Within-subjects Factor Research Articles

Exploring sex differences in auditory saliency: the role of acoustic characteristics in bottom-up attention

BackgroundSeveral cognitive functions are related to sex. However, the relationship between auditory attention and sex remains unclear. The present study aimed to explore sex differences in auditory saliency judgments, with a particular focus on bottom-up type auditory attention.MethodsForty-five typical adults (mean age: 21.5 ± 0.64 years) with no known hearing deficits, intelligence abnormalities, or attention deficits were enrolled in this study. They were tasked with annotating attention capturing sounds from five audio clips played in a soundproof room. Each stimulus contained ten salient sounds randomly placed within a 1-min natural soundscape. We conducted a generalized linear mixed model (GLMM) analysis using the number of responses to salient sounds as the dependent variable, sex as the between-subjects factor, duration, maximum loudness, and maximum spectrum of each sound as the within-subjects factor, and each sound event and participant as the variable effect.ResultsNo significant differences were found between male and female groups in age, hearing threshold, intellectual function, and attention function (all p > 0.05). Analysis confirmed 77 distinct sound events, with individual response rates of 4.0–100%. In a GLMM analysis, the main effect of sex was not statistically significant (p = 0.458). Duration and spectrum had a significant effect on response rate (p = 0.006 and p < 0.001). The effect of loudness was not statistically significant (p = 0.13).ConclusionsThe results suggest that male and female listeners do not differ significantly in their auditory saliency judgments based on the acoustic characteristics studied. This finding challenges the notion of inherent sex differences in bottom-up auditory attention and highlights the need for further research to explore other potential factors or conditions under which such differences might emerge.

Short and long-term impact of the frequency of social media influencers’ sponsored posts on attitudinal and behavioral brand outcomes

ABSTRACT The importance of Social Media Influencers (SMIs) as persuasive agents for companies has long been established. However, we need more research on the long-term (compared to the short-term) impact of the frequency of SMI’s advertising messages. We examine the effects of different frequency levels of SMI’s sponsored posts on brand outcomes, precisely brand attitude and purchase intention. Based on the concept of attitudinal persuasion knowledge, we examine the mediating role of skepticism. Moreover, we examine how brand outcomes change over time based on the Sleeper Effect. We conducted a 2 (between-subject factor: low vs. high frequency of sponsored-pots) by 2 (within-subject factor: short vs. long-term effect) experiment with N = 190 U.S. participants. The results show that the frequency of sponsored posts had no direct or indirect influence on brand outcomes in the short term, nor was skepticism activated. Brand attitudes did not change significantly in the long term, but purchase intention increased.

Office workers’ performance and satisfaction with the luminous environment under standard and daylight mimicking LEDs

The effects of illuminance and correlated colour temperature (CCT) on people's work performance, mood, and comfort have been previously investigated, but some aspects need to be deepened. In particular, CCT does not uniquely describe light spectral power distribution (SPD), hence it is not sufficient to define the effects of light on people's non-visual responses. This study aims to extend current knowledge about the acute effects of light on people's work performance, mood, and environmental appraisal by carrying out a 2x2 mixed design experiment where LEDs' SPD (standard and daylight-mimicking) is the within-subject factor and CCT (4000 K and 6500 K) is the between-subject factor. 40 participants, aged between 18 and 35, joined the experiment. It was found that SPD has significant effects on reaction time in selective attention and errors in working memory activities, being the performances under daylight-mimicking LEDs the best. Moreover, a lower number of errors in sustained attention and executive function was registered under 4000 K against 6500 K, but better performances occurred under 6500 K against 4000 K considering errors in selective attention and reaction speed in sustained attention. Regarding room appraisal, 4000 K was preferred over 6500 K and daylight-mimicking LEDs were preferred over the standard ones.

