps Bad Sleep Away? Carotenoid Consumption and Multimodal Sleep Outcomes in Adolescents
Authors: Kamhout Sarah , Duraccio Kara
Published: April 2024

Introduction

Carotenoid consumption has been linked with greater likelihood of appropriate sleep duration and higher levels of sleep quality in adults. As only 2-7% of American adolescents met recommended fruit and vegetable intake guidelines in 2017, and over 70% of high schoolers regularly sleep less than 8 hours per night, adolescents may be especially influenced by relationships between poor diet and poor sleep. Previous studies in this area have been limited to other age groups or examination of singular sleep constructs.

Methods

Seventy-four adolescents (14-18 years; 43 female) completed 2-3 ASA-24 dietary recalls across randomized weekend and weekdays. They also completed the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD), and a Dim-Light Melatonin Onset (DLMO) appointment. Bivariate regressions examined potential associations between average carotenoid consumption (α Carotene, β Carotene, β Cryptoxanthin, Lycopene, Leutin + Zeaxanthin) and self-reported sleep duration (PSQI Item 4), daytime sleepiness (ESS-CHAD Total) and melatonin onset time (DLMO, threshold 4 pg/mL). Subject age and sex were controlled for within each model. To correct for multiple comparisons, p was set to a significance threshold of 0.01 for predictors within the model and 0.05 for the entire model.

Results: Results

β Cryptoxanthin was a significant predictor of daytime sleepiness (beta=-.024, t(72)=-2.682, p=.009) and explained significant variance in the comprehensive model for this outcome (R2 = .072, F(3, 69)=2.901, p=.041). No other carotenoids emerged as significant predictors of sleep outcomes after correction for multiple comparisons. β Carotene neared significance for predicting duration (beta=-.258 , t(72)=-2.22, p=.030; R2 = .033, F(3, 69)=1.829, p=.15), as did Lycopene (beta=.243 , t(72)=2.086, p=.041; R2 = .026, F(3, 69)=1.632, p=.19).

Conclusion

β Cryptoxanthin could be investigated as a potential influence on daytime sleepiness in this age group. Further studies are needed to establish causality and to examine the clinical significance of consumption increases in this age group. Underconsumption of whole foods common to this developmental period may make it difficult to detect the effects of adequate or increased intake cross-sectionally.

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0042 Melanopsin Crispants in Zebrafish Display Difference in Sleep Latency
Authors: Doldur-Balli Fusun , Smieszek Sandra , Veatch Olivia , Keenan Brendan , Zimmerman Amber , Polymeropoulos Christos , Birznieks Gunther , Polymeropoulos Mihael
Published: April 2024

Introduction

Melanopsin (OPN4) is a blue light sensitive opsin type G protein couple receptor. It is highly expressed in the photsenstive ganglion cells which mediate responses to light including regulation of sleep, circadian photoentrainment and pupillary light responses. Mutations in OPN4 were shown to affect responses to light ultimately affecting the regulation of circadian rhythms and sleep patterns. Sleep homeostasis was altered in homozygous knockout of Opn4, gene encoding for melanopsin, in mice. Human melanopsin variants which alter function significantly may contribute to sleep disturbance, circadian dysfunction and visual impairment. In order to further dissect the role of melanopsin in sleep in a diurnal vertebrate model, we created an F0 knockout model of opn4 gene in zebrafish and assessed sleep/wake phenotype.

Methods

In CRISPR/Cas9 screening, single cell-stage zebrafish embryos were injected with injection cocktail containing Cas9 protein and crRNAs targeting opn4a and opn4b, homologous genes of human OPN4. Control groups were negative control crRNA injected embryos. Zebrafish larvae were individually pipetted into each well of a 96 well plate. Larval zebrafish were raised on a 14 hour/10 hour light/dark cycle at 28.5◻C until sleep phenotyping starts. Sleep phenotyping was carried out between days 5-8 post injection.

Results

Longer sleep latency at night was observed in opn4 CRISPR knockout larvae. This is in line with prior literature. Additional tests by exposing opn4 crispants and control zebrafish larvae to white light and dark pulses at different times were performed however the activity and sleep latency did not change across groups.

Conclusion

Sleep/wake phenotyping of opn4 (melanopsin) crispants in zebrafish displayed significant difference in sleep latency parameter compared to controls. Although additional tests carried out using pulses of white light need to be repeated, current results highlight the importance of OPN4 mediated pathways in affecting sleep latency.

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0048 Investigating the Effects of Consecutive Nights of Pre-sleep Alcohol Use on Sleep Spindle Density and Distribution
Authors: McCullar Katie , Barker David , McGeary John , Gredvig-Ardito Caroline , Saletin Jared , Carskadon Mary
Published: April 2024

Introduction

We previously reported the impact of consecutive nights of alcohol on sleep macrostructure variables. Sleep spindle density and distribution, however, remain unexamined in response to alcohol. This report tests the hypothesis that sleep spindle density will be lower following pre-sleep alcohol and most affected early in the sleep period.

