Partial Sleep Deprivation Attenuates the Positive Affective System: Effects Across Multiple Measurement Modalities

Evaluation of a daily facial massage on perceived sleep quality and well-being: A pilot study

OBJECTIVE

Sleep disorders are widespread and constitute a major public health risk. The present study thus aims to investigate the effect of a facial cosmetic self-massage daily routine on women's sleep and well-being.

METHODS

The present pilot study was conducted on 62 middle-aged women declaring daily tiredness and sleep troubles. We examined the effect of a regular facial cosmetic self-massage routine on sleep patterns, daytime sleepiness, and well-being over the course of 2 months.

RESULTS

After 1 and 2 months, our results show improved sleep quality (Pittsburgh Sleep Quality Index, PSQI - -20.2% after 2 months), reduced daytime sleepiness (Epworth Sleepiness Scale, ESS, -31.2% after 2 months), and increased well-being measures. The number of participants with abnormal sleep (PSQI >5) decreased over the course of the experiment as well, from 71.9% to 49.2% at the end of the 2 months [odds ratio 95% CI for decrease: 0.38 (0.18-0.81)]. Similarly, the number of participants with excessive daytime sleepiness (>10 on the ESS) decreased over the course of the study from 44.3% to 21% after 1 month [95% CI: 0.33 (0.15-0.73)] and to 16.1% after 2 months [95% CI: 0.24 (0.10-0.56)].

CONCLUSIONS

These results suggest that a facial cosmetic self-massage routine may improve sleep patterns and is likely to be a useful addition to a standard sleep hygiene routine.

Psychophysical changes after total sleep deprivation and experimental muscle pain

Sleep disturbances exacerbate chronic pain, increase psychological load, and increase inflammation. Delayed onset muscle soreness (DOMS) mimics aspects of chronic pain, predominantly affecting peripheral pain mechanisms, while experimental sleep provocations have been shown to impact central pain mechanisms. This study aimed to combine a DOMS model with total sleep deprivation (TSD) to create a novel model affecting both peripheral and central pain mechanisms. A total of 30 healthy participants attended two sessions (baseline and follow-up) separated by 24 h of TSD and a home rating after 48 h. Assessments of interleukin 6 (IL-6) levels, sleep quality, pain catastrophising, affect, and symptoms of depression and anxiety were included in the baseline and follow-up sessions. Additionally, pressure pain and tolerance thresholds, temporal summation, and conditioned pain modulation (CPM) were assessed using cuff-pressure algometry in the baseline and follow-up sessions. DOMS was induced with eccentric calf raises during the baseline session followed by 24 h of TSD. At follow-up pain tolerance (p = 0.012) was significantly reduced, and CPM (p = 0.036) was significantly impaired compared to baseline. Psychological changes included decreases in pain catastrophising (p = 0.027), positive affect (p < 0.001), negative affect (p = 0.003), and anxiety (p = 0.012). Explorative regression models predicted 58% and 68% of DOMS pain intensity after 24 and 48 h, respectively, based on baseline body mass index, pain thresholds, psychological measures, and IL-6 (p < 0.01). Combining DOMS with 1 night of TSD induced pain hypersensitivity, impaired CPM, and altered psychological states. A combination of baseline inflammation, psychological measures, and pain sensitivity significantly predicted DOMS pain intensity after 24 and 48 h.

The dynamic responses of mood and sleep physiology to chronic sleep restriction and subsequent recovery sleep

Healthy sleep of sufficient duration preserves mood and disturbed sleep is a risk factor for a range of psychiatric disorders. As adults commonly experience chronic sleep restriction (SR), an enhanced understanding of the dynamic relationship between sleep and mood is needed, including whether susceptibility to SR-induced mood disturbance differs between sexes. To address these gaps, data from N = 221 healthy adults who completed one of the two multi-day laboratory studies with identical 9-day SR protocols were analyzed. Participants randomized to the SR (n = 205) condition underwent 5 nights of SR to 4 hours of time-in-bed and were then randomized to one of the seven sleep doses that ranged from 0 to 12 hours in 2 hours increments; participants randomized to the control (n = 16) condition received 10 hours time-in-bed on all study nights. The Profile of Mood States (POMS) was used to assess mood every 2 hours during wakefulness and markers of sleep homeostasis (EEG slow-wave activity (SWA)) were derived via polysomnography. Mood progressively deteriorated across SR with marked disturbances in somatic mood components. Altered sleep physiology contributed to mood disturbance whereby increased EEG SWA was associated with increased POMS Total Mood Disturbance scores, a finding specific to males. The mood was restored in a dose-response fashion where improvements were greater with longer sleep doses. These findings suggest that when lifestyle and environmental factors are inhibited in the laboratory, the affective consequences of chronic sleep loss are primarily somatic mood disturbances. Altered sleep homeostasis may contribute to mood disturbance, yet sleep-dependent mechanisms may be sex-specific.

FPJA-Net: A Lightweight End-to-End Network for Sleep Stage Prediction Based on Feature Pyramid and Joint Attention

Sleep staging is the most crucial work before diagnosing and treating sleep disorders. Traditional manual sleep staging is time-consuming and depends on the skill of experts. Nowadays, automatic sleep staging based on deep learning attracts more and more scientific researchers. As we know, the salient waves in sleep signals contain the most important information for automatic sleep staging. However, the key information is not fully utilized in existing deep learning methods since most of them only use CNN or RNN which could not capture multi-scale features in salient waves effectively. To tackle this limitation, we propose a lightweight end-to-end network for sleep stage prediction based on feature pyramid and joint attention. The feature pyramid module is designed to effectively extract multi-scale features in salient waves, and these features are then fed to the joint attention module to closely attend to the channel and location information of the salient waves. The proposed network has much fewer parameters and significant performance improvement, which is better than the state-of-the-art results. The overall accuracy and macro F1 score on the public dataset Sleep-EDF39, Sleep-EDF153 and SHHS are 90.1%, 87.8%, 87.4%, 84.4% and 86.9%, 83.9%, respectively. Ablation experiments confirm the effectiveness of each module.

Effects of Savoring Meditation on Positive Emotions and Pain-Related Brain Function: A Mechanistic Randomized Controlled Trial in People With Rheumatoid Arthritis

Positive emotions are a promising target for intervention in chronic pain, but mixed findings across trials to date suggest that existing interventions may not be optimized to efficiently engage the target. The aim of the current pilot mechanistic randomized controlled trial was to test the effects of a positive emotion-enhancing intervention called Savoring Meditation on pain-related neural and behavioral targets in patients with rheumatoid arthritis. Participants included 44 patients with a physician-confirmed diagnosis of rheumatoid arthritis (n = 29 included in functional magnetic resonance imaging (fMRI) analyses), who were randomized to either Savoring Meditation or a Slow Breathing control. Both meditation interventions were brief (four 20-minute sessions). Self-report measures were collected pre-and post-intervention. An fMRI task was conducted at post-intervention, during which participants practiced the meditation technique on which they had been trained while exposed to non-painful and painful thermal stimuli. Savoring significantly reduced experimental pain intensity ratings relative to rest (P < .001). Savoring also increased cerebral blood flow in the ventromedial prefrontal cortex and increased connectivity between the ventromedial prefrontal cortex and caudate during noxious thermal stimulation relative to Slow Breathing (z = 2.3 voxelwise, false discovery rate cluster corrected P = .05). Participants in the Savoring condition also reported significantly increased positive emotions (ps < .05) and reduced anhedonic symptoms (P < .01) from pre- to post-intervention. These findings suggest that Savoring recruits reward-enhancing corticostriatal circuits in the face of pain, and future work should extend these findings to evaluate if these mechanisms of Savoring are associated with improved clinical pain outcomes in diverse patient populations. PERSPECTIVE: Savoring Meditation is a novel positive emotion-enhancing intervention designed for patients with chronic pain. The present findings provide preliminary evidence that Savoring Meditation is acutely analgesic, and engages neural and subjective emotional targets that are relevant to pain self-management. Future work should evaluate the clinical translation of these findings.

Sleep Disruption Moderates the Daily Dynamics of Affect and Pain in Sickle Cell Disease

Persons with sickle cell disease (SCD) often experience pain that can interfere with quality of life and daily activities. Pain can modulated by affect and sleep continuity; however, few studies have explored how these factors complementarily influence pain in adults with SCD. The study aims were to investigate 1) whether pain levels were heightened on days characterized by low positive affect and high negative affect, and 2) whether the relationship between affect and pain was intensified following nights of disrupted sleep. Adults with SCD (N = 25) completed ecological momentary assessments and daily sleep diaries. Mixed models were used to analyze the main and interactive effects of daily affect (positive affect and negative affect) and sleep disruption (wake after sleep onset and frequency of awakenings) on both daily average pain and daily maximum pain. Results suggested that daily average pain and maximum pain tended to be higher on days of low positive affect and high negative affect. Furthermore, the frequency of nocturnal awakenings moderated the relationship between positive affect and pain. On days where there were higher frequencies of nocturnal awakenings, low positive affect was associated with both average and maximum pain; however, this association was not observed with lower frequencies of nocturnal awakenings. The association between negative affect and maximum pain was also stronger at higher levels of awakenings. Results highlight the relevance of adjunctive interventions that target affect among populations with SCD and further suggest that sleep continuity may further facilitate these interventions, highlighting the importance of multimodal treatments. PERSPECTIVE: This study examined the effects of affect and sleep on pain among adults with sickle cell disease (SCD). Higher pain occurred on days of low positive affect and high negative affect, particularly following nights of more frequent awakenings. These findings emphasize the importance of addressing affect and sleep in SCD treatment.

