To sleep or not to sleep, that is the question: A systematic review and meta-analysis on the effect of post-trauma sleep on intrusive memories of analog trauma.

Distressing intrusive memories of a traumatic event are one of the hallmark symptoms of posttraumatic stress disorder. Thus, it is crucial to identify early interventions that prevent the occurrence of intrusive memories. Both, sleep and sleep deprivation have been discussed as such interventions, yet previous studies yielded contradicting effects. Our systematic review aims at evaluating existing evidence by means of traditional and individual participant data (IPD) meta-analyses to overcome power issues of sleep research. Until May 16th, 2022, six databases were searched for experimental analog studies examining the effect of post-trauma sleep versus wakefulness on intrusive memories. Nine studies were included in our traditional meta-analysis (8 in the IPD meta-analysis). Our analysis provided evidence for a small effect favoring sleep over wakefulness, log-ROM = 0.25, p < .001, suggesting that sleep is associated with a lower number of intrusions but unrelated to the occurrence of any versus no intrusions. We found no evidence for an effect of sleep on intrusion distress. Heterogeneity was low and certainty of evidence for our primary analysis was moderate. Our findings suggest that post-trauma sleep has the potential to be protective by reducing intrusion frequency. More research is needed to determine the impact following real-world trauma and the potential clinical significance.

The predictive power of insomnia symptoms on other aspects of mental health during the COVID-19 pandemic: a longitudinal study.

Symptoms of insomnia are an important risk factor for the development of mental disorders, especially during stressful life periods such as the coronavirus disease 2019 (COVID-19) pandemic. However, up to now, most studies have used cross-sectional data, and the prolonged impact of insomnia symptoms during the pandemic on later mental health remains unclear. Therefore, we investigated insomnia symptoms as a predictor of other aspects of mental health across 6 months, with altogether seven assessments (every 30 days, t0-t6), in a community sample (N = 166-267). Results showed no mean-level increase of insomnia symptoms and/or deterioration of mental health between baseline assessment (t0) and the 6- month follow-up (t6). As preregistered, higher insomnia symptoms (between persons) across all time points predicted reduced mental health at the 6-month follow-up. Interestingly, contrary to our hypothesis, higher insomnia symptoms at 1 month, within each person (i.e., compared to that person's symptoms at other time points), predicted improved rather than reduced aspects of mental health 1 month later. Hence, we replicated the predictive effect of averagely increased insomnia symptoms on impaired later mental health during the COVID-19 pandemic. However, we were surprised that increased insomnia symptoms at 1 month predicted aspects of improved mental health 1 month later. This unexpected effect might be specific for our study population and a consequence of our study design. Overall, increased insomnia symptoms may have served as a signal to engage in, and successfully implement, targeted countermeasures, which led to better short-term mental health in this healthy sample.

Symptom dynamics among nightmare sufferers: An intensive longitudinal study.

Nightmares are considerably prevalent in the general population and are known to be closely associated with a variety of mental disorders. However, not much is known about the immediate antecedents and consequences of nightmares. Therefore, we used intensive longitudinal assessments to investigate the night-to-night within-person associations between nightmares on the one hand and fear of sleep, somatic as well as cognitive pre-sleep arousal, and sleep quality on the other hand. Young women with regular nightmares (n = 16) maintained a sleep diary for around 30 days; upon awaking, the participants reported on nightmares and sleep quality during the past night as well as the pre-sleep levels of arousal and fear of sleep (which resulted in 461 observations). Participants also wore an actigraph, which provided objective sleep parameters. Multilevel modeling showed that higher levels of fear of sleep and lower subjective sleep quality were significantly associated with higher levels of nightmare distress. Furthermore, we found individual differences in the strength of these associations, which implies that factors proximate to nightmares may vary across individuals. Pre-sleep arousal, however, did not show expected within-person associations with nightmares or fear of sleep. These findings highlight the crucial role of fear of sleep in the etiology of nightmares and sleep disturbances, while pointing to the importance of pursuing individual, personalised models that explain heterogeneity in the process of triggering nightmares.

Temporal associations between trauma-related sleep disturbances and PTSD symptoms: An experience sampling study.