Methods

Thirty (15F; ages=22-57, mean=33) healthy adult participants took part in a crossover, within-subjects study with two 3-night in-lab conditions: a Mixer + Alcohol condition targeted a BrAC of 0.08 mg/L and a counter-balanced Mixer-only condition; conditions were separated by ≥ 3 days. All drinking ended 1 hour before lights out. Sleep EEG derivations C3-A2 and C4-A1 were submitted to a validated sleep spindle detection algorithm (Ferrarelli, et al., 2007). Sleep spindle density in NREM sleep (#/min; Stages 2-4) was averaged between channels and submitted to a series of linear mixed-effects models. A first, 2x3 model examined the factors beverage and night (Nights 1-3) on NREM spindle density. Next, data were stratified into thirds of the night, with the model repeated for each third.

Results

A main effect of alcohol on sleep spindle density across the whole night was identified (F(1,145)=5.33, p=.022). Sleep spindle density was lower on Mixer + Alcohol nights (1.6±0.7 spindles/min) vs Mixer-only (1.9±0.5 spindles/min). No effect of Night(1-3) or interaction of beverage and night was observed (p’s>.05). Next, we identified opposing effects of alcohol on sleep spindle density in early vs. late sleep. In the first third of the night sleep spindle density was lower on Mixer + Alcohol nights (0.4±0.3 spindles/min) compared to Mixer-only (0.9 ± 0.3 spindles/min; F(1,145)=8.33, p<.01)). In the final third of the night, spindle density was conversely higher in the Mixer + Alcohol nights (2.9±1.1 spindles/min) compared to Mixer-only (2.1±0.8 spindles/min; F(1,145)=4.1, p=.03)). No other effects were identified (p’s>.05).

Conclusion

Alcohol use prior to sleep resulted in reduced sleep spindle density early in the night and higher spindle density late in the night. No effects of consecutive nights were observed. These differences add to a growing discussion of the impact that alcohol has on sleep physiology across the night.

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R01AA025593
0049 Sleep and Electroencephalogram Effects from a Dual Orexin Receptor Antagonist in Mice with Traumatic Brain Injury
Authors: Craig John , Carey Sean , Gibbons Allison , Kaplan Gary , Zielinski Mark
Published: April 2024

Introduction

Traumatic brain injuries (TBI) can cause persistent sleep dysregulation regardless of injury severity including hypersomnia, hyposmia, sleepiness, sleep fragmentation, and altered electroencephalogram (EEG) power spectra. Most TBIs are mild in severity, occur in the frontal cortex, and sleep dysregulation can change over time. Orexin targets two receptors that stimulate monoamine release in the brain to promote wakefulness. Our goal was to determine if a dual orexin receptor antagonist (DORA) could improve sleep dysregulation in mice with TBI.

Methods

Two-month-old male and female C57BL/6J mice were randomly assigned to treatment groups. Mice underwent polysomnography surgery. After recovery, mice were administered vehicle by gavage then underwent baseline sleep recordings for 24 h followed by a multiple sleep latency test (MSLT). Mice received a craniectomy and mild/moderate TBI via controlled cortical impact or only a craniectomy serving as a control. A DORA or vehicle were given by gavage, and sleep and MSLT were recorded 24 h, 2 wks, 1 m, and 2 m post-TBI. Sleep state amounts and episode durations and frequencies, sleep latency, and EEG power spectra (0-40 Hz) were determined with significance set at p< 0.05.

Results

In mice given the DORA or vehicle, non-rapid-eye movement (NREM) sleep was significantly increased 24 h after TBI compared to controls. Conversely, NREM sleep was significantly reduced 2 m post-TBI in both vehicle and DORA groups. DORA and/or TBI groups had significantly reduced waking episodes 24 h post-injury but increased waking episodes 2 m post-TBI compared to controls indicating sleep fragmentation. Largely, significantly increased sleep latency time in the MSLT was found throughout all times post-injury in the DORA and TBI groups compared to the controls, which suggests increased sleepiness. Relative to controls, TBI significantly increased EEG delta power (0.5-4 Hz) 24 h post-TBI and significantly reduced EEG delta power 2 m post-TBI, although other frequency bands were not affected.

Conclusion

These data suggest that a DORA induces sleepiness but has minimal effects on impaired sleep amounts, sleep fragmentation, sleepiness, and EEG power spectra 2 m after mild/moderate TBI.

Support (if any)

Merit Review Award (I01BX005379)(MRZ) and SPiRE Award (I21RX003722)(GBK) Department of Veterans Affairs
0052 Recovery Nap After Total Sleep Deprivation Restores Emotional Memory Performance to Typically-Rested Levels
Authors: Cunningham Tony , Denis Dan , Bottary Ryan , Kensinger Elizabeth , Zeng Shengzi , Stickgold Robert
Published: April 2024

Introduction

While a brief period of recovery sleep can ameliorate the negative impacts of total sleep deprivation (TSD) on cognitive functioning, the effects of post-TSD recovery sleep on different forms of emotional functioning remain equivocal. Here, we investigated the effects of TSD and post-TSD recovery sleep on emotional memory processing and compared it to typical functioning in a rested condition.

Methods

During encoding of the emotional memory trade-off (ETO) task, participants viewed scenes with negative or neutral central objects overlaid on neutral backgrounds. During recognition, the central objects and backgrounds were presented separately and participants were asked to identify each of them as ‘Old’ or ‘New’. Forty-six participants in the TSD condition and 22 participants in the Sleep condition completed encoding the morning after the sleep manipulation (~10:00) and a recognition test was conducted on half of the scene components after a short delay (Recog_1, ~10:45). Twenty of the TSD participants were then given a 90-min nap opportunity (TSD_Nap). Participants then completed a second recognition test on the remaining images (Recog_2, ~14:00).