Association Between Sleep Quality and Deep Learning-Based Sleep Onset Latency Distribution Using an Electroencephalogram

To evaluate sleep quality, it is necessary to monitor overnight sleep duration. However, sleep monitoring typically requires more than 7 hours, which can be inefficient in termxs of data size and analysis. Therefore, we proposed to develop a deep learning-based model using a 30 sec sleep electroencephalogram (EEG) early in the sleep cycle to predict sleep onset latency (SOL) distribution and explore associations with sleep quality (SQ). We propose a deep learning model composed of a structure that decomposes and restores the signal in epoch units and a structure that predicts the SOL distribution. We used the Sleep Heart Health Study public dataset, which includes a large number of study subjects, to estimate and evaluate the proposed model. The proposed model estimated the SOL distribution and divided it into four clusters. The advantage of the proposed model is that it shows the process of falling asleep for individual participants as a probability graph over time. Furthermore, we compared the baseline of good SQ and SOL and showed that less than 10 minutes SOL correlated better with good SQ. Moreover, it was the most suitable sleep feature that could be predicted using early EEG, compared with the total sleep time, sleep efficiency, and actual sleep time. Our study showed the feasibility of estimating SOL distribution using deep learning with an early EEG and showed that SOL distribution within 10 minutes was associated with good SQ.

The effect of experimental emotion induction on experimental pain: a systematic review and meta-analysis

ABSTRACT

The idea that emotions can influence pain is generally recognized. However, a synthesis of the numerous individual experimental studies on this subject is lacking. The aim of the present systematic review and meta-analysis was to synthesize the existing evidence on the effect of experimental emotion induction on experimental pain in nonclinical adults. PsycInfo and PubMed were searched up until April 10, 2023, for studies assessing differences in self-reported pain between emotion induction groups and/or control groups or between conditions within group. Risk of bias was assessed for the individual studies. The literature search yielded 78 relevant records of 71 independent studies. When compared with control conditions, the pooled results revealed a statistically significant pain-attenuating effect of positive emotion induction (between-group: Hedges g = -0.48, 95% CI: -0.72; -0.25, K = 9; within-group: g = -0.24, 95% CI: -0.32; -0.15, K = 40), and a statistically significant pain-exacerbating effect of negative emotion induction in within-group analyses but not between-group analyses (between-group: g = -0.29, 95% CI: -0.66; 0.07, K = 10; within-group: g = 0.14, 95% CI: 0.06; 0.23, K = 39). Bayesian meta-analysis provided strong support for an effect of positive emotion induction but weak support for an effect of negative emotion induction. Taken together, the findings indicate a pain-attenuating effect of positive emotion induction, while the findings for negative emotion induction are less clear. The findings are discussed with reference to theoretical work emphasizing the role of motivational systems and distraction for pain. Limitations include considerable heterogeneity across studies limiting the generalizability of the findings.

The Impact of Sleep Disturbances on Endogenous Pain Modulation: A Systematic Review and Meta-Analysis

The bidirectional relationship between sleep and pain problems has been extensively demonstrated but despite all the accumulating evidence, their shared mechanisms are currently not fully understood. This review examined the association between sleep disturbances, defined as a broad array of sleep-related outcomes (eg, poor quality, short duration, insomnia), and endogenous pain modulation (EPM) in healthy and clinical populations. Our search yielded 6,151 references, and 37 studies met the eligibility criteria. Qualitative results showed mixed findings regarding the association between sleep disturbances and temporal summation of pain (TSP) and conditioned pain modulation (CPM), with poor sleep more commonly associated with decreased pain inhibition in both populations. Quantitative results indicated that such associations were not statistically significant, neither in healthy populations when EPM outcomes were assessed for changes pre-/post-sleep intervention (TSP: .31 [95%CI: -.30 to .92]; P = .321; CPM: .40 [95%CI: -.06 to .85] P = .088) nor in clinical populations when such association was assessed via correlation (TSP: -.00 [95%CI: -.22 to .21] P = .970; CPM: .12 [95%CI: -.05 to .29]; P = .181). For studies that reported results by sex, meta-analysis showed that experimental sleep disturbances impaired pain inhibition in females (1.43 [95%CI: .98-1.88]; P < .001) but not in males (-.30 [95%CI: -2.69 to 1.60]; P = .760). Only one study investigating the association between sleep disturbances and offset analgesia was identified, while no studies assessing spatial summation of pain were found. Overall, this review provides a comprehensive overview of the association between sleep disturbances and EPM function, emphasizing the need for further investigation to clarify specific mechanisms and phenotypic subtypes. PERSPECTIVE: This review shines a light on the association between sleep disturbances and endogenous pain modulation function. Qualitatively, we found a frequent association between reduced sleep quality and impaired pain inhibition. However, quantitatively such an association was not corroborated. Sex-specific effects were observed, with females presenting sleep-related impaired pain inhibition but not males.

Chronotype and Affective Response to Sleep Restriction and Subsequent Sleep Deprivation

Prior research indicates that sleep restriction, sleep deprivation, and circadian misalignment diminish positive affect, whereas effects on negative affect are inconsistent. One potential factor that may influence an individual's affective response to sleep restriction, sleep deprivation, and circadian misalignment is chronotype. Later chronotypes generally report higher negative affect and lower positive affect under typical sleep conditions; however, there is mixed evidence for an influence of chronotype on affective responses to sleep restriction and sleep deprivation. The present study examined the effect of chronotype on positive and negative affect during sleep restriction and subsequent total sleep deprivation. Sixteen healthy adults (Mage = 28.2 years, SDage = 11.6 years) were classified as earlier or later chronotypes using multiple chronotype definitions: morningness-eveningness (MEQ), mid-sleep on free days corrected (MSFsc), habitual mid-sleep timing, dim light melatonin onset (DLMO), and phase relationship between DLMO and bedtime. Participants completed a 10-day protocol with one night of sleep restriction and subsequent 28 h total sleep deprivation. Affect was assessed hourly during scheduled wakefulness with the Positive and Negative Affect Schedule (PANAS). Data were analyzed with mixed-model analyses of variance (ANOVAs). During sleep restriction and subsequent sleep deprivation, positive affect decreased and negative affect increased. Across all chronotype measures, relatively later chronotypes demonstrated vulnerability to increased negative affect during sleep loss. The influence of chronotype on positive affect during sleep loss varied by chronotype measure. These findings suggest later chronotypes are more vulnerable to affective impairments during sleep loss and circadian misalignment, even when late chronotype is not extreme.

Sleep-EEG in comorbid pain and insomnia: implications for the treatment of pain disorders

Introduction

Patients with chronic pain experience a high prevalence of comorbid insomnia, which is associated with functional impairment. Recent advances in sleep electroencephalography (sleep-EEG) may clarify the mechanisms that link sleep and chronic pain. In this clinical update, we outline current advancements in sleep-EEG assessments for pain and provide research recommendations.

Results

Promising preliminary work suggests that sleep-EEG spectral bands, particularly beta, gamma, alpha, and delta power, may create candidate neurophysiological signatures of pain, and macro-architectural parameters (e.g., total sleep time, arousals, and sleep continuity) may facilitate EEG-derived sleep phenotyping and may enable future stratification in the treatment of pain.

Conclusion

Integration of measures obtained through sleep-EEG represent feasible and scalable approaches that could be adopted in the future. We provide research recommendations to progress the field towards a deeper understanding of their utility and potential future applications in clinical practice.

The impact of shift work on pain recognition, a robust ability among intensive care nurses

BACKGROUND

Pain empathy is essential for high-quality of care. The cognitive ability to identify and understand the pain in others remains underexplored in the context of hospital shift work. This study aimed to observe the early subliminal ability to detect pain in other faces and to investigate pain intensity evaluations during day and night shifts.

METHODS

Twenty-one nurses (31 ± 7 years, 20 women) from cardio-paediatric intensive care participated in this study. Eighteen nurses completed all testing in the morning and evening hours, before and after the 12-hour day and night shift. In the first test, the nurses had to decide if facial stimuli presented subliminally showed pain or not. During the second test, they consciously determined the intensity of the painful faces on a numerical scale. Sleep, sleepiness and empathy were also measured.