Effectiveness of TheraPEP Versus Conventional Breathing Techniques in Managing Acute COPD Exacerbations

Background: Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide, often complicated by acute exacerbations that impair lung function and quality of life. Effective airway clearance techniques are essential in managing exacerbations, but the comparative effectiveness of different methods remains unclear. This study aimed to evaluate the short-term effectiveness of TheraPEP, a positive expiratory pressure (PEP) device, versus the Active Cycle of Breathing Technique (ACBT) in managing acute COPD exacerbations. Methods: A randomized controlled trial (RCT) was conducted with 60 patients (≥40 years) admitted with acute exacerbations of COPD. Participants were randomly assigned to either the TheraPEP group (n=30) or the ACBT group (n=30). Each group received three daily sessions of their assigned therapy throughout their hospital stay. Primary outcomes included dyspnea, measured by the modified Borg Dyspnea Scale, and secondary outcomes included sputum clearance, lung function (FEV1, FVC, and FEV1/FVC ratio), oxygen saturation (SpO₂), and quality of life, measured by the Breathlessness, Cough, and Sputum Scale (BCSS). Data were collected at baseline, discharge, and 14-day follow-up. A two-way repeated-measures ANOVA was used to examine changes in dyspnea, lung function, sputum clearance, SpO₂, and BCSS scores over time (baseline, discharge, and 14-day follow-up) within and between groups. The main effects of time (within-subject factor) and group (between-subject factor) were assessed, along with the interaction effects (time × group). Results: Both groups demonstrated significant improvements in dyspnea, lung function, and quality of life from baseline to discharge and follow-up. However, the TheraPEP group showed significantly greater improvements in sputum clearance (p=0.01), oxygen saturation (p=0.03), and BCSS scores (p=0.03) compared to the ACBT group. No significant between-group differences were found for FEV1, FVC, or FEV1/FVC ratio (p &gt; 0.05). Conclusions: Both TheraPEP and ACBT are effective in managing acute COPD exacerbations, but TheraPEP offers additional benefits in terms of sputum clearance and oxygenation. These findings suggest that TheraPEP may be more suitable for patients with severe mucus hypersecretion. Further research is warranted to assess the long-term effects of these therapies on COPD progression and patient outcomes.

Assessing the influence of an android robot's persuasive behaviors and context of violation on compliance

This study investigates how the perception of persuasive behaviors (polite, logical, displeased, angry) of an android robot is affected by situations regarding the context of violation (affecting oneself or others), and by subject traits, such as compliance awareness (CA) and agreeableness (AG). We conducted a video-based experiment based on a mixed-subjects design with 98 participants from the US and conducted a three-way mixed analysis of variance to investigate the impact of persuasive types and situation types (as within-subject factors), and the subject trait groups (CA or AG, as between-subject factors), on the subjective impressions of the persuasive behaviors by the android robot. Results showed that more negative behaviors (anger and displeasure) are appraised as being more appropriate and effective to persuade a violator in situations where the violation affects others, while no clear preference was found in a situation where the violation affects only oneself. Regarding the subject traits, participants with higher CA and lower AG would be willing to adhere to any persuasive behaviors, while their counterparts would dislike being persuaded through negative behaviors by the robot. These findings can be considered in future studies to develop cognitive models for generating situation-aware behaviors in social robots.

Oxytocin Reduces Noradrenergic-Induced Opioid-Like Withdrawal Symptoms in Individuals on Opioid Agonist Therapy

BackgroundIntranasal administration of the neuropeptide oxytocin has been explored as a potential therapeutic agent for opioid use disorder (OUD). Oxytocin was effective in reducing stress and withdrawal symptoms in individuals with OUD. MethodThis phase 1 crossover, randomized, double-blind, placebo-controlled trial tested the safety, tolerability, and efficacy of intranasal oxytocin (80 international units) twice a day for 7 days in participants (n = 20) with OUD who were taking an opioid agonist therapy. In the laboratory, participants underwent opioid cue exposure paired with noradrenergic activation produced by yohimbine or placebo. Assessments included 1) subjective response: craving, withdrawal, anxiety, and stress; 2) biomedical markers: hypothalamic-pituitary-adrenal axis response (cortisol) and noradrenergic activation (α-amylase); and 3) safety measures: hemodynamics and adverse event evaluation. Generalized linear model with model-based estimator in the covariance matrix was used, with medication (oxytocin/placebo) and noradrenergic activation (yohimbine/placebo) as within-subject factors. ResultsOxytocin significantly reduced opioid-like withdrawal, anxiety symptoms, and cortisol levels elicited by cue exposure under noradrenergic activation produced by yohimbine. This effect was specific because oxytocin did not reduce craving, hemodynamics, or α-amylase levels increased by yohimbine administration. A single dose of yohimbine elicited the noradrenergic stimulation, and 7-day oxytocin administration was safe and well tolerated among individuals diagnosed with OUD and taking opioid agonist therapy. ConclusionThe findings of this study suggest that oxytocin alleviates opioid-like withdrawal symptoms and anxiety by modulating the hypothalamic-pituitary-adrenal axis.