Results

At Recog_1, a group effect revealed significantly worse memory after TSD compared to Sleep (p=.02). Specifically, memory was significantly worse for every scene component except neutral objects, and there were no baseline differences between TSD_nap and TSD_NoNap participants. At Recog_2, memory continued to deteriorate for all scene components in the TSD_NoNap group compared to their Recog_1 performance (all p’s< 0.025). The TSD_nap group, however, had no change in memory for any of the neutral scene components and had improved negative object memory (p=.049) driven by a reduced false alarm rate (p<.001). As such, performance in the TSD_nap group matched the Sleep group at Recog_2 (all p’s>0.1).

Conclusion

These results demonstrate that post-TSD recovery sleep preserves and restores memory functioning such that performance matches typically-rested individuals – while extended TSD leads to continued deterioration – highlighting the importance of sleep in healthy emotional memory functioning. Additionally, the ETO effect (i.e., greater disparity between negative objects and their paired backgrounds compared to neutral objects and their backgrounds) was preserved for both recognition tasks in all groups, demonstrating the strength of this memory phenomenon.

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0054 PTSD Severity Moderates the Association Between N3 Nested Sleep Spindles and Emotional Memory
Authors: Richards Anne , Natraj Nikhilesh , Santistevan Anthony , Yack Leslie , Woodward Steven , Mathalon Daniel , Neylan Thomas
Published: April 2024

Introduction

Sleep disturbance is a core feature of posttraumatic stress disorder (PTSD) and may contribute to aberrant emotional memory processing in the disorder. Sleep spindles during N3 sleep that overlap temporally with slow oscillations (nested N3 SO spindles) are thought to play a role in memory consolidation and may be one mechanism through which adaptive memory processes are disrupted in PTSD.

Methods

N = 44 trauma-exposed participants (Mean Age = 32.4 (SD = 6.0), 47.7% female, 86.4% veteran) with variable PTSD severity (Mean CAPS-5 = 15.5 (SD = 10.8)) based on clinician-administered PTSD Scale (CAPS-5) viewed emotional and neutral International Affective Picture Scale (IAPS) images during electroencephalography (EEG) recording. Neurophysiological reactivity in the 300-1000 msec following stimulus presentation (late positive potential (LPP)) was measured. Participants then took a polysomnography (PSG) measured nap from which nested N3 SO spindle rates were derived. Participants’ recall memory of images was assessed post nap. Linear regression was used to test for an interaction between CAPS score and LPP magnitude (emotional minus neutral) in predicting N3 SO spindle rate and to test for an interaction between CAPS score and N3 SO spindle rate in predicting emotional memory measures (emotional hit rate, false alarm rate, and d', controlling for neutral).

Results

Across subjects, the LPP was greater for emotional compared to neutral images (p < 0.001). Furthermore, the association between LPP magnitude and nested N3 SO spindles was moderated by CAPS severity (p = 0.03), such that participants with low CAPS evidenced a positive association between LPP reactivity and nested N3 SO spindle rate (p = 0.048) whereas high CAPS participants showed no association (p = 0.26). We additionally found that associations between nested N3 SO spindle rate and several measures of emotional memory were moderated by CAPS severity (ps < 0.05): higher nested N3 SO spindle rates were correlated with worse memory for emotional images in high CAPS participants (ps < 0.05), but improved memory in low CAPS participants (ps < 0.05).

Conclusion

Results suggest a breakdown in the function of nested N3 SO spindles for emotional memory consolidation in PTSD.

Support (if any)

VA Career Development Award 5IK2CX000871-05 (PI Richards) .
0055 Leptin Moderates the Relationship Between Sleep Quality and Memory Function: A Population-based Study
Authors: Mosini Amanda , Adami Luana , Vallim Julia , Moyses-Oliveira Mariana , Poyares Dalva , Andersen Monica , Tufik Sergio
Published: April 2024

Introduction

Sleep is crucial for memory, as it promotes its encoding, consolidation, storage, and retrieval. Sleep periods following learning enhance memory consolidation. Leptin, a hormone that regulates appetite and energy balance, also influences memory and neuroplasticity. It plays a neurotrophic role in the hippocampus, enhancing synaptic function and promoting memory processes. Given these associations between sleep, memory, and leptin, this study aimed to evaluate the interplay between sleep quality, memory complaints and leptin levels.

Methods

Using data from the São Paulo Epidemiologic Sleep Study (EPISONO) 2007 edition, we analyzed data from 881 participants who underwent evaluations for subjective sleep quality (Pittsburgh Sleep Quality Index), memory function (Prospective and Retrospective Memory Questionnaire), body mass index and plasmatic leptin levels. Linear regression explored variable relationships, and a mediation/moderation model assessed causal effects on sleep quality, memory, and leptin, with age as a covariate. Analyses were performed on all volunteers and separately by sleep quality, considering sex as a potential influence. The statistical software used was Jamovi version 2.3.24, with a significance level set at 5% (p< 0.05).

Results

After confirming that subjects with poor sleep quality had more memory complaints (p< 0.001) in our cohort, we observed that leptin levels were increased in individuals with more memory complaints (p< 0.001) but there was no association between leptin levels and sleep quality (p=0.177). Mediation analysis reinforced the direct effect of sleep quality on memory function, but leptin had no indirect effect as mediator over the sleep-memory association. Moderation analysis revealed that leptin acted as a moderator in the relationship between sleep quality and memory (p< 0.001), with increased leptin levels enhancing the effect of sleep quality over memory function.