RESULTS

Recognition accuracy and pain sensitivity remained stable over time, only sensitivity increased following the work shift (F(1,15) = 7.10, p = 0.018). Intensity ratings remained stable. Sleepiness at the end of the night shift was negatively correlated with accuracy (ρ = -0.51, p = 0.018) and positively correlated with prior night shifts (ρ = -0.50, p = 0.022).

CONCLUSION

The judgement of facial pain expressions seems robust across shift types, only individual factors such as sleepiness interfere with pain recognition. Pain sensitivity may be enhanced during working hours.

SIGNIFICANCE STATEMENT

Some professions need to know how to assess pain 24/7 and a lack of sleep can disrupt the cognitive processes necessary for this assessment. Night shifts provoke a bias in pain management, and sleep deprivation, a decrease in pain evaluation. By conducting a repeated measure study in the field that applied a different paradigm (subliminal recognition of facial cues) we add evidence to the understanding of pain recognition and the impact of sleep deprivation on the early processing of pain in others.

Vulnerability to sleep-related affective disturbances? A closer look at dysfunctional beliefs and attitudes about sleep as a moderator of daily sleep-affect associations in young people

STUDY OBJECTIVES

Sleep and affect are closely related. Whether modifiable cognitive factors moderate this association is unclear. This study examined whether Dysfunctional Beliefs and Attitudes about Sleep moderate the impact of sleep on next-day affect in young people.

METHODS

Four hundred and sixty-eight young people (205 adolescents, 54.1% female, M ± SDage=16.92 ± 0.87; 263 emerging adults, 71.9% female, M±SDage=21.29 ± 1.73) self-reported sleep and affect, and wore an actigraph for 7-28 days, providing >5000 daily observations. Linear mixed-effects models tested whether Dysfunctional Beliefs and Attitudes about Sleep moderated daily associations between self-reported and actigraphic sleep duration, sleep efficiency, and next-day affect on between- and within-person levels. Both valence (positive/negative) and arousal (high/low) dimensions of affect were examined. Covariates included age, sex, race/ethnicity, day of week, and previous-day affect.

RESULTS

Dysfunctional Beliefs and Attitudes about Sleep significantly moderated sleep and high arousal positive affect associations on between- but not within-person levels. Individuals with higher Dysfunctional Beliefs and Attitudes about Sleep (+1 SD) and lower average sleep duration (actigraphic: p = .020; self-reported: p = .047) and efficiency (actigraphic: p = .047) had significantly lower levels of high arousal positive affect. After adjusting for multiple comparisons, Dysfunctional Beliefs and Attitudes about Sleep did not moderate relationships between sleep duration and low arousal positive affect (p ≥ .340).

CONCLUSIONS

Young people with more unhelpful beliefs about sleep and shorter, or poorer, sleep may experience dampened levels of high arousal positive affect. DBAS may constitute a modifiable factor increasing affective vulnerability on a global but not day-to-day level. Intervention studies are needed to determine if changing Dysfunctional Beliefs and Attitudes about Sleep may reduce sleep-related affect disturbances in young people.

Effects of Savoring Meditation on Positive Emotions and Pain-Related Brain Function: A Mechanistic Randomized Controlled Trial in People With Rheumatoid Arthritis

Positive emotions are a promising target for intervention in chronic pain, but mixed findings across trials to date suggest that existing interventions may not be optimized to efficiently engage the target. The aim of the current mechanistic randomized controlled trial was to test the effects of a single skill positive emotion-enhancing intervention called Savoring Meditation on pain-related neural and behavioral targets in patients with rheumatoid arthritis (RA). Participants included 44 patients with a physician-confirmed diagnosis of RA (n=29 included in fMRI analyses), who were randomized to either Savoring Meditation or a Slow Breathing control. Both meditation interventions were brief (four 20-minute sessions). Self-report measures were collected pre- and post-intervention. An fMRI task was conducted at post-intervention, during which participants practiced the meditation technique on which they had been trained while exposed to non-painful and painful thermal stimuli. Relative to Slow Breathing, Savoring significantly reduced experimental pain intensity ratings relative to rest (p<.001), increased cerebral blood flow in the ventromedial prefrontal cortex (vmPFC) and increased connectivity between the vmPFC and caudate during noxious thermal stimulation (z=2.3 voxelwise, FDR cluster corrected p=0.05). Participants in the Savoring condition also reported significantly increased positive emotions (ps<.05) and reduced anhedonic symptoms (p<.01) from pre- to post-intervention. These findings suggest that that Savoring recruits reward-enhancing corticostriatal circuits in the face of pain, and future work should extend these findings to evaluate if these mechanisms of Savoring are associated with improved clinical pain outcomes in diverse patient populations.

Subjective Sleep Disturbances in Sexual Assault Survivors: Associations With Trauma and Posttraumatic Stress Disorder Symptom Severity

Prior work implicates sleep disturbance in the development and maintenance of posttraumatic stress disorder (PTSD). However, the majority of this literature has focused on combat veteran men, and limited work has examined links between sleep disturbance and PTSD symptoms in sexual assault survivors. This is a notable gap in the literature, as sexual trauma is disproportionately likely to result in PTSD and is more common in women. We sought to examine the relations between subjective sleep disturbance, sexual assault severity, and PTSD symptoms in a sample of sexual assault survivors with PTSD (PTSD+), without PTSD (PTSD-), and healthy controls. The sample (N = 60) completed the Insomnia Severity Index and prospectively monitored their sleep for 1 week using the Consensus Sleep Diary. The sexual assault survivors also completed the Sexual Experiences Survey and PTSD Checklist-5. Results of group comparisons found that the PTSD+ group reported significantly higher insomnia symptoms, longer sleep onset latency, more nocturnal awakenings, and lower sleep quality compared to the healthy control group and higher insomnia symptoms compared to the PTSD- group. Results of regression analyses in the sexual assault survivors found that insomnia symptoms and number of nocturnal awakenings were significantly associated with higher PTSD symptoms, and sexual assault severity was significantly associated with higher insomnia symptoms, longer sleep onset latency, and lower sleep quality. These findings highlight specific features of sleep disturbance that are linked to trauma and PTSD symptom severity among sexual assault survivors.

Sleep staging based on single-channel EEG and EOG with Tiny U-Net

Nowadays, many sleep staging algorithms have not been widely used in practical situations due to the lack of persuasiveness of generalization outside the given datasets. Thus, to improve generalization, we select seven highly heterogeneous datasets covering 9970 records with over 20k hours among 7226 subjects spanning 950 days for training, validation, and evaluation. In this paper, we propose an automatic sleep staging architecture called TinyUStaging using single-lead EEG and EOG. The TinyUStaging is a lightweight U-Net with multiple attention modules to perform adaptive recalibration of the features, including Channel and Spatial Joint Attention (CSJA) block and Squeeze and Excitation (SE) block. Noteworthily, to address the class imbalance problem, we design sampling strategies with probability compensation and propose a class-aware Sparse Weighted Dice and Focal (SWDF) loss function to improve the recognition rate for minority classes (N1) and hard-to-classify samples (N3) especially for OSA patients. Additionally, two hold-out sets containing healthy and sleep-disordered subjects are considered to verify the generalization. Facing the background of large-scale imbalanced heterogeneous data, we perform subject-wise 5-fold cross-validation on each dataset, and the results demonstrate that our model outperforms many methods, especially in N1, achieving an average overall accuracy, macro F1-score (MF1), and kappa of 84.62%, 79.6%, and 0.764 on heterogeneous datasets under optimal partitioning, providing a solid foundation for out-of-hospital sleep monitoring. Moreover, the overall standard deviation of MF1 under different folds remains within 0.175, indicating that the model is relatively stable.

A randomized, placebo-controlled, double-blinded mechanistic clinical trial using endotoxin to evaluate the relationship between insomnia, inflammation, and affective disturbance on pain in older adults: A protocol for the sleep and Healthy Aging Research for pain (SHARE-P) study

Chronic pain is prevalent in older adults. Treatment, especially with opioids, is often ineffective and poses considerable negative consequences in this population. To improve treatment, it is important to understand why older adults are at a heightened risk for developing chronic pain. Insomnia is a major modifiable risk factor for chronic pain that is ubiquitous among older adults. Insomnia can also lead to heightened systemic inflammation and affective disturbance, both of which may further exacerbate pain conditions in older adults. Endotoxin exposure can be used as an experimental model of systemic inflammation and affective disturbance. The current study aims to understand how insomnia status and endotoxin-induced changes in inflammation and affect (increased negative affect and decreased positive affect) may interact to impact pain facilitatory and inhibitory processes in older adults. Longitudinal data will also assess how pain processing, affective, and inflammatory responses to endotoxin may predict the development of pain and/or depressive symptoms. The current study is a randomized, double-blinded, placebo-controlled, mechanistic clinical trial in men and women, with and without insomnia, aged 50 years and older. Participants were randomized to either 0.8ng/kg endotoxin injection or saline placebo injection. Daily diaries were used to collect variables related to sleep, mood, and pain at two-week intervals during baseline and 3-, 6-, 9-, and 12-months post-injection. Primary outcomes during the experimental phase include conditioned pain modulation, temporal summation, and affective pain modulation ∼5.5 hours after injection. Primary outcomes for longitudinal assessments are self-reported pain intensity and depressive symptoms. The current study uses endotoxin as an experimental model for pain. In doing so, it aims to extend the current literature by: (1) including older adults, (2) investigating insomnia as a potential risk factor for chronic pain, (3) evaluating the role of endotoxin-induced affective disturbances on pain sensitivity, and (4) assessing sex differences in endotoxin-induced hyperalgesia.

