bluuebunny/crossref_metadata_2025_split huggingface dataset:
O006 A double-blind randomized placebo-controlled trial on the effect of suvorexant on REM sleep and fear extinction recall
Authors: Schenker M , Zeng L , Lynskey J , Dawson A , Kay A , Rouhi S , Felmingham K , Nicholas C , O’Donoghue F , Jenkins C , Thornton T , Jordan A 
Published: December 2024

Abstract
Disturbed sleep is common after trauma exposure. Individuals seeking relief may consult their GP and are frequently prescribed benzodiazepines. However, these drugs are detrimental as they can impair extinction processes (i.e., the reduction of the conditioned fear response to trauma-related stimuli over time) and thus increase the risk of developing post-traumatic stress disorder (PTSD). Additionally, benzodiazepines may disrupt rapid eye movement (REM) sleep, which is crucial for consolidating emotional memories. Therefore, this study explored suvorexant as a potential alternative to increase REM sleep and improve extinction consolidation compared to temazepam and placebo. Thirty healthy adults (age M=26.23, SD=7.55) completed a two-day fear conditioning paradigm, receiving either drug (double-blinded) before in-lab overnight PSG and returning for extinction recall testing 48h later. There was no significant difference between groups in REM sleep, F(1, 28)=0.01, p=.94. However, there was a significant effect for REM sleep (p=.01) and a REM by drug interaction (p&lt;.01) on extinction recall. Post-hoc tests revealed that in the placebo group, increased REM sleep was associated with a reduced fear response indicative of better extinction recall (p=.01), with no association found in the other conditions (p&gt;.05). Despite unsuccessful REM sleep manipulations, results suggest that in PTSD with disrupted REM sleep, suvorexant might mimic the effect seen with placebo in healthy controls, leading to improved extinction recall. However, this needs to be replicated in a clinical PTSD sample. If confirmed, suvorexant may reduce the risk of PTSD development through improving sleep-dependent extinction processes, thus offering a viable alternative to harmful benzodiazepines.
O008 Temporal Associations between Sleep and Caffeine Consumption in Young Adults
Authors: O’Keeffe K , van den Berg M 
Published: December 2024

Abstract

Aims
Laboratory studies suggest that caffeine consumption has clear and consistent adverse effects on sleep, but epidemiological studies have yielded mixed findings. This study aimed to examine temporal associations between sleep and caffeine consumption in young adults.

Methods
Fifty-one New Zealand young adults (aged 18-25 years) wore an actigraph and completed a sleep diary for 7 days to capture objective and self-reported measures of sleep and self-reported caffeine intake, providing 355 observations. Mixed linear models were conducted to assess temporal associations between caffeine intake (dose and timing) and the subsequent night’s sleep. Lagged models were conducted to assess temporal associations between sleep characteristics and next-day caffeine dose. Independent variables for caffeine and sleep were included in models as within-person and between-person variances from the mean.

Results
Between participants, those who consumed more caffeine per day than the group average had shorter total night time (β=-0.12; p=0.02) and daily (β=-0.12; p=0.02) sleep durations in the subsequent sleep period(s). Conversely, between participants, those with shorter night time (β=-0.06; p=0.004) and daily (β=-0.06; p=0.01) sleep durations consumed more caffeine in total the following day. Within participants, on days with longer night time (β=0.07; p=0. 001)and daily (β=0.05; p=0.02) sleep durations than their personal average, they consumed more caffeine the next day.

Conclusion
There may be a cycle of activity in young adults whereby higher caffeine consumption leads to shorter sleep, which leads to higher caffeine consumption. Further research that accounts for prior sleep history is needed to elucidate associations with sleep characteristics.
O014 Feasibility of evaluating early markers of neurodegeneration in a sleep clinic setting
Authors: Nelson A , D’Rozario A , Hoyos C , Naismith S , Phillips C , Yee B , Grunstein R , Chapman J 
Published: December 2024

Abstract

Introduction
Obstructive sleep apnea (OSA) is an emerging risk factor for cognitive decline. Sleep clinics are well positioned to screen for early biomarkers. We will evaluate the feasibility of cognitive testing and neurodegenerative blood-biomarker collection in a sleep clinic.