Trust is Contagious: Social Influences in Human-Human-AI Team

When working in teams, individuals’ trust can be influenced by their teammates consciously or unconsciously through social interactions, a phenomenon defined in this paper as trust contagion. We investigated the effects of trust contagion in human-human-AI teams using a 2 (AI reliability: high vs. low, within-subjects factor) x 3 (confederate trusting: high, low, neutral, between-subjects factor) mixed-subject design. A team of three, consisting of one participant, one confederate, and one AI teammate, performed a ten-round trust-based game that requires resource allocation and joint decision making with their human and AI teammates. Results showed that when teaming up with high-trusting confederate, people showed higher trust in the AI teammate and performed better in the game. These findings suggest that social influences in human-human interactions can significantly affect human-AI trust, providing important theoretical implications for integrating AI in team settings.

Neurocognitive demands reducejump distance and coordination variability of the injured leg in athletes after anterior cruciate ligament reconstruction.

The study aimed to evaluate the impact of neurocognitive reliance on jump distance and lower extremity kinematics in individuals who had undergone anterior cruciate ligament reconstruction (ACLR). This was achieved by comparing hop performance under standard and neurocognitive conditions. Thirty-two patients after ACLR and 32 healthy controls (CTRL) participated. Both groups performed a single-leg hop for distance (SLHD) and two neurocognitive hop tests, each designed to evaluate distinct aspects of neurocognition. The neurocognitive tests included the reaction SLHD (R-SLHD), measuring reaction to a central stimulusand working memory SLHD (WM-SLHD) assessing response to a memorized stimulus amidst distractor stimuli. Distances were assessed for the three-hop tests. In addition, joint kinematics were collected to calculate lower extremity coordination of the lower extremity. SLHD performance was defined as the mean hop distance per condition per leg for each participant and was analyzed using a mixed ANOVA with condition and leg as the within-subjects factors and the group (ACLR or CTRL) as the between-subjects factor. Differences in joint coordination variability were analyzed using two-sample t-test statistical parametric mapping (SPM) with linear regression. The WM-SLHD resulted in a significantly decreased jump distance compared with the standard hop test both for ACLR and CTRL. Furthermore, the leg difference within the ACLR group increased under higher cognitive load as tested with the WM-SLHD, indicating leg-specific adaptations in lower extremity coordination. Neurocognitive single-leg hop tests resulted in reduced jump distance in CTRL and ACLR. The neurocognitive hop test revealed changes in coordination variability for the CTRL and the uninjured leg of ACLR individuals, whereas the injured leg's coordination variability remained unaltered, suggesting persistent cognitive control of movements post-ACLR. Level III.

Creativity in motion: examining the impact of meaningful movement on creative cognition

This study examined the link between creative cognition and meaningful physical movement among university students (N = 151) from a cognitive offloading perspective. A linear mixed model, repeated measures design examined whether divergent thinking on three Alternative Uses Tasks (AUTs; within-subjects factor) was influenced by movement in three independent experimental groups: (1) gesture as meaningful movement (n = 51), (2) meaningless movement (n = 50), and (3) restricted movement (n = 50). Linear mixed model results indicated that changes in AUT fluency, flexibility, and originality across trials did not significantly interact with group. However, baseline gesture frequency was positively associated with all four creativity outcome measures and moderated group-level changes in originality across trials. Infrequent baseline gesturers demonstrated lower originality scores in the gesture as meaningful movement group compared to those in the restricted movement group. More frequent baseline gesturers experienced higher originality in both the gesture as meaningful movement and meaningless movement groups compared to those in the restricted movement group. This study demonstrates that the cognitive processes involved in novel idea generation may be differentially impacted by movement and may be more sensitive to individual differences in movement predisposition than experimental movement manipulation.