Clinicaltrialsgov

NCT03256760.

Trial sponsor

NIH R01AG057750-01.

Investigation of pain sensitivity following 3 nights of disrupted sleep in healthy individuals

BACKGROUND

Poor quality sleep is a common complaint among people with chronic pain. The co-occurrence of poor sleep quality and chronic pain often comes with increased pain intensity, more disability and a higher cost of healthcare. Poor sleep has been suggested to affect measures of peripheral and central pain mechanisms. To date, sleep provocations are the only models proven to affect measures of central pain mechanisms in healthy subjects. However, there are limited studies investigating the effect of several nights of sleep disruption on measures of central pain mechanisms.

METHODS

The current study implemented three nights of sleep disruption with three planned awakenings per night in 30 healthy subjects sleeping at home. Pain testing was conducted at the same time of day at baseline and follow-up for each subject. Pressure pain thresholds were assessed bilaterally on the infraspinatus and gastrocnemius muscles. Using handheld pressure algometry, suprathreshold pressure pain sensitivity and area were also investigated on the dominant infraspinatus muscle. Cuff-pressure pain detection and tolerance thresholds, temporal summation of pain and conditioned pain modulation were investigated using cuff-pressure algometry.

RESULTS

Temporal summation of pain was significantly facilitated (p = 0.022), suprathreshold pain areas (p = 0.005) and intensities (p < 0.05) were significantly increased, and all pressure pain thresholds were decreased (p < 0.005) after sleep disruption compared to baseline.

CONCLUSIONS

The current study found that three consecutive nights of sleep disruption at home induced pressure hyperalgesia and increased measures of pain facilitation in healthy subjects, which is consistent with previous findings.

SIGNIFICANCE

Poor quality of sleep is often experienced by patients with chronic pain, with the most common complaint being nightly awakenings. This exploratory study is the first to investigate changes in measures of central and peripheral pain sensitivity in healthy subjects after sleep disruptions for three consecutive nights without any restrictions on total sleep time. The findings suggest that disruptions to sleep continuity in healthy individuals can induce increased sensitivity to measures of central and peripheral pain sensitization.

A nationwide study on pain manifestations and sleep problems in community-dwelling older adults: findings from ELSI-Brazil

PURPOSE

Sleep problems are common and affect approximately 36-70% of older adults worldwide and can be associated with negative outcomes such as pain. There is believed to be a bidirectional relationship between sleep problems and pain, modulated by inflammation and stress. The objective was to investigate the association between self-reported sleep problems and pain manifestations.

METHODS

A cross-sectional study using data from the second wave of the Brazilian Longitudinal Study of Aging (2019-2021) was conducted. The exposure variables were self-reported sleep problems: poor sleep quality, insomnia (initial, intermediate, and final), and daytime sleepiness. The outcomes were self-reported pain manifestations: frequent pain, moderate/intense/strong pain, and pain-related disability. Logistic regressions were performed to verify the association between exposures and outcomes.

RESULTS

A total of 6875 community-dwelling older adults participated in this study (71.1 ± 8.3 years; 54.4% female). Older adults with self-reported poor sleep quality, initial, intermediate and final insomnia, and daytime sleepiness had, respectively, 1.99 (95% CI 1.57-2.53), 1.47 (95% CI 1.11-1.97), 1.65 (95% CI 1.27-2.14), 1.69 (95% CI 1.29-2.22), and 1.76 (95% CI 1.35-2.29) greater odds of reporting frequent pain. The odds of moderate/intense/strong pain were higher in older adults that reported poor sleep quality (OR: 2.21; 95% CI 1.08-4.51). Older adults with self-reported poor sleep quality, initial, intermediate and final insomnia, and daytime sleepiness had, respectively, 1.84 (95% CI 1.11-3.02), 1.73 (95% CI 1.14-2.62), 1.80 (95% CI 1.19-2.73), 1.58 (95% CI 1.07-2.34), and 1.63 (95% CI 1.11-2.39) greater odds of reporting pain-related disability.

CONCLUSION

Self-reported sleep problems are associated with pain manifestations in older adults. The results may help in the proposition of programs and public health policies.

The effect of sleep continuity disruption on multimodal emotion processing and regulation: a laboratory-based, randomised, controlled experiment in good sleepers

Previous research shows that experimental sleep deprivation alters emotion processing, suggesting a potential mechanism linking sleep disruption to mental ill-health. Extending previous work, we experimentally disrupted sleep continuity in good sleepers and assessed next-day emotion processing and regulation using tasks with established sensitivity to depression. In a laboratory-based study, 51 good sleepers (37 female; mean [SD] age 24 [3.63] years), were randomised to 1 night of uninterrupted sleep (n = 24) or sleep continuity disruption (n = 27). We assessed emotion perception, attention, and memory the following day. Participants also completed an emotion regulation task and measures of self-reported affect, anxiety, sleepiness, overnight declarative memory consolidation, and psychomotor vigilance. Confirming the effects of the manipulation, sleep continuity disruption led to a marked decrease in polysomnography-defined total sleep time (229.98 versus 434.57 min), increased wake-time after sleep onset (260.66 versus 23.84 min), and increased sleepiness (d = 0.81). Sleep continuity disruption led to increased anxiety (d = 0.68), decreased positive affect (d = -0.62), reduced overnight declarative memory consolidation (d = -1.08), and reduced psychomotor vigilance (longer reaction times [d = 0.64] and more lapses [d = 0.74]), relative to control. However, contrary to our hypotheses, experimental sleep disruption had no effect on perception of, or bias for, emotional facial expressions, emotional memory for words, or emotion regulation following worry induction. In conclusion, 1 night of sleep continuity disruption had no appreciable effect on objective measures of emotion processing or emotion regulation in response to worry induction, despite clear effects on memory consolidation, vigilance, and self-reported affect and anxiety.

Two-year changes in sleep duration are associated with changes in psychological distress in adolescent girls and boys: the fit futures study

Objective

Studies indicate an inverse association between sleep duration and psychological distress. We aimed to explore associations between changes in sleep duration and changes in psychological distress in girls and boys.

Methods

The Fit Futures Study is a broad adolescent study providing data from 373 girls and 294 boys aged 15–18 years collected in 2010/2011 (FF1) and 2012/2013 (FF2). Psychological distress was measured by the Hopkins Symptom Checklist (HSCL-10) and sleep duration was self-reported. Change score variables were calculated as the change between baseline and follow-up for sleep duration and HSCL-10, respectively. Associations between changes in sleep duration and changes in HSCL-10 were explored by linear regressions, in gender-stratified analyses.

Results

At FF1, girls and boys slept on average 6.93 (SD = 1.08) and 7.05 (SD = 1.20) hours per night respectively, and correspondingly, 6.83 (SD = 1.19) and 6.85 (SD = 1.21) at FF2. At FF1, 22.8% of the girls and 25.8% of the boys slept ≤ 6 h per night, and correspondingly 28.0% and 28.2% at FF2. In girls and boys, one unit increase (30 min) in sleep duration was associated with a decrease in HSCL-10 score of B [95% CI] = −0.090 [−0.131, −0.048], p < 0.001, and −0.054 [−0.091, −0.017], p < 0.001, respectively. The associations remained significant after adjusting for confounders.

Conclusion

Our findings show that increased sleep duration was associated with decreased psychological distress during adolescence. Future studies should examine the causality between sleep duration and psychological distress.

Effect of sleep loss on pain-New conceptual and mechanistic avenues

Introduction

Sleep disturbances increase pain sensitivity in clinical and preclinical settings, but the precise mechanisms are unknown. This represents a major public health issue because of the growing sleep deficiency epidemic fueled by modern lifestyle. To understand the neural pathways at the intersection between sleep and pain processes, it is critical to determine the precise nature of the sleep disruptions that increase pain and the specific component of the pain response that is targeted.