Methods
Males and females (&gt;40 years) referred for polysomnography on suspicion of OSA, who consent to be contacted regarding research were invited to participate. Exclusions included existing OSA or any neurological condition.
Participants underwent in-laboratory overnight polysomnography and questionnaires, with additional blood sampling and abbreviated neuropsychological testing.

Results
Over 16 months of recruitment, 968 patients &gt;40 were referred for polysomnography. Of 73 contactable patients who met all eligibility criteria, 59 (80.8%) stated willingness to participate. The only reason for non-participation was unavailability for morning testing (n=14, 19.2%). In preliminary analysis, 57 participants (female=17, age 56.0±10.2) had completed testing.
Moderate-severe OSA (AHI&gt;15) was diagnosed in 24 (42.1%) participants (median(IQR) 13.3 (7.6-32.3). 10 (18%) participants showed mild impairment on the Montreal Cognitive Assessment (MoCA) (score&lt;26) (mean± SD 27.3±1.9). The test of premorbid functioning (TOPF) was high (116±8.8).

Discussion
Over 80% of patients were receptive to additional brain health screening during routine sleep assessments. There were fewer instances of mild impairment compared with recent literature (Beaudin 2021). The TOPF scores indicate high premorbid functioning that may be protective. Data collection will be continued including 12-month follow-up. Future analyses will explore quantitative sleep metrics, further cognitive domains and blood-based biomarkers of neurodegeneration which may detect early changes in this representative sleep clinic cohort.
O017 Investigating the role of amyloid burden on sleep microarchitecture and associations with cognitive functioning in individuals with OSA
Authors: Rawson G , Lam A , Cavuoto M , Barnes M , O’Donoghue F , Howard M , Robinson S , Rowe C , D’Rozario* A , Jackson* M 
Published: December 2024

Abstract

Background
Emerging evidence suggests obstructive sleep apnoea (OSA) is a risk factor for increased amyloid aggregation, a biomarker of Alzheimer’s disease, with disrupted sleep architecture hypothesised as a potential mechanism. Moreover, sleep architecture abnormalities observed in (OSA) may explain impaired cognition. However, the relationships between sleep microarchitecture, amyloid burden and cognition in OSA are unclear.

Methods
Thirty-four participants with OSA (age=57.7, 19 males), and 12 controls (age=57.1, 6 males) underwent diagnostic polysomnography (PSG), 11C-PiB positron emission tomography (PET) scan to quantify amyloid burden, and a cognitive assessment battery. All-night EEG recordings were processed and spectral power in slow oscillation (SO) and delta frequency ranges were calculated.

Results
Higher global amyloid burden was associated with lower delta power at O2 during slow wave sleep (SWS) in the OSA group (ß=-0.443, R2=0.142, p=0.048, controlled for age and non-REM AHI) and in the entire sample (ß=-.497, R2=.161, p=.019). Delta power and SO power in the OSA group was in turn associated with verbal memory (frontal regions - delta: ß=-0.811, p&lt;0.001 and SO: ß=-0.661, p=0.008; central - delta: ß=0.537, p=0.026; occipital - delta: ß=0.586, p=0.014 and SO: ß=0.526, p =0.043).

Discussion
Greater amyloid burden was associated with slow wave deficits in older people with and without OSA. Worse memory performance was associated with lower slow frequency activity in central and occipital brain regions but higher activity in frontal regions. It is possible that pathological EEG slowing in some brain regions may explain the differential associations between sleep neurophysiological measures and memory.
O019 Understanding sleep-wake disturbances in dementia with Lewy bodies using parametric and non-parametric measures in wrist actigraphy
Authors: Anderson J , Chiu N , Pye J , Grunstein R , Lewis S , Matar E 
Published: December 2024

Abstract

Introduction
Sleep-wake disturbances are a commonly reported non-motor symptom in dementia with Lewy bodies patients (DLB). Wrist actigraphy offers a low-burden, cost-effective option to measure sleep disturbances and has demonstrated alterations in rest-activity patterns in other synucleinopathies. This study reports both parametric and non-parametric actigraphy variables in DLB and investigates their associations with cognitive, behavioural, and quality of life measures.

Methods
Eleven participants with DLB (10:1, M:F) and 7 age-matched healthy controls (5:2, M:F) completed a battery of neuropsychological, cognitive and motor assessments and were given an actigraphy device for 2 weeks. Mann-Whitney U tests were used to compare groups and Spearman’s correlation was used to assess the relationship between actigraphy and cognitive, behavioural and quality of life measures.