Conclusion

Leptin, a hormone involved in appetite control and energy balance, acts as a moderator of the relationship between sleep quality and memory performance. Individuals with high leptin levels are more susceptible to the negative effects of poor sleep on memory. This finding highlights the complexity of the interaction between sleep, memory, and metabolic factors, such as leptin, and its potential implications for overall health and well-being.

Support (if any)

AFIP, FAPESP, CNPq.
0059 A Transformer Model for Predicting Cognitive Impairment from Sleep
Authors: Song Tzu-An , Malekzadeh Masoud , Saxena Richa , Purcell Shaun M · , Dutta Joyita
Published: April 2024

Introduction

Sleep disruptions have been found to have a strong association not only with normal cognitive decline that occurs with age, but also with dementia caused by neurodegenerative diseases such as Alzheimer's disease (AD). Predictive techniques that can automatically detect cognitive impairment from an individual’s sleep patterns have broad clinical and biological significance. We present an innovative multi-task learning paradigm that leverages deep learning to simultaneously predict cognitive performance measured from two distinct cognitive tests, Cognitive Abilities Screening Instrument (CASI) and Digit Symbol Coding Test (DSCT), using whole-night sleep electroencephalography (EEG) data, sleep stage labels, and covariates in an elderly cohort.

Methods

Our study utilizes data obtained from the Multi-Ethnic Study of Atherosclerosis (MESA) participants randomly assigned to two cohorts: validation (N=470) and training (N=1,110). Our approach uses a multi-task transformer architecture to learn complex patterns of sleep architecture for binary cognitive status prediction. The ground truth binary cognitive status labels (low and high score groups) are generated by using the dataset's median CASI and DSCT values as the thresholds. We use sleep EEG, sleep stage labels, and covariates as inputs and binary CASI and DSCT cognitive score classes as targets to train and validate our model.

Results

Our transformer model achieves an overall accuracy (OA) of 70.21% with an F1-score of 71.43% for CASI and 70.85% with an F1-score of 69.35% for DSCT. In comparison, a neural network trained using 132 handcrafted sleep features as inputs has an OA of 59.57% with an F1-score of 60.08% for CASI and 60.64% with an F1-score of 60.04% for DSCT. The OA and F1-score margins are 10.64% and 11.35% for CASI and 10.21% and 9.31% for DSCT, respectively.

Conclusion

We introduced a deep multi-task learning framework for predicting a person's cognitive status using whole-night sleep EEG data. Our transformer model outperforms the comparison method trained using the handcrafted features in OA and F1-score by a large margin. To our knowledge, this is the first deep learning model for jointly predicting cognitive status based on two different testing instruments from an individual’s sleep EEG data.

Support (if any)

This work was supported in part by the NIH grant 1R21AG068890-01.
0064 Sleep Loss Affects Item and Source Memory Differentially as a Function of Serotonin Transporter (5-HTTLPR) Genotype
Authors: Skeiky Lillian , Lundholm Kirsie , Hovland Sean , Whitney Paul , Hinson John , Van Dongen Hans , Kurinec Courtney
Published: April 2024

Introduction

Remembering relationships between items (information) and the contexts (sources) in which they are framed is crucial for everyday functioning. Total sleep deprivation (TSD) impairs this ability, with evidence suggesting that TSD affects source memory even when items are remembered. Source memory deficits imply problems with associative memory, which relies on hippocampal functioning, known to be altered by TSD. Serotonin is highly expressed in the hippocampus, is influenced by TSD, and may be part of a mechanism by which TSD degrades source memory. We investigated the association between 5-HTTLPR, a functional length polymorphism of the human serotonin transporter gene (SLC6A4), and item and source memory during TSD.

Methods

N=34 healthy adults (ages 27.3±4.9y; 18 female) participated in a 4-day/3-night laboratory TSD study. Participants underwent 38h TSD, preceded and followed by 10h sleep opportunities. At baseline and 24h later during TSD, they completed an item/source memory task. Participants listened to a list of 60 words each presented by a male or female speaker (study phase). They were then tested for recognition of the words (items) out of 60 old and 60 new words presented visually, and were asked to identify the corresponding speakers (sources, male or female).

Results

The genotype distribution was in Hardy-Weinberg equilibrium (P=0.34), with 35.3% long/long, 41.2% long/short, 23.5% short/short. Mixed-effects ANOVA showed a significant adverse effect of TSD for both item recognition (P< 0.001) and source recognition (P< 0.001), where TSD degraded source memory even when item recognition was accurate. There were no 5-HTTLPR genotype effects on item memory. However, there was a significant main effect for genotype on source memory (P=0.019), and a genotype by TSD interaction (P=0.018). For accurately recognized items, source memory was largely preserved for the short/short genotype but impaired for carriers of the long allele, and especially the long/long genotype.

Conclusion

5-HTTLPR genotype predicted source memory deficits from TSD, distinct from item memory deficits unaffected by genotype, which confirms that item and source memory deficits due to TSD are dissociable. Furthermore, TSD’s impact on binding of items and sources in memory may be mediated by hippocampal serotonin.