Methods

We performed a review of the literature about sleep disturbances and pain sensitivity in humans and rodents by taking into consideration the targeted sleep stage (REMS, non-NREMS, or both), the amount of sleep lost, and the different types of sleep disruptions (partial or total sleep loss, duration, sleep fragmentation or interruptions), and how these differences might affect distinct components of the pain response.

Results

We find that the effects of sleep disturbances on pain are highly conserved among species. The major driver for pain hypersensitivity appears to be the total amount of sleep lost, while REMS loss by itself does not seem to have a direct effect on pain sensitivity. Sleep loss caused by extended wakefulness preferentially increases pain perception, whereas interrupted and limited sleep strongly dysregulates descending controls such as DNIC, especially in women.

Discussion

We discuss the possible mechanisms involved, including an increase in inflammatory processes, a loss of nociceptive inhibitory pathways, and a defect in the cognitive processing of noxious input.

An experimental test of the effects of acute sleep deprivation on affect and avoidance

BACKGROUND AND OBJECTIVES

Avoidance and sleep have been identified as mechanisms involved in the development and maintenance of many mental health disorders. However, there has been little research into the relation between sleep and avoidance.

METHODS

To address this, a randomized controlled experiment using behavioral and self-report measures of affect and avoidance was conducted. Compared to a control group, we hypothesized that sleep-deprived individuals would demonstrate increased negative, and decreased positive, affectivity, more avoidance behavior toward a negatively valenced stimulus, as well as increased self-reported avoidance. Fifty-two healthy individuals ages 18-30 years old were randomly assigned to a full night of sleep deprivation or normal sleep. They completed a baseline and post-manipulation behavioral avoidance task (BAT) using a disgusting stimulus and self-reports of avoidance and state affect.

RESULTS

Repeated measures ANOVAs demonstrated negative affectivity and self-reported avoidance increased, and positive affectivity decreased, from pre-to post-manipulation in the sleep loss condition as expected. However, there were no effects of sleep deprivation on avoidance behaviors.

LIMITATIONS

This study emphasized internal validity over generalizability. Additionally, the at-home sleep deprivation limited researcher control over the overnight activities of participants.

CONCLUSIONS

Results replicate prior work on the affective consequences of sleep deprivation and highlight a discrepancy between the effect of sleep deprivation on behavioral avoidance toward a specific stimulus compared to self-reported cognitive and social avoidance behaviors.

Preferential consolidation of emotional reactivity during sleep: A systematic review and meta-analysis

Many studies have investigated whether sleep affects cognitively unmodulated reactivity to emotional stimuli. These studies operationalize emotion regulation by using subjective and/or objective measures to compare pre- and post-sleep reactivity to the same emotional stimuli. Findings have been inconsistent: some show that sleep attenuates emotional reactivity, whereas others report enhanced or maintained reactivity. Across-study methodological differences may account for discrepant findings. To resolve the questions of whether sleep leads to the attenuation, enhancement, or maintenance of emotional reactivity, and under which experimental conditions particular effects are observed, we undertook a synthesized narrative and meta-analytic approach. We searched PubMed, PsycINFO, PsycARTICLES, Web of Science, and Cochrane Library databases for relevant articles, using search terms determined a priori and search limits of language = English, participants = human, and dates = January 2006–June 2021. Our final sample included 24 studies that investigated changes in emotional reactivity in response to negatively and/or positively valenced material compared to neutral material over a period of sleep compared to a matched period of waking. Primary analyses used random effects modeling to investigate whether sleep preferentially modulates reactivity in response to emotional stimuli; secondary analyses examined potential moderators of the effect. Results showed that sleep (or equivalent periods of wakefulness) did not significantly affect psychophysiological measures of reactivity to negative or neutral stimuli. However, self-reported arousal ratings of negative stimuli were significantly increased post-sleep but not post-waking. Sub-group analyses indicated that (a) sleep-deprived participants, compared to those who slept or who experienced daytime waking, reacted more strongly and negatively in response to positive stimuli; (b) nap-exposed participants, compared to those who remained awake or who slept a full night, rated negative pictures less negatively; and (c) participants who did not obtain substantial REM sleep, compared to those who did and those exposed to waking conditions, had attenuated reactivity to neutral stimuli. We conclude that sleep may affect emotional reactivity, but that studies need more consistency in methodology, commitment to collecting both psychophysiological and self-report measures, and should report REM sleep parameters. Using these methodological principles would promote a better understanding of under which conditions particular effects are observed.

Sleep and affect: A conceptual review

Everyday experience suggests that sleep and affect are closely linked, with daytime affect influencing how we sleep, and sleep influencing subsequent affect. Yet empirical evidence for this bidirectional relationship between sleep and affect in non-clinical adult samples remains mixed, which may be due to heterogeneity in both construct definitions and measurement. This conceptual review proposes a granular framework that deconstructs sleep and affect findings according to three subordinate dimensions, namely domains (which are distinct for sleep and affect), methods (i.e., self-report vs. behavioral/physiological measures), and timescale (i.e., shorter vs. longer). We illustrate the value of our granular framework through a systematic review of empirical studies published in PubMed (N = 80 articles). We found that in some cases, particularly for sleep disturbances and sleep duration, our framework identified robust evidence for associations with affect that are separable by domain, method, and timescale. However, in most other cases, evidence was either inconclusive or too sparse, resulting in no clear patterns. Our review did not find support for granular bidirectionality between sleep and affect. We suggest a roadmap for future studies based on gaps identified by our review and discuss advantages and disadvantages of our granular dimensional framework.

Baseline Sleep Disturbances Modify Outcome Trajectories in Adolescents With Chronic Pain Receiving Internet-Delivered Psychological Treatment

Over 50% of adolescents with chronic pain report comorbid sleep disturbances (eg, difficulties with falling asleep), which is associated with increased pain-related disability and poorer quality of life. However, limited longitudinal data are available to understand how sleep disturbance may impact response to psychological treatment. Our primary hypothesis was that baseline sleep disturbances would significantly modify how adolescents responded to an internet-delivered psychological intervention for chronic pain in terms of outcome trajectories. The sample included 85 adolescents, 12 to 17 years, with chronic pain recruited from a multidisciplinary pain clinic and headache clinic who received access to an internet-delivered psychological intervention for chronic pain. Baseline sleep assessment included actigraphy monitoring for 7 days and survey measures. Outcomes were assessed at baseline, 8 weeks, and 3 months including core pain-related outcomes, executive functioning, fatigue, positive and negative affect. Results demonstrated that greater baseline insomnia and poorer sleep quality was associated with worse outcome trajectories for pain-related disability, depression, anxiety, fatigue, negative affect, and executive functioning. Findings extend the limited studies that examine how sleep disturbance may modify effectiveness of psychological treatments for adolescent chronic pain and emphasize the importance of treating comorbid sleep disturbance. This trial was registered at clinicaltrials.gov (NCT04043962). PERSPECTIVE: Our study suggests that sleep deficiency, in particular insomnia and poor sleep quality, may modify the effectiveness of psychological treatments for chronic pain, highlighting the urgent need to screen youth for sleep problems prior to initiating treatment, and to consider implementation of sleep-specific treatments such as cognitive-behavioral therapy for insomnia.

Quarreling After a Sleepless Night: Preliminary Evidence of the Impact of Sleep Deprivation on Interpersonal Conflict

Although poor sleep has been found to correlate with deteriorations in romantic relationships, its causal impact on interpersonal conflict has not previously been studied. Therefore, 30 couples were randomly assigned to either a single night of total sleep deprivation or a night of normal sleep to test the effects of sleep deprivation on couples’ conflict. After the experimental night, all participants discussed a topic of recurrent conflict for 15 min. We collected pre- and post-conflict measures of cortisol, self-reports of feelings, and satisfaction with the conflictual discussion. Multilevel analyses revealed higher cortisol levels during conflict and less positive affect prior to and after the conflict for sleep-deprived couples compared to couples in the control condition. These findings provide initial evidence for a causal negative impact of sleep deprivation on couples’ conflicts.

Pain Expectancy and Positive Affect Mediate the day-to-day Association Between Objectively Measured Sleep and Pain Severity Among Women With Temporomandibular Disorder

The majority of individuals with temporomandibular disorders (TMD) experience sleep disturbance, which can maintain and exacerbate chronic pain. However, the factors underlying the sleep-pain link have not been fully elucidated, especially beyond the laboratory. Sleep deprivation can induce threat interpretation bias, as well as impairment in positive affective functioning. Using both actigraphy and daily diaries, we examined whether morning pain expectancy and positive affect mediate the association between previous night's sleep disturbance and next-day overall pain severity. Total sleep time (TST) was selected as the primary measure of sleep. The sample included 144 women (mean age = 36 [SD = 11.1]) with TMD who displayed at least subclinical insomnia. Sleep was assessed for 14 days using actigraphy which was validated by concurrent sleep diaries. Daily diary assessments of pain-related experiences and affective states were conducted twice per day (ie, once upon participants' waking and the other prior to going to sleep) for the same 14-day period. Multilevel structural equation modeling revealed that both morning pain expectancy (95% CI: -.0004, -.00003) and positive affect (95% CI: -.0005, -.000001) mediated the association between previous night's TST and next-day's overall pain severity, such that shorter previous night TST was associated with higher next-morning pain expectancy and lower positive affect, which in turn were associated with a greater level of next-day's overall pain severity while controlling for morning pain severity. Reducing exaggerated daily pain expectancy and up-regulating positive affect may be important intervention targets for disengaging the sleep-pain link among individuals with co-occurring TMD and sleep disturbance. PERSPECTIVE: The daily link between previous night sleep duration and next day pain severity is mediated by morning pain expectancy and positive affect among women with temporomandibular disorder and sleep disturbance. Reducing pain expectancy and increasing positive affect may serve an important role in improving self-management of chronic pain.