Comparison of listening efforts in typically developing children and children with central auditory processing disorders

ObjectivesThe study's main objective was to compare Listening Effort (LE) in children with central auditory processing disorder [(C)APD] and typically developing children in quiet and at −2 and −6 dB SNR conditions. And to determine the relationship between LE and auditory processing abilities in children with (C)APD. MethodsThe study included 30 children (15 typically developing children and 15 diagnosed with (C)APD) aged 10–12 years. LE was measured using a dual-tasking paradigm. The primary task required the child to repeat the words. The second task required the child to click the mouse based on the image displayed on the laptop's screen. The primary task was done at quiet, −2 dB SNR, and −6 dB SNR conditions. LE was correlated with dichotic CV, duration pattern test, speech perception in noise - Indian English, and gap detection test in children with (C)APD. ResultsA mixed ANOVA was performed with LE in various conditions as the within-subject factor and group as the between-subject factor for both repetition and reaction time. The study found that LE repetition and reaction time had a significant main effect across conditions and groups. The correlation results revealed a significant relationship between LE reaction time with dichotic scores and GDT thresholds only at −2 dB SNR and −6 dB SNR conditions. There was no significant correlation between other auditory processing abilities and LE under different conditions, such as quiet, SPIN-IE, and DPT at −2 dB SNR and −6 dB SNR. ConclusionThe study emphasizes the importance of cognitive abilities for adequate listening comprehension in challenging situations. As a result, assessing LE in this population may provide additional information for developing therapeutic activities and assisting the child in overcoming listening difficulties.

Value of a quality label and European healthcare professionals' willingness to recommend health apps: An experimental vignette study.

This study aimed to evaluate healthcare professionals' (HCPs') willingness to recommend health apps presented with versus without the CEN-ISO/TS 82304-2 health app quality label. The study was an experimental vignette study describing 12 short hypothetical scenarios, with Label (absent vs present) as a between and Type of App (prevention vs self-monitoring vs healthcare) and Patient Socioeconomic Status (low vs high) as within-subjects factors. The main outcome measure was HCPs' willingness to recommend apps. A total of 116 HCPs took part in the study. A significant main effect of the label was found. Further, HCPs were most willing to recommend self-management apps and more willing to recommend apps to high as opposed to low SES patients. However, the effect of the label did not differ between apps or according to patients' SES. Results confirm that the quality label has potential for increasing willingness to changing HCPs' recommendation behavior.

Kinetics and Kinematics of the Push Press, Push Jerk, and Split Jerk.

Abstract Soriano, MA, Jiménez-Ormeño, E, Lake, JP, McMahon, JJ, Gallo-Salazar, C, Mundy, P, and Comfort, P. Kinetics and kinematics of the push press, push jerk, and split jerk. J Strength Cond Res 38(8): 1359–1365, 2024—The aim of this study was to explore the kinetics and kinematics across incremental loads with the push press (PP), push jerk (PJ), and split jerk (SJ). Eighteen resistance-trained men performed the 1 repetition maximum (1RM) tests (visit 1) 3–7 days before an incremental loading protocol (60, 75, and 90% 1RM) of the 3 exercises (visit 2). Kinetics and kinematics were derived from force-time data and compared using a repeated-measures analysis of variance with load and exercise as within-subject factors. Dependent variables for the biomechanics assessment were categorized as output (power and impulse), driver (force and work), and strategy (displacement and duration) metrics. The interrepetition reliability was assessed using the intraclass correlation coefficient and coefficient of variation. The PP, PJ, and SJ 1RM performance were 89.7 ± 15.4, 95.6 ± 14.4, and 103.0 ± 16.9 kg, respectively. Driver, strategy, and outcome metrics displayed moderate-to-excellent (intraclass correlation coefficient: 0.58–0.98) reliability with acceptable variability (% coefficient of variation: 2.02–10.00). Increased load resulted in significantly large increases in force, work, displacement, duration, power, and impulse (p &lt; 0.001, = 0.534–0.903). Exercise selection had a significant and large effect on power, impulse, work, and force (p &lt; 0.016, = 0.387–0.534). There was a significant and large effect of load × exercise interaction on work, displacement, and duration (p &lt; 0.019, = 0.158–0.220). Practitioners are encouraged to use heavier loads (90 &gt; 75 &gt; 60% 1RM) during the SJ exercise to maximize output, driver, and strategy kinetics and kinematics.

