bluuebunny/crossref_metadata_2025_split huggingface dataset:
0088 Gravity Dreams Following a Virtual Reality Flight Simulation
Authors: Picard-Deland C , Pastor M , Solomonova E , Paquette T , Nielsen T 
Published: May 2020

Abstract

Introduction
Flying is a prevalent but infrequent experience in dreams. Despite a broad interest in such unique dream experiences, there is still no experimental procedure for reliably inducing them. Our study aimed 1) to induce flying dreams in the laboratory using virtual reality (VR), 2) to examine phenomenological correlates of flying dreams, such as lucidity and emotions and 3) to investigate the dynamics of dreamed gravity imagery in relation to participant state and trait factors.

Methods
A total of 137 healthy participants (24.01±4.03 y.o.; 85 F; 52 M) took part in a custom-built immersive VR task in which they learn how to ‘fly’ as precisely and quickly as possible, engaging vestibular, motor and visuo-spatial systems. Dreams were collected a) from home dream journals for 5 days before and 10 days after the laboratory VR task and b) after a 90-min morning nap in laboratory. Dream reports were scored by 2 independent judges for flying and other gravity-related imagery. Linear mixed models statistics were used to compare dreams from this cohort with a separate control cohort (N=52) that followed a similar protocol in the same lab but did not undertake a virtual flying task.

Results
The VR task successfully increased the likelihood of experiencing flying in dreams from both the laboratory nap (7.1%) and the following night (10.6%) compared to baseline (1.3%) and the control cohort on those days (Lab: 2.4%; following night: 0%). In contrast, the occurrence of other gravity imagery showed no differences. Flying dreams were altered qualitatively, exhibiting higher levels of lucid-control and emotional intensity after VR exposure. Moreover, various factors such as sex, prior dream experiences and sensory immersion in VR differentially modulated flying dream induction.

Conclusion
Our findings provide both quantitative and qualitative insights into flying dreams that may facilitate understanding of these typical dream experiences and future developments in dream flight-induction technologies.

Support
Natural Sciences and Engineering Research Council of Canada
0091 Sleep as a Mediator of the Relationship Between Exercise and Self-Reported Cognitive Function
Authors: Chappel-Farley M G , Nan B , Grill J D , Mander B A , Yassa M A , Benca R M 
Published: May 2020

Abstract

Introduction
Insufficient sleep and sedentary behavior are associated with cognitive decline. How sleep and physical activity interact to influence cognition is not fully understood. This study sought to examine whether self-reported sleep and exercise impact subjective cognitive complaints across adulthood.

Methods
Self-report questionnaire data from 2,744 adults (μ=56.18 yrs/old; 63.8% F; μ=16.36 yrs/edu) in the University of California Irvine Consent-to-Contact Registry were analyzed. Multiple regression models, analysis of covariance, and ordinary least squares path analysis were conducted to investigate relationships among the Cognitive Function Instrument (CFI), Medical Outcome Study Sleep Scale (MOS-SS) Subscales, and exercise frequency. All models adjusted for education, sex, age, BMI, medical comorbidities, depression, cancer diagnosis, and antidepressant usage. Individuals taking medications known to affect sleep or with a diagnosis major psychiatric illness were excluded from analyses.

Results
All MOS-SS Subscales significantly predicted CFI score (all p&lt;0.001). Individuals who exercise &gt;3times/week had significantly lower scores on the CFI (p&lt;0.05), Sleep Problems Index I & II (both p&lt;0.05), Somnolence Subscale (p&lt;0.01), and higher scores on the Sleep Adequacy Subscale (p=0.001). Mediation analyses revealed that all subscales, aside from the Sleep Disturbance Subscale, mediated the relationship between exercise frequency and CFI Score (Bootstrapped CI’s did not include zero).

Conclusion
More self-reported sleep disturbance and greater daytime sleepiness are associated with more subjective cognitive complaints. Individuals who exercise more frequently report lower daytime sleepiness and higher quality sleep. The effects of exercise frequency on cognitive complaints appear to be mediated by the impact of exercise on sleep. These results suggest that sleep health may be a crucial consideration when evaluating outcomes of exercise-based therapies aimed at delaying the onset of cognitive impairment.