Support (if any)

NIH R21CA167691, WSU Anthony Marchionne and Foundry10 Bridge fellowships
0065 Determining the Impact of Extended Wakefulness on Memory Retention
Authors: Varghese Anju , Kurinec Courtney , Hinson John , Whitney Paul , Satterfield Brieann
Published: April 2024

Introduction

It has been well-established that the rate of forgetting slows if learning is followed by a period of sleep versus wake. Although several studies compared rates of retention for material learned before sleep or sleep loss, none have explicitly examined how extended wake, without intervening sleep, impacts the rate at which information is forgotten. To explore this further, we investigated the effects of sleep deprivation on memory retention over extended wakefulness in dayshift (DS) versus nightshift (NS) participants.

Methods

N=22 adult shift workers (DS: n=17 and NS: n=5; aged 38.3±8.9 years; 12 females) participated in a 36-hr in-laboratory study. They adhered to their habitual wake time (DS: 5:50am; NS: 1:15pm) at home and arrived at the laboratory at 8:00am (DS)/8:00pm (NS). After a 2-hr acclimation period, participants followed a 24-hr constant routine protocol, which included continuous wakefulness. During the study, participants completed a memory task requiring the memorization of 20 nouns, ranging from 4-6 letters. The words were each individually presented on a computer screen for 10 sec. Recall sessions occurred immediately (session 1; 1+ hrs awake), 1 hr (session 2; 2+ hrs awake) and 24 hrs (session 3; 25+ hrs awake) post-memorization. The variable of interest is the proportion of words correct.

Results

A mixed-effects ANOVA, with fixed effects of session (1-3), shift (day vs. night), and their interaction, controlling for age, and a random intercept for participants, showed a significant main effect of session on the proportion of words correct (F[2,38]=36.65, p< 0.001). Overall, the proportion of correctly recalled words decreased across sessions, with performance decreasing 12.5% from immediate to 1-hr, 18.8% from 1-hr to 24-hr, and 29.0% overall from immediate to 24-hr. Shift type and age did not significantly affect performance (p>0.05).

Conclusion

The outcomes of this study replicated previous findings demonstrating the degradation of memory recall under the influence of sleep deprivation. The pattern of performance aligns with the conventional forgetting curve, in which forgetting occurs rapidly soon after learning, typically within the first hour, with the rate gradually decreasing over time. Future research will examine if continuous wakefulness exacerbated this memory decline.

Support (if any)

CARE Fund FY22-POP-02; HSSA; ARO W911NF2210223
0073 Do Slow Wave Sub-types Serve Distinct Roles in Sleep Homeostasis and Plasticity?
Authors: Noh Eunsol , Lokhandwala Sanna , Spencer Rebecca
Published: April 2024

Introduction

Recent research distinguishes two slow wave (SW) subtypes: slower (SSW) and faster slow waves (FSW). Early research on these subtypes suggests that FSW positively correlate with sleep pressure, while SSW are associated with memory. Developmental data from children who nap provide an opportunity to test this distinction. Prediction 1: If FSW are associated with sleep pressure, we expect more FSW during overnight sleep when children do not nap compared to overnight sleep following daytime naps. Prediction 2: If SSW are associated with memory, we expect stronger and more synchronized coupling between spindles (SP) and SSW compared to FSW, reflecting memory processing.

Methods

This is a secondary analysis of data from 25 children (3-5 yrs). Children participated in two conditions; they either napped (NO) or stayed awake (WO) during the daytime nap interval. The nap and subsequent overnight sleep in both conditions was PSG-recorded. SWs (0.5-4 Hz) and SPs (10.3-13.3 Hz) were detected during NREM sleep in the frontal region. To distinguish between slow and fast SWs, the transition frequency from the down-to-up state of SWs was utilized. Coupling amount (strength) and direction of coupling (phase) were quantified for both SSW-SP and FSW-SP coupling.

Results

Prediction 1: A higher occurrence of FSW were observed during WO compared to NO (t(24)=-2.70, p=0.01). However, after adjusting for NREM sleep duration, FSW density did not differ between NO and WO (p=0.75). Prediction 2: SSW-SP coupling strength was lower compared to FSW-SP coupling strength during WO (t(24)=-2.43, p=0.02), but there were no differences in the NO condition (p=0.25). Additionally, there were no significant differences in the coupling phase between SSW-SPs and FSW-SPs in either overnight bout (p>0.45).

Conclusion

Increased sleep pressure (nap absence) did not directly affect FSW density. Instead, the absence of naps extended NREM sleep duration, elevating FSW occurrence. Moreover, SSW-SP coupling was weaker than FSW-SP coupling and only during WO, contrary to our prediction that SSW are associated with learning. While it is possible that SSW and FSW functionality is still developing at this age, these data fail to support predictions of the distinct role of SW subtypes.

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0074 Sleep Slow Oscillations Differ in Depth Profiles Based on Their Coupling with Spindles: A Classification Study
Authors: Dey Sounak , Malerba Paola , Mednick Sara C
Published: April 2024

Introduction

Slow oscillations (SOs) are large amplitude events in the electroencephalogram and contribute to sleep functions including homeostasis and consolidation of episodic memory. Complexes of one SO and one sleep spindle, where a spindle follows an SO trough within a short delay, are causally connected to sleep-dependent episodic memory improvement. In this study, we compare the cortical-subcortical brain currents that underlie SOs paired to spindles (SO+) and unpaired SOs (SO-), with the goal of identifying whether networks of activations are different in the two cases. This knowledge is essential to understanding the mechanisms of memory consolidation across brain regions.