“I See Super-Rich (Versus Poor) People, Therefore I Spend”: Effects of Social Comparison and Donation Mode on Egoistic Spending versus Altruistic Giving

ABSTRACT Digital platforms present consumers with contrasting visual narratives, from images of opulence to depictions of poverty. This study delves into the strategic implications of such dichotomous exposures, anchored in Social Comparison Theory. Three experiments (∑ N = 1665) investigated how portrayals of affluence and deprivation influence audience behaviors, specifically egoistic luxury spending versus altruistic charitable giving. Experiment 1a employed a 2 (exposure to photos of poverty versus affluence) x 2 (luxury spending versus charitable giving scenario as the within-subjects factor) mixed factorial design. Experiment 1b employed a 2 (poverty versus affluence) x 2 (luxury spending versus charitable giving) between-subjects factorial design. Experiment 2 employed a 3 (poverty versus affluence versus neutral photos) x 2 (anonymized versus publicized donation) between-subjects factorial design to further examine the interaction effects of social comparison direction and donation mode. Empirical findings highlight that downward social comparison (exposure to poverty) can amplify charitable inclinations, while upward comparison (exposure to affluence) can enhance conspicuous consumption. Individual difference factors such as materialism, need for status, social comparison orientation, and greed play pivotal roles in moderating these effects. This research contributes to the understanding of digital portrayal influences on consumers’ spending behavior, offering both theoretical insights and practical implications for strategic communication.

Blunted stimulus-preceding negativity during reward anticipation in major depressive disorder

BackgroundReward processing dysfunction is a core characteristic of major depressive disorder (MDD), yet event-related potential (ERP) research in MDD has predominantly focused on reward receipt as opposed to anticipation. The stimulus-preceding negativity (SPN) ERP reflects anticipatory brain processing. This study examines whether individuals with MDD exhibit deficits during reward anticipation as evidenced by altered SPN amplitude. MethodsWe assessed prefeedback-SPN amplitudes during a monetary incentive delay (MID) task in individuals with MDD (n = 142, 99 with comorbid anxiety disorders [MDD + ANX]) compared to Controls (n = 37). A mixed analysis of variance was performed on prefeedback-SPN amplitude and behavioral measures, with group (MDD, MDD + ANX, Control) as the between-subjects factor, and feedback (gain, loss) and electrode (F3, F4, Fz, C3, C4, Cz, P3, P4, Pz) as within-subjects factors. ResultsA group main effect revealed faster reaction times for the Control group than MDD and MDD + ANX groups. A group x feedback interaction indicated that the MDD subgroup had smaller prefeedback-SPN amplitudes than MDD + ANX and Control groups when anticipating gain feedback. Additionally, individuals with current MDD, irrespective of past MDD and comorbid anxiety, exhibited smaller SPN amplitudes than Controls prior to gain feedback. LimitationsThe MID paradigm, designed for functional magnetic resonance imaging (fMRI) data acquisition, lacks optimization for ERP analysis. Moreover, the clinical groups included more females than the Control group. ConclusionsReduced resource allocation to reward anticipation may differentiate MDD from MDD + ANX and Control groups. Further investigation of the neural mechanisms of distinct MDD phenotypes is warranted.

Training benefits driver behaviour while using automation with an attention monitoring system

Attention, or more generally, driver monitoring systems have been identified as a necessity to address overreliance on driving automation. However, research suggests that monitoring systems may not be sufficient to support safe use of advanced driver assistance systems (ADAS), also evidenced by a recent major recall of Tesla’s monitoring software. The objective of the current study was to investigate whether different training approaches improve driver behaviour while using ADAS with an attention monitoring system. A driving simulator study was conducted with three between-subject groups: no training, limitation-focused training (highlighted situations where ADAS would not work), and responsibility-focused training (highlighted the driver’s role/responsibility while using ADAS). All participants (N = 47) experienced eight events which required the ego-vehicle to slow down to avoid a collision. Anticipatory cues in the environment indicated the potential for the upcoming events. Event type (covered in training vs. not covered) and event criticality (action-necessary vs. action-not-necessary) were within-subject factors. The responsibility-focused group made fewer long glances (≥ 3 s) to a secondary task than the no training and limitation-focused groups when there were no anticipatory cues. Responsibility-focused training and no training were associated with faster takeover time at the events than limitation-focused training. There were additional benefits of responsibility-focused training for events that were covered in training (e.g., higher percent of time looking at the anticipatory cues). Overall, our results suggest that even if attention monitoring systems are implemented, there may be benefits to driver ADAS training. Responsibility-focused training may be preferable to limitation-focused training, especially for situations where minimizing training length is advantageous.