OBJECTIVE: There is robust evidence for the influence of sleep disturbances on the maintenance of PTSD symptoms. However, little is known about day-to-day variation in trauma-related sleep disturbances (namely insomnia symptoms and nightmares) and their associations with PTSD symptoms. Therefore, we explored the dynamic interplay of these symptoms in daily life using an experience sampling method (ESM). METHOD: For 15 consecutive days, participants with PTSD symptomatology as primary complaint (N = 48) reported momentary levels of insomnia symptoms and nightmares as well as PTSD symptoms via a mobile app. RESULTS: Multilevel model analyses revealed that insomnia and nightmares were significant predictors of PTSD symptomatology on the following day; furthermore, nightmares were predictive of each of the four PTSD symptom clusters, namely reexperiencing, avoidance, cognition and hyperarousal as well as symptoms of dissociation. However, PTSD symptoms did not predict insomnia or nightmares during the following night. Multilevel mediation analyses suggested that nightmares mediate the relationship between insomnia and next-day PTSD symptoms. CONCLUSIONS: These findings support accumulating evidence that trauma-related sleep disturbances play an important role in the maintenance of PTSD symptoms, by elevating symptoms daily. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

(When and how) does basic research in clinical psychology lead to more effective psychological treatment for mental disorders?

An important aim of basic research in Clinical Psychology is to improve clinical practice (e.g., by developing novel interventions or improving the efficacy of existing ones) based on an improved understanding of key mechanisms involved in psychopathology. In the first part of this article, we examine how frequently this translation has happened in the past by reviewing all 40 evidence-based psychological interventions recommended in current clinical guidelines for five important (groups of) mental disorders. Results show that only 23% of treatments showed a very strong link between basic research and the development of the intervention, and further 20% showed a strong link. These findings thus suggest that the route from basic research to clinical innovation may not be as strong historically as is commonly assumed. Important challenges for translational research in clinical psychology are reviewed, leading to the introduction of a new framework, and a discussion of possible solutions to overcome these challenges. Suggestions include increased attention to robust and replicable research findings, a stronger focus on experimental psychopathology research to establish causality of psychopathological mechanisms, a more systematic structural integration of basic and applied research in clinical psychology, a stronger emphasis on mechanisms of change and moderators of clinical interventions, increased attention to clinical subgroups, and emphasizing improvements to existing interventions over the development of novel interventions.

Efficacy of approach bias modification as an add-on to smoking cessation treatment: study protocol for a randomized-controlled double-blind trial.

BACKGROUND: Although effective treatments for smoking cessation are available, long-term abstinence is the exception rather than the norm. Accordingly, there is a need for novel interventions that potentially improve clinical outcome. Although implicit information processing biases, for example approach biases for smoking-related stimuli, are ascribed a dominant role in the maintenance of tobacco dependence, these biases are hardly targeted in current treatment. Past research has shown that so-called Approach Bias Modification (AppBM) trainings, aiming to modify this bias, lead to improved long-term abstinence in abstinent alcoholic inpatients when delivered as an add-on to treatment-as-usual. Findings on the efficacy of AppBM in smoking have been inconsistent. The present large-scale clinical trial pursues two goals. First, it aims to investigate the efficacy of AppBM as an add-on to treatment-as-usual in a representative sample of adult smokers. Second, possible mechanisms of change are investigated. METHODS: The study is a randomized-controlled, double-blind, parallel-group superiority trial. We aim at a final sample of at least 336 adult smokers. Participants are allocated with a 1:1:1 allocation ratio to one of the following conditions: (1) treatment-as-usual + AppBM, (2) treatment-as-usual + Sham, (3) treatment-as-usual only. During the add-on training, participants are presented smoking-related and positive pictures and are instructed to respond by either pushing or pulling a joystick, depending on the tilt of the pictures (5○ to the left/right). During AppBM, all smoking-related pictures are tilted in the direction that is associated with pushing, thereby aiming to train an avoidance bias for smoking. All positive pictures are tilted in the direction associated with pulling. During Sham, the contingency is 50/50. Participants are assessed before and after the intervention and at a 6-month follow-up. The primary outcome is prolonged abstinence, and secondary outcomes include smoking-related variables and psychological distress. Additionally, the motivational significance of smoking-related stimuli (i.e., approach bias, valence) is assessed with different experimental tasks (Approach-Avoidance Task; Single Target Implicit Association Test) and psychophysiological measures. DISCUSSION: This is the first large-scale clinical trial investigating the efficacy of AppBM as an add-on in smokers including a TAU only condition. Additionally, it is the first study to systematically investigate potential mechanisms mediating the effects of treatment on clinical outcome. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00019221 , 11/11/2019.

Differential Effects of REM Sleep on Emotional Processing: Initial Evidence for Increased Short-term Emotional Responses and Reduced Long-term Intrusive Memories.