Support
The C2C registry was made possible by a donation from HCP, Inc. and is supported by NIA AG016573 and NCATS UL1 TR001414.
0094 The Effect of Zolpidem on Sleep-Dependent Declarative Memory Consolidation
Authors: Zhang J , Mednick S 
Published: May 2020

Abstract

Introduction
Sleep plays a critical role in memory consolidation. At the same time, about 20% of population in the U.S. suffer from sleep disorders or deprivation, and about 16% of them reported using sleep aids (CDC, 2015). However, the effect of sleep aids on sleep-dependent memory consolidation remains unclear. Previous studies have observed an improvement in sleep-dependent declarative memory consolidation with zolpidem over a daytime nap (Mednick et al., 2013). The current study investigates the effect of zolpidem on declarative memory consolidation over a night of sleep and over 24 hours.

Methods
This study employed a double-blind, placebo-controlled, within-subject design, in which every subject (N=26, 12 females) experienced both zolpidem and placebo. All subjects were healthy, college-aged adults without sleep disorder. A 32-channel electroencephalogram cap was used to record brain activity during sleep. Word paired-associates task was used to evaluate memory performance. Participants reported to the laboratory in the evening, performed word paired-associates task (test1), then ingested either zolpidem or placebo before sleep. They were tested on the task in the following morning (test2) as well as in the following evening (test3). Paired-sample t-tests for retrieval difference scores between placebo and zolpidem conditions were conducted.

Results
Participants showed similar baseline performance on the word paired-associates task (test 1, p=0.45). Zolpidem condition showed higher memory retention compared to placebo 24hr after drug ingestion (test3-test1, t₂ 5=2.09, p&lt;0.05). The improvement in performance for zolpidem condition occurred across the following day (test3-test2, t₂ 5=2.22, p&lt;0.05), as no difference was observed between conditions after sleep (test2-test1, t₂ 5=0.34, p=0.74)

Conclusion
Consistent with previous studies, participants showed better memory performance after taking zolpidem compared to placebo. However, the current study showed that the improvement in memory occurred across a day of wakefulness after nighttime drug ingestion, while other studies observed improvements shortly after sleep, indicating a potential delayed benefit of zolpidem on memory consolidation.

Support
This work was supported by the Office of Naval Research grant N00014-14-1-0513
0095 Sleep Boosts Schema-Related Memory Consolidation and Inference
Authors: Golkashani H A , Chee M W 
Published: May 2020

Abstract

Introduction
A schema is a previously learned framework of information that helps the learning and retention of new, but related material. We examined how sleep, compared to staying awake following the acquisition of a schema, and thereafter novel material, affects the consolidation of new memoranda that were either embedded or not into the learned schema. We also tested if sleep affects the inference of hierarchy within these memoranda.

Methods
54 adolescents (mean age 16.6 years; 26 males) learned the age hierarchy of 7 galaxies by viewing adjacent pairs, one at a time e.g. A-B, D-E, and making transitive inferences (If B&gt;C and C&gt;D then B&gt;D). Once this schema was learned to criterion, participants learned two new sets of galaxies: one set comprised 5 galaxies from the schema and 4 new, intercalated galaxies; the other contained 9 unfamiliar galaxies (schema & no-schema conditions). Memory for galaxy ordering was tested immediately after learning and again after 12-hours. One group(n=25) was kept awake in the day, while the other group (n=29) slept overnight for 8-h. Memory was tested for galaxies that were directly adjacent e.g. A-B, as well as for ‘inference pairs’ that were two apart: e.g.:(B-D, C-E).

Results
Change in memory following the respective 12-hour intervals was analyzed using a mixed ANOVA with schema (schema, no-schema) and pair-type (adjacent, inference) as within-subject factors and sleep group (sleep/awake) as the between-subjects factor. There were significant main effects of sleep and pair type as well as a significant interaction, where schema-related memory was better preserved in the sleep group. This group also had higher performance for inference pairs embedded within the original schema.

Conclusion
Sleep benefitted the consolidation of new memoranda embedded in a schema. This benefit was stronger for non-adjacent inference pairs suggesting that sleep boosts insight into non-explicitly declared, hierarchically organized information.