Speed and contextual information of a crime-related video bias the responsibility judgments

Courts often rely on video evidence, assuming it accurately shows important legal details. Yet, studies suggest that video isn’t inherently “objective” and people, including legal professionals, might misinterpret its objectivity due to video quality or context. This study aimed to explore how video speed variations and contextual information affect judgments of responsibility in a video portraying a bus assault. The study employed a 5 × 3 mixed design, with video speed (Very Slow, 0.88x; Slow, 0.96x; Neutral, 1.00x; Fast, 1.04x; Very Fast, 1.12x) as a between-subject variable, contextual information (Hit, Harm, Kill) attributed to the perpetrator’s action as a within-subject factor, and dimensions of accountability, predictability, criminal intent, and severity as dependent variables. ANOVA results from a sample of 300 participants (60 per video speed condition) revealed that the highest levels of accountability, criminal intent, and predictability were attributed when the contextual information was “hit” as compared to the “harm” and “kill” actions. Furthermore, the greatest difference in accountability and criminal intent scores for the kill action was between the very fast and very slow conditions. These findings raise significant concerns about the use of video evidence in criminal proceedings, as video speed manipulation and contextual information can have a substantial impact on responsibility judgments.

An ecological dynamics approach to promote physical literacy and well-being of primary school children: a cluster randomised controlled trial study protocol

BackgroundLittle is known about the impact of an ecological dynamics (ED) intervention (EDI) on primary school children’s physical literacy and well-being in the Hong Kong context. The aim of this...

Overt Word Reading and Visual Object Naming in Adults with Dyslexia: Electroencephalography Study in Transparent Orthography.

The study aimed to investigate overt reading and naming processes in adult people with dyslexia (PDs) in shallow (transparent) language orthography. The results of adult PDs are compared with adult healthy controls HCs. Comparisons are made in three phases: pre-lexical (150-260 ms), lexical (280-700 ms), and post-lexical stage of processing (750-1000 ms) time window. Twelve PDs and HCs performed overt reading and naming tasks under EEG recording. The word reading and naming task consisted of sparse neighborhoods with closed phonemic onset (words/objects sharing the same onset). For the analysis of the mean ERP amplitude for pre-lexical, lexical, and post-lexical time window, a mixed design ANOVA was performed with the right (F4, FC2, FC6, C4, T8, CP2, CP6, P4) and left (F3, FC5, FC1, T7, C3, CP5, CP1, P7, P3) electrode sites, within-subject factors and group (PD vs. HC) as between-subject factor. Behavioral response latency results revealed significantly prolonged reading latency between HCs and PDs, while no difference was detected in naming response latency. ERP differences were found between PDs and HCs in the right hemisphere's pre-lexical time window (160-200 ms) for word reading aloud. For visual object naming aloud, ERP differences were found between PDs and HCs in the right hemisphere's post-lexical time window (900-1000 ms). The present study demonstrated different distributions of the electric field at the scalp in specific time windows between two groups in the right hemisphere in both word reading and visual object naming aloud, suggesting alternative processing strategies in adult PDs. These results indirectly support the view that adult PDs in shallow language orthography probably rely on the grapho-phonological route during overt word reading and have difficulties with phoneme and word retrieval during overt visual object naming in adulthood.

Nocturnal Heart Rate Response to Spontaneous Arousals Following Sleep Restriction