Results
DLB patients reported lower cognitive (p=0.002), motor function (p&lt;0.001) and non-motor function scores (p=0.001), along with increased depression (p=0.014). There were no significant differences between groups for total sleep time or percentage of time awake. However, compared to controls, DLB patients reported higher interdaily variability (transitions between rest and activity) (p=0.015) and lower relative amplitude (the difference between the leave active 5-hour and most active 10-hour patterns in an average 24-hour period) (p=0.011). Furthermore, interdaily stability (the relationship between rest-activity rhythm and the zeitgeber) was positively correlated with depression, hallucinations, and cognitive fluctuations.

Discussion
Wrist actigraphy and its non-parametric measures may serve as a valuable tool for investigating sleep-wake disturbances in patients with DLB and help better understand the pathophysiological role of rest-activity and circadian rhythm disruption in this condition.
O023 Circadian Photoreception Influences Loss Aversion
Authors: Lander A , Burge M , Thomas B , Phillips A , McGlashan E , Cain S 
Published: December 2024

Abstract

Introduction
Gambling behaviour is a growing societal problem. While previous work has explored how sound encourages gambling, an unexplored element that may play a role is the impact of circadian photoreception on cognitive processes underlying this behaviour. This study investigated the influence of circadian photoreception on loss aversion in gambling by altering the blue content of light while maintaining the same visual brightness (200 lux).

Methods
Fifteen participants (5 male, M = 20.40, SD = 2.03) completed an economic decision-making task under blue-enriched and blue-depleted light on separate occasions. The task required participants to choose between a risky gamble of positive or negative value or a less risky guaranteed outcome. Hierarchical Bayesian Modelling derived individual parameter estimates for loss aversion and trial-by-trial performance was analysed using linear mixed models.

Results
Light condition significantly influenced loss aversion, with blue-enriched light associated with a.63 decrease in loss aversion (p &lt;.01). Significant sex differences were also found, with women displaying greater loss aversion across both light conditions.

Conclusions
This study presents evidence that light that preferentially targets circadian photoreception reduces loss aversion and suggests that reducing the blue light content in gambling scenarios may be a promising target for reducing gambling behaviour.
O031 The feasibility and efficacy of combined treatment for primary school-aged children with posttraumatic stress disorder and sleep disturbance
Authors: Rose C , Nixon R , Paterson J 
Published: December 2024

Abstract

Introduction
One in three primary school aged children will experience trauma, such as exposure to death, injury, or violence, with up to 77% reporting sleep disturbances. Trauma-focused cognitive behavioural therapy (TF-CBT) is the primary treatment but does not specifically address sleep issues. Adequate sleep is essential for consolidating adaptive safety beliefs and engaging in fear extinction. Without addressing sleep, treatments for posttraumatic stress disorder in children may be less effective. Treating sleep first can build rapport, improve memory consolidation and emotional regulation, and enhance engagement and confidence. Research in adults shows significant trauma symptom improvement following sleep treatments.

Methods
This study assesses the feasibility and efficacy of an integrated treatment for trauma-exposed children (5-12 years; n = 25) with sleep disturbances. The open trial includes 10 one-hour sessions and a 3-month follow-up. The first four sessions focus on CBT-I for sleep, followed by six TF-CBT sessions for trauma. Feasibility and efficacy will be evaluated using Bowen’s Feasibility Study Framework.

Results
Preliminary analysis of three participants after CBT-I (mid-treatment) shows a one-hour increase in total sleep time, but no significant change in PTSD symptoms. One participant who completed therapy showed significant symptom reduction on both the CBCL and CSHQ, with scores below the clinical cut-off post-treatment.

Conclusion
Initial findings suggest that CBT-I effectively increases total sleep time, though does not have an impact on PTSD symptoms. Further data collection and analysis with a larger sample size are necessary to substantiate these findings.
O037 Deep learning model of respiratory waveform prediction for an optogenetic therapy for obstructive sleep apnoea.n
Authors: Bull C , Kulaga T , Lovell N , Bilston L 
Published: December 2024

Abstract

Introduction
A novel therapeutic application of optogenetic stimulation as a treatment for Obstructive Sleep Apnea (OSA) requires stimulation of the pharyngeal muscles synchronously with the onset of inspiration to maintain airway patency during sleep1. A sensor array in a removable oral appliance was developed to monitor physiological data; photoplethysmography, acceleration, temperature and audio to predict respiratory airflow. This could then deliver correctly timed stimulation pulses coinciding with inspiration onset as part of a potential therapy.