Support
Supported by NMRC/STaR/0015/2013 and NRF2016-SOL002-001
0098 The Role of Sleep in Novel Category Learning in Infancy
Authors: Sucevic J , Plunkett K 
Published: May 2020

Abstract

Introduction
A growing body of research suggests that sleep has an important role in consolidating newly learnt information and generalising this knowledge to novel instances (e.g. Djonlagic et al., 2009). The effects of sleep on early categorisation abilities haven’t been investigated so far and thus the aim of this study is to examine the role of sleep in formation of category representations. Two experiments were conducted. Experiment 1 set out to determine 4-months-old infants’ ability to form novel visual categories when category formation test immediately followed learning. Experiment 2 investigated the impact of sleep on category consolidation by testing category formation after a 2 hours delay.

Methods
Both experiments employed eye-tracking familiarisation-novelty-preference paradigm. In Experiment 1, infants were familiarised with a set of exemplars from a novel category. Immediately after the familiarisation phase, infants’ category formation was tested and their looking references were used as an index of category learning. Experiment 2 tested consolidation of the newly acquired categories by introducing a delay between the familiarisation and the test phase. Half of the participants took a nap during the delay, whereas the other half remained awake. Polysomnography was recorded using a standard PSG protocol. Sleep stages were scored according to the AASM guidelines, and sleep spindles were detected using an adapted algorithm for children.

Results
Results of the Experiment 1 revealed that infants were able to learn novel visual categories when category formation was tested immediately after learning suggesting therefore that infants are able to extract relevant information and generalise to novel instances. Preliminary results of Experiment 2 (data analysis ongoing) suggested that infants who napped performed better than infants who stayed awake.

Conclusion
The present study suggests that infants are able to rapidly form novel categories, and that consolidation of this knowledge is shaped by the activity following learning.

Support
N/A
0100 Effect of Naps on Preschoolers’ Consolidation of an Emotional Storybook
Authors: Holmes J F , Deighan M K , Miranda N W , Mason G M , Spencer R M 
Published: May 2020

Abstract

Introduction
Naps are known to benefit emotional memory consolidation in preschoolers, though improvement is not evident until the following day. The mechanisms by which naps aid emotional memory, and how they differ from those facilitating more neutral declarative memory consolidation, are currently unknown. In this study, we used an emotional storybook task to assess change in memory for emotionally salient vs. neutral events across a nap and overnight sleep. PSG was included to explore sleep physiology correlates.

Methods
Preschool children (n = 9; Mage= 43.2 months) were read a novel storybook featuring negative and neutral events. Memory of story events was probed through sets of multiple-choice questions and assessed at three time points: immediately following the story, following a nap or equivalent wake period (within-subject; counterbalanced; separated by ~1 week), and 24h post-encoding. PSG was recorded during the nap period and both subsequent overnight sleep bouts.

Results
Memory performance across time points was assessed via change scores. Recall of story events did not differ between conditions from immediate to post-nap/wake assessment. When probed the following morning, children better remembered events when a nap took place the day prior (F(1,7) = 8.848, p=.021). This delayed nap benefit correlated with time spent in NREM2 during the nap (r=.91, p=.017). No differences were found between recall of negative vs. neutral events at any time point or between conditions.

Conclusion
Our results show a delayed benefit of napping on recall of a storybook, though at present no preference for emotional events is seen. Time spent in NREM2 during the nap was strongly associated with our finding, likely reflecting the declarative memory benefits conferred from this stage. Further analyses will include overnight sleep physiology to explore differential enhancement between event types, and possible interactions with nap microstructure.

Support
This work was supported by NIH R01 HL111695.
1017 An Integrated Behavioral Therapy for Positive Airway Pressure Adherence and Insomnia Reduces Nocturia Frequency
Authors: Fung C H , Martin J L , Dzierzewski J M , Fiorentino L , Stepnowsky C , Song Y , Zeidler M , Mitchell M , Vaughan E C , Huang A , Markland A , Josephson K , Alessi C 
Published: May 2020

Abstract

Introduction
Nocturia is common among patients with both insomnia disorder and obstructive sleep apnea (OSA) and adversely affects quality of life. Within a randomized controlled trial testing an integrated behavioral therapy for positive airway pressure (PAP) adherence and insomnia for patients with coexisting OSA and insomnia disorder, we examined the impact of the integrated therapy on nocturia frequency.