Interactions between Sleep and Emotions in Humans and Animal Models

Recently, increased interest and efforts were observed in describing the possible interaction between sleep and emotions. Human and animal model studies addressed the implication of both sleep patterns and emotional processing in neurophysiology and neuropathology in suggesting a bidirectional interaction intimately modulated by complex mechanisms and factors. In this context, we aimed to discuss recent evidence and possible mechanisms implicated in this interaction, as provided by both human and animal models in studies. In addition, considering the affective component of brain physiological patterns, we aimed to find reasonable evidence in describing the two-way association between comorbid sleep impairments and psychiatric disorders. The main scientific literature databases (PubMed/Medline, Web of Science) were screened with keyword combinations for relevant content taking into consideration only English written papers and the inclusion and exclusion criteria, according to PRISMA guidelines. We found that a strong modulatory interaction between sleep processes and emotional states resides on the activity of several key brain structures, such as the amygdala, prefrontal cortex, hippocampus, and brainstem nuclei. In addition, evidence suggested that physiologically and behaviorally related mechanisms of sleep are intimately interacting with emotional perception and processing which could advise the key role of sleep in the unconscious character of emotional processes. However, further studies are needed to explain and correlate the functional analysis with causative and protective factors of sleep impairments and negative emotional modulation on neurophysiologic processing, mental health, and clinical contexts.

Longitudinal, bidirectional relationships of insomnia symptoms and musculoskeletal pain across adolescence: the mediating role of mood

ABSTRACT

Previous studies have established a bidirectional relationship between sleep and pain, and mood has been proposed as a mediator of this relationship. There are only a limited number of longitudinal studies examining the mediational role of mood, and the directionality of effects between sleep, pain, and mood is uncertain. In addition, despite the high prevalence of pain and sleep problems during adolescence, these relationships have rarely been examined in a longitudinal sample of adolescents. Here, longitudinal survey data with 5 yearly measurements were used to examine the bidirectional relationship between insomnia symptoms and pain across adolescence (Mbaseline age = 13.65 years, Nbaseline = 2767). We also explored if depressed mood, positive affect, and anxious mood are mediators in both directions of the sleep-pain relationship. Using latent variables for insomnia, pain, and mood at multiple time points, the data were analyzed with cross-lagged panel models for longitudinal data with structural equation modeling. Current results confirmed a bidirectional relationship between insomnia symptoms and pain, where the effect of insomnia symptoms on pain was stronger than vice versa. Depressed mood and anxious mood mediated the effect of insomnia symptoms on pain, but not the reverse effect of pain on insomnia symptoms. Positive affect did not serve as a mediator in either direction. These findings add novel insights into the temporal directionality of sleep, pain, and mood during adolescence, suggesting a temporal path from sleep to pain, through mood, rather than a reciprocal relationship between the constructs.

Impact of total sleep deprivation and related mood changes on approach-avoidance decisions to threat-related facial displays

STUDY OBJECTIVES

Total sleep deprivation is known to have significant detrimental effects on cognitive and socio-emotional functioning. Nonetheless, the mechanisms by which total sleep loss disturbs decision-making in social contexts are poorly understood. Here, we investigated the impact of total sleep deprivation on approach/avoidance decisions when faced with threatening individuals, as well as the potential moderating role of sleep-related mood changes.

METHODS

Participants (n = 34) made spontaneous approach/avoidance decisions in the presence of task-irrelevant angry or fearful individuals, while rested or totally sleep deprived (27 h of continuous wakefulness). Sleep-related changes in mood and sustained attention were assessed using the Positive and Negative Affective Scale and the psychomotor vigilance task, respectively.

RESULTS

Rested participants avoided both fearful and angry individuals, with stronger avoidance for angry individuals, in line with previous results. On the contrary, totally sleep deprived participants favored neither approach nor avoidance of fearful individuals, while they still comparably avoided angry individuals. Drift-diffusion models showed that this effect was accounted for by the fact that total sleep deprivation reduced value-based evidence accumulation toward avoidance during decision making. Finally, the reduction of positive mood after total sleep deprivation positively correlated with the reduction of fearful display avoidance. Importantly, this correlation was not mediated by a sleep-related reduction in sustained attention.

CONCLUSIONS

All together, these findings support the underestimated role of positive mood-state alterations caused by total sleep loss on approach/avoidance decisions when facing ambiguous socio-emotional displays, such as fear.

Associations Between Intraindividual Variability in Sleep and Daily Positive Affect

Recent research highlights a variety of negative outcomes associated with intraindividual variability in positive affect (PA) and in sleep. Thus, this study examined the associations of variability in multiple dimensions of sleep (quality, duration, wake after sleep onset, bedtime, rise-time) with mean and variability in PA. For 7 days, morning and evening surveys were collected online from two separate samples: community-based adults (N = 911) and university students (N = 322). Regression analyses revealed that across both samples, people with more variable sleep quality exhibited greater fluctuations in PA throughout the week and, surprisingly, higher levels of PA on average. In the community sample only, individuals with more variable sleep duration had lower and more variable PA. Findings suggest that fluctuations in sleep quality and duration are linked with daily PA outcomes, which is important to consider as technological advances and modern demands make inadequate and irregular sleep increasingly common.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42761-021-00082-6.

I feel good? Anhedonia might not mean "without pleasure" for people treated for opioid use disorder

Anhedonia is usually defined as partial or total loss of the capacity for pleasure. People with anhedonia in the context of major depressive disorder may have an unexpected capacity for event-related mood brightening, observable when mood is assessed dynamically (with smartphone-based ecological momentary assessment [EMA]) rather than only statically via questionnaire. We used EMA to monitor mood and pleasant events for 4 weeks in 54 people being treated with opioid agonist medication for opioid-use disorder (OUD), which is also associated with anhedonia, said to manifest especially as loss of pleasure from nondrug reward. We compared OUD patients' EMA reports with those of 47 demographically similar controls. Background positive mood was lower in OUD patients than in controls, as we hypothesized (Cohen ds = .85 to 1.32, 95% CIs [.66, 1.55]), although, contrary to our hypothesis, background negative mood was also lower (ds = .82 to .85, 95% CIs [.73, .94]). As hypothesized, instances of nondrug pleasure were as frequent in OUD patients as in controls-and were not rated much less pleasurable (d = .18, 95% CI [-.03, .35]). Event-related mood brightening occurred in both abstinent and nonabstinent OUD patients (ds = .18 to .37, CIs [-.01, .57]) and controls (ds = .04 to .60, CIs [-.17, .79]), brightening before each event began earlier for controls than OUD patients, but faded similarly postevent across groups. Our findings add to the evidence that anhedonia does not rule out reactive mood brightening, which, for people with OUD being treated on opioid agonist medication, can be elicited by nondrug activities. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Trait positive affect buffers the association between experimental sleep disruption and inflammation

BACKGROUND

Sleep disturbances and insufficient sleep are highly prevalent. Both clinical sleep disorders and multiple forms of experimental sleep loss predict heightened inflammation. As such, it is necessary to investigate potential protective factors. Given that trait positive affect (PA) is associated with reduced inflammation, and buffers the proinflammatory effects of stress, it is possible that high trait positive affect might protect individuals from an inflammatory response to sleep disruption. The present study tested this hypothesis in an experimental sleep disruption paradigm with assessment of cellular inflammation.

METHODS

Data were drawn from good sleeping adults (n = 79) who participated in a randomized, within-subjects crossover experiment comparing the effects of two nights of sleep disruption versus two nights of uninterrupted sleep. Stimulated monocytic production of intracellular proinflammatory cytokines tumor necrosis factor (TNF) and interleukin-6 (IL-6) were assayed using flow cytometric methods and indexed as the percentage of monocytes expressing TNF, IL-6, or co-expressing both. Hypotheses were evaluated using linear mixed effects models.