Methods
Twenty participants underwent daytime respiratory monitoring (flow, volume and mask pressure) with concurrent monitoring using the oral sensor appliance. Participants were coached to perform multiple breathing patterns; spontaneous, fast and slow breathing, apneas, coughs and snores in supine, left and right-side sleeping positions. Sensor data was used to train a Long Short-Term Memory (LSTM) deep learning model against airflow data to predict respiration waveforms.

Results
A LSTM deep learning model was trained on over 24,000 seconds of physiological data from the 20 participants to predict respiratory waveforms. The model successfully predicted 5-second respiratory waveforms from the preceding 10 seconds of physiological data with acceptable accuracy (Mean Squared Error = 0.078, Root Mean Squared Error = 0.278), enabling real-time targeted optogenetic stimulation timing.

Discussion
This study establishes a proof of concept for using an oral sensory appliance in conjunction with optogenetic therapy for OSA. Furthermore, the sensor array demonstrates promise as a potential platform for vital sign and sleep monitoring within the oral cavity.
O040 Investigating the effects of airflow signal filtering on non-invasively quantified estimates of flow limitation
Authors: Mann D , Staykov E , Sands S , Terrill P 
Published: December 2024

Abstract

Introduction
We previously reported a method to estimate flow limitation (FL, range 0-~1) from the airflow signal recorded within a polysomnogram. This method utilised high quality nasal pressure signals, without high-pass (HP) filtering. However, many clinical recording systems implement HP filtering on airflow signals. We hypothesised that FL estimates would be adversely affected when airflow signals have HP filtering present.

Methods
Within our existing framework for estimating FL, we manipulated the airflow signal by applying digital HP filtering (Butterworth, 4th order) at commonly used cutoff frequencies (0.005, 0.01, 0.03, 0.1Hz). At each HP filter cutoff, performance was assessed at the breath-level (pooled, all patients) and patient-level (median, sleep only) using coefficient of determination (R²) and root mean squared error (RMSE) comparing FL estimates with HP filtering against reference data without HP filtering.

Results
In N=96 individuals, R² decreased while RMSE increased as HP filter cutoff increased. For HP filter cutoffs at 0.005, 0.01, 0.03 and 0.1Hz, breath-level R² was 0.923, 0.879, 0.740, and 0.483; while RMSE was 0.062, 0.079, 0.129, and 0.219, respectively. Similarly, patient-level R² was 0.994, 0.977, 0.843, and 0.738; while RMSE was 0.015, 0.030, 0.100, and 0.170.

Discussion
Increasing HP cutoff frequency resulted in a reduction of consistency of FL estimates when compared to those made using an unfiltered airflow signal. Further work including reference to ‘gold standard’ is required, however, in line with current AASM recommendation (“Direct current (DC) or ≤0.03Hz”), this study suggests HP filter cutoff frequency for nasal pressure should be minimised, preferably avoided.
O042 Parent-reported prevalence of sleep disordered breathing in Australian children with neurodevelopmental disorders
Authors: Anderson M , Vandeleur M , Waters K , Chawla J 
Published: December 2024

Abstract

Introduction
Sleep problems are a common yet complex issue for children with neurodevelopmental disorders (ND), affecting up to 80% of these individuals. The aetiology is multifactorial, including physiological, anatomical, psychological, and iatrogenic factors which contribute to problematic, and often persistent, sleep issues. Few studies have evaluated the prevalence of sleep disordered breathing (SDB) in a broad population of children with ND. This study aims to evaluate the parent-reported prevalence of SDB in children with ND.

Methods
As part of a multi-site, cross-sectional survey, caregivers of community-based and hospital-referred children with ND completed the paediatric sleep questionnaire (PSQ). PSQ was scored according to validated methods, including the subscales of snoring, sleepiness, and behaviour. Data were analysed, including stratification by age, sex, and ND type.