Methods
Patients aged &gt; 50 years with untreated OSA (apnea hypopnea index &gt; 15) and chronic insomnia disorder were recruited from a VA medical center and randomized to 5 weekly individual integrated behavioral treatment sessions versus control (general sleep education). Nocturia frequency (self-reported average number of nocturia events per night) was assessed at baseline, 3 months, and 6 months. Linear regression models were used to examine relationships between objective PAP adherence (# nights used &gt; 4hrs over the last 30 days) and Insomnia Severity Index (ISI) score (0 [none] - 28 [severe]) and nocturia frequency (0 - 5+/night), and change in nocturia frequency associated with integrated therapy.

Results
Nocturia data were available for 112 participants (treatment=56, control=56; mean age 63 [SD 7], 95% male). Mean nocturia frequency (episodes/night) was 2.1 (SD 1.3; baseline), 1.6 (SD 1.1; 3 months), and 1.7 (SD 1.2; 6 months). Overall, higher PAP adherence (B=.029, p=.008) and ISI score improvement (B=0.05, p=.004) were associated with decreased nocturia frequency at 3-month follow-up. No differences were observed in nocturia frequency between treatment and control participants at baseline (p=.429). Integrated therapy reduced nocturia frequency at 3 months (B=-0.56, p=.020) but not at 6 months follow-up (B=-0.4, p=.081) compared to control.

Conclusion
Nocturia frequency improved with integrated behavioral therapy for PAP adherence and insomnia in veterans (primarily male) with co-existing OSA and insomnia. Additional studies are needed to examine the mechanisms underlying the relationship between the behavioral therapy for PAP adherence and insomnia and nocturia.

Support
VA HSR&D; NIA; VA GRECC
1023 Oncologists’ Beliefs About Medical Marijuana’s Effectiveness for Sleep in Cancer Patients: A Nationally Representative Survey
Authors: Zhou E S , Nayak M M , Braun I M 
Published: May 2020

Abstract

Introduction
Cancer is a qualifying condition for medical marijuana (MM) access in almost every state which has legalized medical use. Over 20% of patients report recent cannabis use to manage cancer treatment side effects, including poor sleep. However, there have been no clinical trials of MM for sleep in oncology populations. This study explores oncologists’ characteristics associated with their views on MM for sleep.

Methods
N=237 medical oncologists completed a mailed survey querying demographics, training history and current practice, and their knowledge and views on MM. In these analyses, we compared oncologists who viewed MM as being equally or more effective than standard treatment approaches to manage poor sleep with those who viewed MM as less effective.

Results
Sixty-four percent of oncologists believed MM to be equally or more effective than standard treatments for poor sleep. They were significantly less likely than peers to have a medical school faculty appointment (53% vs 72%) or self-report sufficient knowledge about MM to make clinical recommendations (42% vs 57%). Oncologists who viewed MM favorably compared to standard treatments for poor sleep were more likely to have recommended its use and to view it as beneficial during end of life care. We identified no differences between groups by age, sex, ethnicity, US vs foreign medical training, patient volume, or whether the state where they practiced had legalized MM.

Conclusion
Oncologists affiliated with a medical school report less knowledge about MM and are more cautious in their views of its effectiveness for treating poor sleep. This may be due to their institutions’ reluctance to draft MM policies for fear of losing federal licensure or their awareness of the limitations of existing data. There are important practice implications related to the likelihood of an oncologist recommending MM for poor sleep.

Support
Hans and Mavis Lopater Foundation.
1026 Associations Between Physiological Arousal and Executive Function in Adults With Chronic Widespread Pain and Insomnia Complaints
Authors: Curtis A F , McGovney K , McCrae C S 
Published: May 2020

Abstract

Introduction
Individuals with chronic widespread pain (CWP) commonly experience increased physiological arousal, insomnia symptoms, and cognitive disturbance. Higher arousal (as measured by heart rate variability, HRV) is associated with worse executive function in healthy adults, suggesting that hyperarousal selectively disrupts prefrontal cortical activity. However, the HRV/cognition relationship in CWP, the moderating impact of insomnia severity, as well as the components of executive function affected, are unclear. The present study assessed independent associations between HRV and components of executive functioning in patients with CWP and insomnia complaints, and evaluated whether these associations depend on insomnia severity.