Short sleep duration is associated with future cardiovascular disease including hypertension, especially in females, but mechanistic evidence is largely lacking. Experimental sleep restriction has been shown to cause short sleep-mediated tachycardia and reduced heart rate variability, indicative of autonomic cardiac instability, in some but not all studies. Heart rate (HR) response to spontaneous cortical arousals can be regarded as an index of autonomic cardiac control given its characteristic temporal pattern. Whether the HR response to cortical arousals is altered during experimental sleep restriction remains unknown. We hypothesized that sleep restriction would result in augmented HR reactivity to spontaneous arousals, and that this response would be more marked in females. We studied 19 young, healthy subjects (eight females, age: 23.5 ± 5 years, body mass index [BMI]: 24.5 ± 3.6 kg/m2). In a randomized, crossover design, participants were tested during a normal sleep (NS, 9 hr sleep opportunity) or sleep restriction (SR, 4 hr sleep opportunity) study arm. Each 16-day study visit consisted of a 4-day study acclimation phase, 9-day experimental sleep perturbation segment, followed by a 3-day recovery period. An overnight polysomnography (PSG) study was conducted on study days 2, 5 and 11 (at baseline and after 1 and 7 days of restricted versus control sleep). A registered PSG technician provided sleep staging and spontaneous arousal scoring, which was confirmed by an investigator with sleep expertise (IMG). For each identified spontaneous arousal, the HR change was quantified for 30 cardiac cycles post-arousal onset and compared to a pre-arousal baseline (average HR 5 – 10 cardiac cycles prior to arousal). An arousal was considered valid for analysis if at least one minute of stage N2 or rapid eye movement (REM) sleep occurred following sleep stage transition and was at least 30 seconds apart from other sleep disturbance-related events (e.g., limb movement, apneic event, etc.). Given low prevalence of slow wave sleep (SWS) arousals, arousals occurring in that sleep stage were excluded from present analysis. Statistical analysis, including repeated measures ANOVA (RMANOVA, p &lt; 0.05) with condition and time (cardiac cycles) as within-subjects factors and sex as the between-subjects factor, was conducted to compare the beat-to-beat HR response to arousal between study conditions. Additionally, average and peak HR responses to spontaneous arousals were compared via RMANOVA with condition and time (study days) as within-subjects and sex as between-subjects factors. HR response to spontaneous arousal in stage two and REM sleep was similar between NS and SR on study day 5 or day 11 (condition × time: p = 0.943, 0.865). Secondary analysis of average and peak HR responsiveness to spontaneous arousals in stage two and REM sleep between conditions and study days was also not statistically different (condition × time: p = 0.193, 0.185). Last, no significant sex differences were detected across comparisons (condition × time × sex: p &gt; 0.05 for all). These findings suggest that a 9-day sleep restriction paradigm may not alter cardiac autonomic function in otherwise healthy adults. Future work is warranted to determine whether these results extend to individuals with established cardiovascular risk factors or cardiovascular disease. Support: NIH T32-DK007013, R01-114676, and CTSA grant UL1-TR002377. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Evening and Morning-After Aortic Wave Reflection Responses to Binge Alcohol Consumption

Binge alcohol consumption acutely increases blood pressure and disrupts sleep. Recently, sleep irregularity has been linked to increases in aortic blood pressure. Increases in aortic wave reflection (i.e., aortic augmentation index) are associated with hypertension and cardiovascular risk. The purpose of the present study was to investigate the acute and next morning effects of evening binge alcohol consumption on aortic wave reflection. We tested the hypothesis that aortic augmentation index normalized to 75 heart beats per minute (AIx@75) and aortic pulsatile load (APL) would be increased acutely after binge drinking in the evening (study 1), and also the morning-after binge drinking compared to the morning after fluid control (study 2). Participants (n=33; 52% women; age 25±1 years; BMI 27±1 kg/m2) arrived at the laboratory at 4:00pm for baseline blood pressure and SphygmoCor (CPVH, Sydney, Australia) measures, and were provided a standardized meal verified by a registered dietitian. In a randomized order, separated by one month, participants completed a binge alcohol protocol (4-5 alcoholic drink equivalents within 2 hours) or fluid control. Alcohol or fluid control doses were administered in two equal allocates at 8 and 9 pm, and participants were provided 15 min to consume during each period. Binge alcohol consisted of a 1:3 mixture of 190 proof grain ethanol and fruit juice (i.e., Orange or Cranberry Juice) based on body weight and sex (1g/kg men, 0.85g/kg women), while the fluid control was only fruit juice in equal volume. Study 1 examined blood pressure, heart rate, aortic pulse pressure, APL, and AIx@75 before the standardized meal and then thirty minutes post-consumption of each allocated beverage using repeated measures ANOVA with condition (alcohol vs. fluid control) and time (baseline, post-drink 1, and post-drink 2) as within-subjects factors. Study 2 examined the same variables as study 1, but within 15 minutes of waking the morning after binge alcohol or fluid control using paired T-tests. Means were considered significantly different when p&lt;0.05. In study 1, fluid control decreased HR and APL after doses one and two, while HR and APL were increased after the second dose of alcohol (time x cond. p&lt;0.001). In study 2, morning-after HR was increased with binge alcohol compared to fluid control (57±1 vs. 63±2 beats/min; p&lt;0.001). Morning-after APL (1857±66 vs. 2060±82 a.u.; p=0.012) and AIx@75 (2.9±2.5 vs. 6.5±2.4%; p=0.042) were also elevated in the binge alcohol condition. Our results indicate binge alcohol consumption acutely increases HR and APL the evening of consumption and increases HR, APL, and AIx@75 the morning after. These findings highlight a potential key physiological contributor to the known associations between binge alcohol consumption and cardiovascular risk. NIH (AA-024892). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.