Results
There were 294 participants, with 261 PSQ responses available for analysis (54% male, median age 8.7yrs). 41.4% of children had a genetic syndrome, 24.1% autism spectrum disorder and attention deficit hyperactivity disorder, 16.5% neurological disorders, 13.4% undiagnosed/other ND and 4.6% unspecified. 74.7% of children had parent-reported SDB (PSQ&gt;0.33), with a mean/median PSQ score of 0.46±0.19. Snoring, sleepiness, and behavioural subscale scores were 0.27±0.34, 0.52±0.34, and 0.70±0.33 respectively.

Discussion
This study is the first to report on the prevalence of parent-reported symptoms of SDB in a large cohort of Australian children with ND. It demonstrates a high pretest probability of SDB with 75% of participants having a positive PSQ result. These findings highlight the importance of screening for SDB in children with ND to ensure early intervention.
O045 Repetitive transcranial magnetic stimulation improves sleep in children with autism spectrum disorder
Authors: Ezedinma U , Burgess S , Singh J , Jones E , Nikles J , Ladmas A , Campell G , Fjaagesund S , Swierkowski P , Metse A , Downer T , Oprescu F 
Published: December 2024

Abstract

Introduction
There are no controlled studies examining the impact of repetitive transcranial magnetic stimulation (α-rTMS) on sleep difficulties in children with autism spectrum disorder (ASD).

Method
Twenty children (6-12yrs old; 16 males) with ASD (level 2) and sleep difficulties were recruited and randomised into α-rTMS and waitlist control groups (1:1). The treatment group received ten sessions of α-rTMS. Sleep outcomes were assessed at baseline and immediately post-α-rTMS on the Children Sleep Habit Questionnaire (CSHQ).

Result
The total CSHQ score was significantly improved in the treatment group as compared to the waitlist control group (-12.6; 95% CI –22.3, –2.3; p= 0.015; d= -1.25). Bedtime resistance (-0.61; 95% CI –1.04, –0.19; p= 0.008; d= -1.418), sleep onset delay (-1.0; 95% CI –1.7, -0.3; p= 0.006; d=-1.4), and sleep duration (-0.6; 95% CI –0.19 to –0.9, p= 0.007, d= -1.5), all improved. The treatment group reported no adverse events.

Conclusion
Preliminary evidence suggests that α-rTMS is well-tolerated and improves sleep difficulties in children with ASD.
O049 Maintaining long-term functional optogenetic stimulation for OSA therapy in a rodent model
Authors: Knapman F , Cohen M , Rail K , Turner A , Swain R , Kulaga T , Lovell N , Lisowski L , Shklovskaya E , Burke P , Bilston L 
Published: December 2024

Abstract

Introduction
Obstructive sleep apnoea (OSA) patients are often sub-optimally treated due to poor tolerance and/or incomplete responses to established therapies. Our novel therapy sensitises upper airway muscles to light (optogenetics) and allows their activation during sleep. Previous work has demonstrated that an adeno-associated viral vector (AAV) driven by a muscle-specific promoter produces strong expression of light-sensitive proteins (opsins) in the tongue, and strong light-evoked muscle activation 3-weeks after administration. Here we determine whether this response persists over 12-weeks, and whether immunosuppression is required.

Methods
Rats received intralingual injections of the AAV. After 12-weeks, opsin expression in the tongue was quantified via confocal imaging. Light-evoked muscle activation was recorded in a model of sleep-associated muscle hypotonia. This was repeated in three additional groups of animals. Group 1 received rapamycin (4 mg/kg/day) and cyclosporin (5 mg/kg/day), group 2 received prednisolone (1 mg/kg/day, tapering 10%/week from week 9), and group 3 received daily vehicle intrapleural injections.

Results
Without immunosuppression, opsin expression decreased ~4-fold in the tongue between 3- and 12-weeks post-AAV administration (two-way RM ANOVA, p=0.01). Subsequently, light-evoked muscle-activation also declined (linear mixed model, time*stimulation, p&lt;0.001). With rapamycin/cyclosporin administration, light stimulation at 12-weeks was able to increase muscle-activation ~2-fold (p&lt;0.001). Prednisolone and vehicle administration did not facilitate light-evoked muscle-activation at 12-weeks (p&gt;0.05; LMM, group*stimulation p&lt;0.001).

Discussion
Rapamycin/cyclosporin administration allows persistent opsin expression and light-evoked muscle activation. As all existing clinically approved AAV-mediated gene therapies require initial immune suppression, this requirement is not a barrier to clinical translation of an optogenetics-based therapy for OSA.