Methods
Forty-two adults (Mage=46.2, SD=13.7) with comorbid CWP and insomnia complaints (difficulty falling/staying asleep plus daytime dysfunction) underwent 5-minutes of Holter monitoring to assess resting HRV. The root mean standard deviation of successive normal to normal heartbeats (RMSDNN) was computed as the HRV index. Participants completed the Insomnia Severity Index (ISI). Participants also completed three computerized tasks measuring executive function: Stroop task (inhibition), Sternberg task (working memory), and the Balloon Analogue Risk Task (risk taking behavior). Multiple regressions examined whether RMSDNN independently predicted or interacted with ISI to predict cognition, controlling for age.

Results
RMSDNN independently predicted Stroop performance, with higher RMSDNN (lower arousal) associated with lower interference scores (better inhibitory function), B=-.003, SE=.001, p=.029, Full Model R2=.31. RMSDNN and ISI did not independently predict or interact to predict Sternberg/BART performance.

Conclusion
In patients with CWP and insomnia symptoms, reduced physiological arousal was associated with better inhibition, and this did not depend on insomnia severity. Findings highlight the potential underlying role of hyperarousal in a specific component of executive disruption in CWP. Results suggest that treatments aimed at reducing physiological arousal in comorbid CWP and insomnia (e.g., relaxation, HRV biofeedback) may selectively improve inhibitory function. Findings warrant further consideration in larger samples and prospective analyses.

Support
Research was supported by the National Institute of Nursing Research (NR017168; PI: McCrae). Data collected as part of clinical trial NCT02001077 Sleep and Pain Interventions (SPIN2) at the University of Missouri (PI: McCrae).
1031 Exploring the Impact of Cognitive Behavioral Therapy for Insomnia (CBT-I) on Daytime Productivity in Survivors of Breast Cancer
Authors: Kieley J , Walsh N , McCarthy J , Powell E , Garland S N 
Published: May 2020

Abstract

Introduction
Post-treatment insomnia disorder and fatigue symptoms can impair work and daytime productivity in breast cancer survivors. Cognitive Behavioral Therapy for Insomnia (CBT-I) significantly improves insomnia and daytime fatigue. This feasibility study examined whether improving insomnia and fatigue using CBT-I is associated with improved work and activity productivity in breast cancer survivors.

Methods
10 survivors of early stage breast cancer participated in 7 weekly individual CBT-I sessions. The primary outcome was the Work Productivity and Activity Impairment Questionnaire-General Health (WPAIQ-GH) questionnaire. Secondary outcomes were the Insomnia Severity Index (ISI) and the Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF). Assessments were conducted at baseline and post-treatment. Paired samples t-tests examined the impact of CBT-I on productivity and fatigue. Linear regression assessed whether change in fatigue was associated with change in productivity.

Results
Participants had a mean age of 50.8 (range 42-63) and the majority were diagnosed with stage II (60%) cancer. There was a significant reduction in fatigue [t(9)= 2.43, p =.04] and activity impairment due to insomnia [t(9)= 3.105, p &lt;.05] following treatment. Insomnia affected 52% of work productivity at baseline with a non-significant decrease to 15% following treatment [t(3)= 2.25 p= .110]. Reductions in fatigue were significantly associated with reductions in activity impairment [F(1,8)= 7.25, p =.03], accounting for 47.5% of the variability.

Conclusion
Treating insomnia with CBT-I significantly improved daytime productivity, activity impairment, and fatigue. Controlled research with larger sample sizes is warranted to confirm these preliminary results.

Support
Nyissa Walsh is a trainee in the Cancer Research Training Program of the Beatrice Hunter Cancer Research Institute (BHCRI). Dr. Sheila Garland is supported by a Scotiabank New Investigator Award from BHCRI.