RESULTS

Controlling for negative affect, body mass index, age, and sex, PA significantly moderated the associations between sleep condition and stimulated monocyte production of IL-6 (b = -1.03, t = -2.02, p = .048) and its co-expression with TNF (b = -0.93, t = -2.00, p = .049), such that inflammatory responses were blunted among those high in PA with increases principally among those low in PA. The effect on TNF was similar in terms of effect size, but marginally significant.

CONCLUSIONS

Activation of cellular inflammation in response to sleep disruption is buffered by PA independent of negative affect. Interventions that promote PA might protect persons from the inflammatory activation following sleep loss, with the potential to mitigate the adverse health consequences of sleep disturbance.

Eveningness Predicts Negative Affect Following Sleep Restriction

Although considerable research has shown that sleep loss results in decreased positive affect, findings regarding change in negative affect are inconsistent. Such inconsistency may be due in part to variability in individual difference factors, such as chronotype, which is associated with both sleep and affective outcomes. Chronotype represents the tendency to be a morning- or evening-type person and is underpinned by the timing of circadian processes linked to sleep and mental health. The present study examined the predictive effect of chronotype above and beyond that of depression on affective response to sleep restriction in a sample of healthy sleeping adults (n = 73). Participants completed measures of chronotype and depression at baseline and measures of positive and negative affect before and after one night of sleep restriction (4 hours between 4 a.m. and 8 a.m.). Results indicate a large, significant decrease in positive affect following sleep restriction, but no statistically significant change in negative affect. Subsequent analyses showed that chronotype predicted affective response to sleep restriction, such that eveningness predicted a medium, significant increase in negative affect following sleep restriction, controlling for depression-however, there was no association between chronotype and change in positive affect in response to sleep restriction. These findings highlight a differential effect of sleep loss on positive and negative affect and suggest that evening chronotype may confer a distinct vulnerability for increased negative affect following sleep loss.

Long-term changes in self-reported sleep quality and risk of chronic musculoskeletal pain: The HUNT Study

We examined the association between long-term (~10 years) changes in self-reported sleep quality and risk of any chronic musculoskeletal pain and chronic widespread pain. The study comprised data on 6,033 people who participated in three consecutive surveys in the Norwegian HUNT Study (1995-1997, 2006-2008 and 2017-2019) and who were without chronic musculoskeletal pain at the first two surveys. We used a modified Poisson regression model to calculate adjusted risk ratios for chronic pain at follow-up (2017-2019) associated with categories of poor and good sleep quality reported in 1995-1997 and 2006-2008. Compared with people who reported good sleep at both surveys (crude absolute risk: 32.4%), the risk ratios of any chronic pain were 1.20 (95% confidence interval: 1.02-1.41) for those who changed from poor to good sleep; 1.25 (95% confidence interval: 1.12-1.39) for those who changed from good to poor sleep; and 1.41 (95% confidence interval: 1.21-1.63) for those who reported long-term poor sleep. The corresponding risk ratios for chronic widespread pain were 1.35 (95% confidence interval: 0.82-2.23), 1.55 (95% confidence interval: 1.14-2.12) and 2.09 (95% confidence interval: 1.38-3.17), respectively. In conclusion, these findings indicate that people with long-term poor sleep quality have a markedly higher risk of chronic musculoskeletal pain and chronic widespread pain, compared with people who remain good sleep quality.

An Attention-Based Deep Learning Approach for Sleep Stage Classification With Single-Channel EEG

Automatic sleep stage mymargin classification is of great importance to measure sleep quality. In this paper, we propose a novel attention-based deep learning architecture called AttnSleep to classify sleep stages using single channel EEG signals. This architecture starts with the feature extraction module based on multi-resolution convolutional neural network (MRCNN) and adaptive feature recalibration (AFR). The MRCNN can extract low and high frequency features and the AFR is able to improve the quality of the extracted features by modeling the inter-dependencies between the features. The second module is the temporal context encoder (TCE) that leverages a multi-head attention mechanism to capture the temporal dependencies among the extracted features. Particularly, the multi-head attention deploys causal convolutions to model the temporal relations in the input features. We evaluate the performance of our proposed AttnSleep model using three public datasets. The results show that our AttnSleep outperforms state-of-the-art techniques in terms of different evaluation metrics. Our source codes, experimental data, and supplementary materials are available at https://github.com/emadeldeen24/AttnSleep.

Emotional Vulnerability to Short Sleep Predicts Increases in Chronic Health Conditions Across 8 Years

BACKGROUND

Sleep is a robust determinant of next-day emotions, but people vary in the extent that their emotions fluctuate on days following short sleep duration. These individual differences in day-to-day sleep and emotion dynamics may have long-term health implications.

PURPOSE

To evaluate emotional vulnerability to short sleep (within-person associations between sleep duration and next-day emotions) as a risk factor for future chronic conditions.

METHODS

Adults aged 33-84 (N = 1,426; 57% female) in the Midlife in the United States Study reported sleep duration and emotions by telephone for eight consecutive days. Chronic conditions were assessed via checklist at baseline and at a median follow-up of eight years (range: 5-10 years). Short sleep was examined in three ways: person-centered continuous variable, ≤6 hr, and <7 hr; long sleep was defined as ≥9 hr.

RESULTS

Multilevel structural equation models revealed that people with greater negative emotions following nights of sleep ≤6 hr (vs. their negative emotions after longer sleep) had increased chronic conditions at follow-up, compared to people who were less emotionally vulnerable to short sleep (Est. = 1.04, SE = .51, p < .028). Smaller declines in positive emotions following ≤6 hr of sleep were marginally predictive of lower risk for chronic conditions (Est. = -.77, SE = .44, p = .054). Emotional vulnerability to <7, ≥9, and continuous sleep hours were not associated with subsequent chronic conditions.

CONCLUSIONS

Emotional vulnerability to short sleep is a unique risk factor for the development of chronic conditions, independent of mean-level sleep duration and emotions.

Impact of exercise on older adults' mood is moderated by sleep and mediated by altered brain connectivity

Older adults comprise the fastest growing global demographic and are at increased risk of poor mental health outcomes. Although aerobic exercise and sleep are critical to the preservation of emotional well-being, few studies have examined their combined mood-enhancing effects, or the potential neural mechanisms underlying these effects. Here, we used a randomized crossover design to test the impact of acute exercise on mood and the intrinsic functional connectivity (iFC) of the cingulo-opercular network in physically healthy older adults. Wrist actigraphy provided objective indices of sleep. Results revealed that 30 min of moderate-intensity aerobic exercise acutely enhanced positive affect (PA) and reduced iFC between the cingulo-opercular network and the hippocampus. Both effects were magnified among older adults with greater sleep disturbance. Exercise-induced changes in hippocampal iFC mediated relations between sleep disturbance and exercise-induced increases in PA. These findings provide evidence that aerobic exercise enhances mood, that it does so by altering connectivity between the anterior insula-a key hub in the cingulo-opercular network-and the hippocampus and that lower sleep quality is a stronger predictor of these effects among older adults. These observations underscore the benefits of moderate-intensity exercise-a safe and scalable behavioral intervention-and provide new clues about the neural circuitry underlying the interactive effects of sleep and exercise on mood.

Selective suppression of rapid eye movement sleep increases next-day negative affect and amygdala responses to social exclusion

Healthy sleep, positive general affect, and the ability to regulate emotional experiences are fundamental for well-being. In contrast, various mental disorders are associated with altered rapid eye movement (REM) sleep, negative affect, and diminished emotion regulation abilities. However, the neural processes mediating the relationship between these different phenomena are still not fully understood. In the present study of 42 healthy volunteers, we investigated the effects of selective REM sleep suppression (REMS) on general affect, as well as on feelings of social exclusion, cognitive reappraisal (CRA) of emotions, and their neural underpinnings. Using functional magnetic resonance imaging we show that, on the morning following sleep suppression, REMS increases general negative affect, enhances amygdala responses and alters its functional connectivity with anterior cingulate cortex during passively experienced experimental social exclusion. However, we did not find effects of REMS on subjective emotional ratings in response to social exclusion, their regulation using CRA, nor on functional amygdala connectivity while participants employed CRA. Our study supports the notion that REM sleep is important for affective processes, but emphasizes the need for future research to systematically investigate how REMS impacts different domains of affective experience and their neural correlates, in both healthy and (sub-)clinical populations.

Sleep restriction alters children's positive emotional responses, but effects are moderated by anxiety

BACKGROUND

An abundance of cross-sectional research links inadequate sleep with poor emotional health, but experimental studies in children are rare. Further, the impact of sleep loss is not uniform across individuals and pre-existing anxiety might potentiate the effects of poor sleep on children's emotional functioning.

METHODS

A sample of 53 children (7-11 years, M = 9.0; 56% female) completed multimodal, assessments in the laboratory when rested and after two nights of sleep restriction (7 and 6 hr in bed, respectively). Sleep was monitored with polysomnography and actigraphy. Subjective reports of affect and arousal, psychophysiological reactivity and regulation, and objective emotional expression were examined during two emotional processing tasks, including one where children were asked to suppress their emotional responses.