Methods

Full-night polysomnography data (64 channel EEG) was acquired in the Mednick Lab for 22 typical young adult participants. Individual SOs and spindles were detected with in-house algorithms at every EEG channel. SO current sources at multiple time instances were found using source estimation software (Brainstorm) and encoded in a matrix representation of region-by-time, where each matrix was labeled as SO+ or SO-. Region-by-time features with strongest differentiation between SO+ and SO- were identified with multivariate feature ranking; classification with K-nearest neighbors and random forest evaluated with Matthew’s Correlation Coefficient (MCC) tested differentiability in a pooled dataset. We analyzed light (S2) and deep NREM (SWS) sleep separately.

Results

All classification algorithms achieved high MCC scores, suggesting structural differentiation between SO+/SO-. Within-individual models did not achieve high MCC scores when used to classify another individual’s SOs, refuting generalizability across subjects. Subcortical/cortical activity in SO+ vs. SO- was also found to be distinguishable up to 1 second before the SO trough. Additional analysis showed overall higher region-by-time feature interdependence underlying SO+, with the most significant features being the bilateral cortex, hippocampus, putamen, and pallidum.

Conclusion

Successful classification of SO+/SO- indicates the presence of structural differences in cortical-subcortical activation during SO that are spindle-coupled compared to uncoupled. Combined with feature analysis identifying distinct network activations in coupled vs uncoupled SOs, our study suggests a potential functional difference. Ongoing work includes investigating the various feature dependencies that exist within our dataset as well as conducting confirmatory analyses in a separate data subset.

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0079 Preliminary Analysis Reveals Link Between Visual Attention and Sleep Duration in Alzheimer's Disease
Authors: Rempe Maggie , Garrison Grant , Springer Seth , Glesinger Ryan , Okelberry Hannah , Petts Aubrie , Embury Christine , Wilson Tony
Published: April 2024

Introduction

Sleep disturbances have been shown to relate to the development of Alzheimer’s disease (AD) and its associated cognitive deficits, including visual attention function. Here, we investigated the potential interactive and additive effects of sleep disruption and AD on visual attention performance and its underlying neural mechanisms.

Methods

Preliminary analysis included 33 participants, 10 patients on the AD spectrum (mild cognitive impairment (MCI) and AD; 7 females; Mage: 70.24) and 23 cognitively-healthy older adults (17 females; Mage: 67.47). Participants completed a visual search task during magnetoencephalography (MEG). Participants also wore an Actigraph device on their non-dominant wrist for a two-week period. Actigraph data were cleaned using sleep diaries and analyzed using the Cole-Kripke algorithm. Total sleep time (TST) was calculated for each night of sleep and averaged across all nights of sleep collected. The MEG data were transformed into the time-frequency domain and significant task-related oscillatory responses were source-imaged using a beamformer.

Results

Behavioral analysis of the visual search task revealed a significant condition effect, such that reaction times (RT) in the conjunctive trials were significantly longer than those in the feature condition (p < .001). There was a trending group-by-condition interaction on RT (p = .080), such that patients on the AD spectrum showed larger differences in reaction times between conditions than healthy controls. Additionally, there was a significant group by TST interaction on RT (p < .001) showing that patients on the AD spectrum with less sleep had longer RT, while there was no such relationship in the controls. Regarding the MEG data, we observed robust neural responses in theta, alpha, and beta frequency bands. Analysis of source-imaged neural responses in the alpha range revealed significant conditional differences in the right posterior temporal lobe (p < .005), a significant group-by-condition interaction in the right temporoparietal junction (TPJ; p < .005), and interestingly, a group-by-TST interaction on conditional differences in alpha power (p < .005) in right occipital and cerebellar regions.

Conclusion

Our preliminary results show key relationships between total sleep time, visual attention behavioral performance, and neural recruitment, and how these relationships may differ in AD spectrum conditions.

Support (if any)

R01-MH116782, R01-MH118013
0082 Sleep Health and Daytime Cognitive Function: Data from the National Sleep Foundation Sleep in America Poll
Authors: McNeil Kiley , Kennedy Kathryn , Gorovoy Suzanne , Killgore William , Dzierzewski Joseph , Grandner Michael
Published: April 2024

Introduction

Previous studies have shown that poor sleep is generally associated with daytime dysfunction. But few studies have examined this relationship in the general population across many dimensions of sleep health and it is not clear which sleep variables are most salient.

Methods

Data were collected as part of the National Sleep Foundation Sleep In America Poll. The population-based sample (N=1,042) provided data on a range of sleep questions. For the present analyses, self-reported difficulty concentrating during the day was examined as a nominal outcome (none vs occasional or frequent), with population-weighted regression analyses adjusted for age, sex, race/ethnicity, education, income, and PHQ2 depression score. Independent variables included sleep satisfaction, feeling refreshed, daytime energy, difficulty falling, frequent nighttime awakenings, difficulty resuming sleep, satisfaction with weekday and weekend sleep duration, ability to feel relaxed, overall sleep quality, weekday and weekend bedtime, waketime, time in bed, and sleep duration, perceived sleep need, and days/week (0-7) of: feeling well-rested, having trouble falling or staying asleep, sleep impacts functioning, daytime sleepiness, and sleep medication use. Bonferonni correction (0.05/26) was used.

Results

The following were associated with frequent daytime cognitive problems: poor sleep quality (RRR=17.9), fewer days well rested (RRR=0.66/day), and more days with difficulty falling asleep (RRR=1.56), difficulty staying asleep (RRR=1.47/day), days sleep impacts functioning (RRR=1.78/day), and days of daytime sleepiness (RRR=1.22/day), less sleep duration on weekdays (RRR=0.58/day) and more sleep debt (RRR=1.65/hr), low sleep satisfaction (RRR=33.93), rarely feeling refreshed (RRR=34.68), low energy (RRR=70.41), severe difficulty falling asleep (RRR=19.23), waking up (RRR=15.63), resuming sleep (RRR=12.86) and feeling relaxed (RRR=65.66), and dissatisfaction with sleep duration on weekdays (RRR=45.15) and weekends (RRR=28.42). In a stepwise regression model examining daytime concentration difficulties as an ordinal variable, after adjusting for covariates, the variables that explained the most unique variance were (in order) days/week sleep impacts functioning, ability to become relaxed, daytime energy, and difficulty waking in the night.

Conclusion

Many indicators of sleep health were associated with daytime dysfunction, implicating sleep duration, quality, efficiency, and daytime effects of sleep. Efforts might ideally focus on the daytime impacts of sleep rather than nighttime experiences.

Support (if any)
0083 You Don’t Snooze, You Lose (Awareness): Sleep’s Role on Awareness of Cognition in Mild Cognitive Impairment
Authors: Costa Amy , McCrae Christina , O'Brien Jennifer , Curtis Ashley
Published: April 2024

Introduction

In adults with Mild Cognitive Impairment (prodromal phase of Alzheimer’s disease; MCI), the level of awareness of cognitive functioning varies significantly. A lack of awareness of cognitive functioning may interfere with monitoring of disease progression and opportunities for intervention. Therefore, understanding mechanisms associated with this relationship is critical. Given age-related changes in sleep and known relationships between sleep health and cognition, this pilot tested whether sleep moderates associations between subjective and objective cognition in older adults with MCI.

Methods

Older adults with MCI (N=46, Mage=68.2 years, SD=6.1 years, 33 women) completed one week of sleep diaries [averages of sleep onset latency (SOL), total sleep time (TST), sleep efficiency (SE)], Cognitive Failures Questionnaire (sub-scores CFQ-memory, CFQ-distractibility, CFQ-blunders), and cognitive tasks [Cambridge Brain Sciences; Polygons (processing speed), Feature Match (attention), Double Trouble (attention/inhibition), Digit Span (working memory)]. Multiple regressions tested if sleep parameters moderated associations between subjective and objective cognition, covarying for depressive symptoms and number of medical conditions.

Results

SE moderated associations between Polygons and CFQ-blunders (R2-change=.08, p=.03). Specifically, at highest SE, slower processing speed was associated with more blunder complaints (B=-.10, p=.04). Additionally, SE moderated associations between Digit Span and CFQ-distractibility (R2-change=.06, p=.03) and CFQ-blunders (R2-change=.12, p=.004). Specifically, at lowest SE, worse working memory was associated with less distractibility (B=3.01, p=.002) and blunders (B=2.45, p<.001) complaints, while at highest SE worse working memory was associated with more blunder complaints (B=-2.48, p=.04).

Conclusion

Preliminary findings suggest in older adults with MCI, lower sleep efficiency may exacerbate discrepancies between objective and subjective cognition, while higher sleep efficiency may converge this relationship. Sleep efficiency should be considered to fully understand the level of awareness of cognitive functioning in older adults with MCI. Critically, these findings may help identify those at risk of further cognitive decline. While future prospective studies are warranted, present findings suggest a potential next step is to examine whether behavioral treatments for insomnia (e.g., Cognitive Behavioral Therapy for Insomnia, cognitive training) may also change the relationship between objective/subjective cognition.

Support (if any)

This research was supported in part by the University of Missouri School of Medicine TRIUMPH award (PI: Curtis).
0086 Early Evidence for Dynamic, Day-to-day Associations Between Working Memory and Sleep in Pre-adolescent Youth
Authors: Simon Katharine C , Duggan Katherine A , Galut Lia , Polk Spencer , Rao Uma , Borelli Jessica , Rahmani Amir , Mednick Sara C
Published: April 2024

Introduction

The transition to adolescence is marked by critical shifts in sleep, including increased variability as well as delayed bedtimes, reduced total sleep time (TST), and reduced homeostatic sleep pressure. Sleep supports healthy brain development, and insufficient sleep impairs brain development in children and adolescents. Short-term experimental manipulations of sleep disturbance and deprivation in adults leads to dysfunction in declarative and working memory. The few experimental studies in youth suggest their cognitive abilities may be more resilient to sleep loss, but these typically include only one night of sleep manipulation. Here, we examined this phenomenon across a week of data.

Methods

Data was used from eleven 9- to 13-year-olds (M = 12.52, SD = 1.4, F = 5) in an ongoing measurement burst longitudinal study spanning one year. For seven consecutive days, participants completed daily sleep diaries, and the working memory task, the O-SPAN, which consists of remembering letters intermixed with math equations. Multilevel models which adjusted for age and sex were used to examine the bidirectional associations between sleep and cognitive performance at the between and within-subjects levels.