RESULTS

After sleep restriction, deleterious alterations were observed in children's affect, emotional arousal, facial expressions, and emotion regulation. These effects were primarily detected in response to positive emotional stimuli. The presence of anxiety symptoms moderated most alterations in emotional processing observed after sleep restriction.

CONCLUSIONS

Results suggest inadequate sleep preferentially impacts positive compared to negative emotion in prepubertal children and that pre-existing anxiety symptoms amplify these effects. Implications for children's everyday socioemotional lives and long-term affective risk are highlighted.

Sleep and Pain: A Systematic Review of Studies of Mediation

Supplemental Digital Content is available in the text.

Objectives:

A relationship between sleep and pain is well established. A better understanding of the mechanisms that link sleep and pain intensity is urgently needed to optimize pain management interventions. The objective of this systematic review was to identify, synthesize, and critically appraise studies that have investigated putative mediators on the path between sleep and pain intensity.

Methods:

A systematic search of 5 electronic bibliographic databases (EMBASE, MEDLINE, CINAHL, PsycINFO, and the Cochrane Central Register of Controlled Trials) was conducted. Eligible studies had to apply a formal test of mediation to variables on the path between a sleep variable and pain intensity or vice versa. All searches, data extraction and quality assessment were conducted by at least 2 independent reviewers.

Results:

The search yielded 2839 unique articles, 9 of which were eligible. Of 13 mediation analyses, 11 investigated pathways from a sleep variable to pain intensity. Putative mediators included affect/mood, depression and/or anxiety, attention to pain, pain helplessness, stress, fatigue, and physical activity. Two analyses investigated pathways from pain intensity to a sleep variable, examining the potentially mediating role of depressive symptoms and mood. Although evidence supported a mediating role for psychological and physiological aspects of emotional experiences and attentional processes, methodological limitations were common, including use of cross-sectional data and minimal adjustment for potential confounders.

Discussion:

A growing body of research is applying mediation analysis to elucidate mechanistic pathways between sleep and pain intensity. Currently sparse evidence would be illuminated by more intensively collected longitudinal data and improvements in analysis.

Sleep duration and affective reactivity to stressors and positive events in daily life

OBJECTIVE

Experimental evidence suggests that inadequate sleep disrupts next-day affective processing and evokes greater stress reactivity. However, less research has focused on whether sleep predicts next-day affective reactivity to naturally occurring stressors and positive events in daily life, as well as the reversed direction of association (i.e., affective reactivity to daily events as predictors of subsequent sleep). The purpose of this study was to evaluate the within-person, bidirectional associations between nightly sleep duration and day-to-day fluctuations in affect related to stressors and positive events.

METHOD

Adults ages 33-84 (N = 1,982, 57% female) in the U.S. National Study of Daily Experiences II reported sociodemographics and chronic conditions at baseline, then completed telephone interviews for 8 consecutive days about their sleep duration, daily stressors, positive events, and affect.

RESULTS

Prior-night sleep duration moderated the link between current-day events and positive affect, but not negative affect. Specifically, nights of shorter-than-usual sleep duration predicted more pronounced decreases in positive affect in response to daily stressors, as well as smaller increases in positive affect in response to daily positive events. Results for the reversed direction of association showed no evidence for affective reactivity to daily events as predictors of subsequent sleep duration. People with more chronic conditions were more reactive to positive events, particularly after nights of longer sleep.

CONCLUSION

Affective reactivity to daily stressors and positive events vary based upon sleep duration, such that sleep loss may amplify loss of positive affect on days with stressors, as well as reduce positive affective responsiveness to positive events. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Experimental sleep disruption and reward learning: moderating role of positive affect responses

STUDY OBJECTIVES

Sleep disturbances increase vulnerability for depression, but the mechanisms underlying this relationship are not well known. We investigated the effects of experimental sleep disruption on response bias (RB), a measure of reward learning previously linked to depression, and the moderating role of positive affect responses.

METHODS

Participants (N = 42) were healthy adults enrolled in a within-subject crossover sleep disruption experiment that incorporated one night of uninterrupted sleep (US) and one night of forced awakenings (FA) in random order. On the day following each experimental sleep night, participants completed a probabilistic reward task to assess RB, and the Positive and Negative Affect Schedule-X. Participants were subgrouped according to positive affect responses: Preserved Positive Affect (i.e. positive affect scores maintained or increased; n = 15) or Reduced Positive Affect (i.e. positive affect scores decreased; n = 27) following FA.

RESULTS

Contrary to our hypotheses, across participants, RB did not significantly differ between the US and FA sleep conditions (p = .67). However, the effect of sleep condition on RB was moderated by positive affect response (p = .01); those with preserved positive affect showed heightened RB following FA, whereas those with reduced positive affect showed diminished RB following FA. Changes in negative affect between US and FA did not moderate RB.

CONCLUSION

The inability to preserve positive affect through periods of sleep disruption may be a marker of diminished reward learning capability. Understanding how sleep disruption impacts positive affect responses and reward learning identifies a pathway by which sleep disturbances may confer risk for depression.

Insomnia and posttraumatic stress symptoms: Evidence of shared etiology

Posttraumatic stress disorder (PTSD) and insomnia are comorbid clinical conditions that are thought to result from genetic and environmental effects. Though studies have established the heritability of these disorders independently, no study to date has examined the genetic contributions to the relation between insomnia and PTSD symptoms (PTSS). The present study assessed this gap in the literature using a behavioral genetics approach to symptom dimensions. The sample consisted of 242 twin pairs who endorsed lifetime trauma exposure. Insomnia symptoms were assessed with the Women's Health Initiative Survey, and intrusion and avoidance PTSS were assessed with the Impact of Events Scale. Structural equation modeling was then employed to test the relative contributions of genetic, shared environmental, and nonshared environmental components to the relations between insomnia symptoms and intrusions and avoidance. Results indicated a significant association between insomnia symptoms and intrusions (r = 0.33, p < 0.01) and insomnia symptoms and avoidance (r = 0.20, p < 0.01), and 36-44% of phenotypic variance was accounted for by genetic contributions. These findings highlight a significant role for genetic factors in the mechanisms underlying the comorbidity between insomnia and PTSS. The implications for current etiological models of PTSD and insomnia are discussed.

Sleep in the anxiety-related disorders: A meta-analysis of subjective and objective research

Although sleep disturbance is implicated in psychopathology, its role in anxiety-related disorders remains unclear. The present meta-analysis characterizes sleep disturbance in anxiety-related disorders collectively and individually. Subjective measures of total sleep time and sleep continuity were included with objective measures. Results indicate a large effect for increased subjective sleep disturbance (g = 2.16), medium effects for decreased total sleep time (g = -.40) and sleep continuity (g = -.49), and a small effect for decreased sleep depth (g = -.20) in anxiety-related disorders compared to healthy controls. Each anxiety-related disorder exhibited a distinct sleep disturbance pattern, suggesting that sleep may facilitate identification of unique biopsychological underpinnings. Effects were not moderated by comorbid depression and were similar in magnitude to those found for depression. Sleep disturbances, particularly decreased sleep continuity, may be a key pathology in the anxiety-related disorders that could highlight novel etiological mechanisms and intervention targets.

Multimodal assessment of sleep in men and women during treatment for opioid use disorder

BACKGROUND

Sleep disturbance is common in patients with opioid use disorder (OUD) receiving medication for addiction treatment. Differences between patients on the two primary agonist medications-methadone and buprenorphine-are not well understood.

METHODS

In patients receiving either methadone or buprenorphine treatment for OUD, we examined sleep continuity and architecture using ambulatory monitoring to gather both an objective measure (daily sleep EEG; M = 5.76 days, SD = 1.46) and a subjective measure (daily sleep diary; M = 54.10 days, SD = 25.10) of sleep.

RESULTS

Patients treated with buprenorphine versus methadone did not differ on any measure of sleep continuity or architecture. Women had longer EEG-derived total sleep time than men (d = -0.68, 95 % CI -1.32 to -0.09), along with lower %N2 (d = 0.94, 95 % CI 0.34-1.64) and greater %N3 (d = -0.94, 95 % CI -1.61 to -0.32). Self-reported sleep differed from EEG-derived estimates: wake after sleep onset was greater by EEG than by diary (d = 2.58, 95 % CI 1.74-3.63), and total sleep time and sleep efficiency were lower by EEG than by diary (d for sleep time = 2.93, 95 % CI 2.06-4.14; d for efficiency = 1.69, 95 % CI 0.98-2.49).

CONCLUSIONS

Patients treated with buprenorphine or methadone did not substantively differ in ambulatory measures of sleep. With both medications, there was a discrepancy between objective and subjective sleep measures. Further confirmatory evidence would inform the development of sleep-related recommendations for OUD patients undergoing agonist treatment.