Results

Within-subjects (daily) variation in sleep duration, relative to each child’s typical sleep duration, was related to better working memory performance at trending significance. Within-subjects (daily) variation in working memory, relative to each child’s typical working memory performance, was related to significantly longer sleep duration. There are currently no statistically significant associations at the between-subjects level.

Conclusion

Our preliminary results suggest there are within-person, dynamic fluctuations in sleep duration and working memory in adolescents. On nights when adolescents sleep better, their working memory improves (and vice versa). Our ongoing day-to-day investigation of the role of sleep on cognition (target N=60) provides insight into the nuanced role sleep plays, especially along the performance spectrum. Future analyses in this ongoing study will evaluate dependencies in the data structure across the week, as well as developmental trends in sleep-memory associations. The current results are novel and suggest longitudinal methods are critical in the analysis of sleep and cognition in development.

Support (if any)

Award to KS: NICHD/NIH K08HD107161
0087 Effects of a Dual Orexin Receptor Antagonist on Anxiety-like Behavior and Cognition in a Mouse Model of TBI
Authors: Carey Sean , Zielinski Mark , Craig John , Babb Jessica , Kaplan Gary
Published: April 2024

Introduction

Mild/moderate traumatic brain injuries (TBIs) often occur in the frontal cortex and can induce prolonged impairments in sleep, cognition, and anxiety. Orexin is a neuropeptide that activates two receptors that stimulate monoamine activation in the brain to induce wakefulness. We aimed to determine if a dual orexin receptor antagonist (DORA) could improve prolonged cognitive impairments in mice that received TBI.

Methods

Two-month-old male and female C57BL/6J mice were randomly assigned to treatment groups. Mice received a craniectomy and TBI in the frontal cortex by controlled cortical impact, a craniectomy only (sham), or neither. Mice received a vehicle (placebo) or DORA by gavage for 2 consecutive days 24 h, 2 wks, and 1 m after the TBI or control treatments. Two-months after the TBI or control procedures, the mice were subjected to the open field and novel object familiarization. The following day, mice were administered the vehicle or DORA, and subjected to the elevated-plus maze (EPM), open-field maze, and novel object recognition (NOR) test. Significance was set at p<.05.

Results

No significant difference between the control and sham treatments were overserved in NOR. Time spent exploring the novel object vs. the familiar object was significantly increased in both control and sham groups that received the vehicle indicating intact cognition (p=0.001 and p=0.0001, respectively). However, TBI reduced time spent exploring the novel object under vehicle conditions and after DORA treatments without TBI resulting in no significant differences in novel vs. familiar object exploration. The combined DORA and TBI treatment group spent significantly greater time exploring the novel object (p=0.047), although exhibited significantly less movement duration compared to other controls (Sham Vehicle p=<.0001; Control Vehicle p=<.0001). No significant differences in the EPM or open-field maze were found with experimental treatments.

Conclusion

These data further implicate mild/moderate TBI in impairments in cognition. However, due to the increased immobility caused by the DORA, we cannot conclude an interaction of DORA treatment with TBI on cognition using a NOR test that is dependent on movement activity.

Support (if any)

VA SPiRE Award (GK) I21RX003722; VA Merit Award (MZ) I01BX005379
0088 Sleep Structure and Heat Dissipation Influence Subjective Sleep Onset Latency in Young Adult Human Subjects
Authors: Aritake-Okada Sayaka , Iijima Ryusei , Kadooka Akari , Sugawara Kairi , Fushimi Momo , Hosoe Mizuki
Published: April 2024

Introduction

Several previous studies reported that humans can estimate the time that has elapsed during sleep (time estimation ability; TEA). Although research on the TEA during sleep has advanced in the field of sleep research, few studies have focused on the relationship between the subjective sleep onset latency (SOL), which is an indicator of TEA, and objective sleep structures, heat dissipation, and body temperature. The current study examined the relationship between subjective SOL, sleep structure, changes in skin and body temperature, and subjective evaluation of sleep in healthy young adults to elucidate the pathophysiological mechanisms of insomnia.

Methods

Twenty-eight subjects (7 men and 21 women, mean age: 21.54 ± 0.50 years) with no sleep problems participated in a 1-hour polysomnographic recording that obtained objective sleep parameters during the daytime while skin and body temperatures were recorded. The distal–proximal skin temperature gradient (DPG) was calculated. The duration of stage W, stage N1, stage N2, and stage N3 and stage R sleep, sleep latency, wake after sleep onset, total sleep time were calculated for all PSG recordings. Power spectral analysis using the fast Fourier transform algorithm was conducted. Also, subjective parameters, such as subjective SOL, sleep time, and restorative sleepiness, were evaluated before and after sleep. The study was approved by the Ethics Committee of Saitama Prefectural University.

Results

Almost all subjects estimated their sleep latency as being longer than their actual SOL (13.70 min vs. 7.57 min). Objective SOL was significantly correlated with each sleep stage parameter whereas subjective SOL was negatively correlated with stage N2 sleep duration, slow-wave activity and δ-power, and ΔDPG (the degree of reduction of heat dissipation before and after lights-off). Stepwise regression analysis showed that ΔDPG was the strongest predictive factor in explaining the length of subjective SOL.

Conclusion

The degree of heat dissipation before and after lights-off contributed most to the sensation of falling asleep in healthy young adults, and stage N2 duration and slow wave components immediately after falling asleep may be related to the sensation of falling asleep. This finding may be helpful for elucidating the physiological mechanisms of insomnia and its treatment.

Support (if any)