Background: Rapid eye movement (REM) sleep has been postulated to facilitate emotional processing of negative stimuli. However, empirical evidence is mixed and the conditions under which higher amounts of REM sleep lead to decreased or increased emotional responses are unclear. We proposed that the time course between REM sleep and measurement of emotional responses is a crucial factor and hypothesized that more REM sleep will enhance emotional responses shortly after sleep, but will lead to decreased emotional responses in the long-term. Participants and Methods: Seventy-six healthy young women watched negative and neutral pictures before a polysomnographically-recorded nap including three different groups (1: no REM sleep, 2: REM sleep awakening, 3: REM sleep). Short-term emotional responses were measured using aversiveness ratings of negative pictures; aversiveness ratings of intrusive picture memories on the three subsequent evenings were used to measure long-term emotional responses. Results: For short-term emotional responses, no significant interaction indicating group differences was found. However, we found correlations between longer REM sleep duration and higher aversiveness ratings of negative pictures. In contrast, lower aversiveness of intrusive picture memories after two days was found in participants with a full REM sleep period compared to individuals without REM sleep. Correlational analyses also supported this pattern of results. Conclusions: Results suggest that REM sleep may increase reactivity to emotional stimuli in the short-term and this effect of REM sleep appears to facilitate emotional processing during subsequent nights leading to reduced intrusive picture memories in the long-term.

Fear of sleep and trauma-induced insomnia: A review and conceptual model.

Trauma-induced insomnia is a symptom of posttraumatic stress disorder (PTSD), and is reported to be particularly distressing and often persists even after remission of the core symptoms of PTSD. Recently, it has been suggested that fear of sleep plays an important role in the development and maintenance of trauma-induced insomnia. The aim of this review is to propose a conceptual model of fear of sleep as a maintaining factor of trauma-induced insomnia. After a brief overview of the role of sleep in PTSD, the concept of fear of sleep is introduced. Theoretical considerations and empirical findings on the role of fear of sleep for trauma-induced insomnia in the context of PTSD are summarized and integrated. Specifically, links between PTSD symptoms and fear of sleep are presented, as well as possible consequences of fear of sleep leading to trauma-induced insomnia. Finally, we highlight methodological issues, identify areas for future research, and discuss potential clinical implications.

Misperception of sleep is associated with intrinsic motivation toward thinking about sleep.

BACKGROUND AND OBJECTIVES: Misperception of sleep, the underestimation of total sleep time and overestimation of sleep onset latency (SOL) relative to objective measures, is often found in people with sleep disturbances. Theories of insomnia have proposed that perceived sleeplessness triggers excessive intention and effort to sleep, ironically disturbing the normal initiation of sleep. The current study tested this specific association between (mis)perception of sleep and intrinsic motivation to think about sleep. METHODS: The sample (n = 74) covered students and community living in Munich and surrounds with ages between 18 and 30 years. We assessed the subjective and objective sleep of participants using a sleep diary and actigraphy. Participants also completed a decision-making task (the pay-per-view task), where they had to decide between thinking about sleep vs. eating. As these options were associated with a variable monetary reward, participants typically experienced a conflict between their preferred topic and the reward for their choice. RESULTS: Multilevel logistic regression analyses showed that participants with greater SOL misperception (i.e., longer subjective relative to objective SOL) forgo a greater reward for the opportunity to think about sleep. LIMITATIONS: The non-clinical nature of our sample may limit the implication of the findings for clinical levels of insomnia. CONCLUSIONS: Results support the cognitive model of insomnia, suggesting that perception of sleeplessness is associated with higher intrinsic motivation to engage in sleep-related thinking.

Pre-Sleep Arousal and Fear of Sleep in Trauma-Related Sleep Disturbances: A Cluster-Analytic Approach.

Background: Trauma-related sleep disturbances constitute critical symptoms of posttraumatic stress disorder (PTSD), but sleep symptoms often reside even after successful trauma-focused psychotherapy. Therefore, currently unattended factors - like fear of sleep (FoS) - might play a crucial role in the development and maintenance of residual sleep disturbances. However, it is unclear whether trauma-exposed individuals exhibit different symptomatic profiles of sleep disturbances that could inform individualized therapeutic approaches and eventually enhance treatment efficacy. Method: In a large online study, a two-step cluster analysis and a hierarchical cluster analysis using Ward's method were performed to explore subgroups among trauma-exposed individuals (N = 471) in terms of FoS, different aspects of trauma-related sleep disturbances (e.g., insomnia symptoms, nightmares, arousal), and PTSD symptoms. These variables were compared between resulting clusters using ANOVAs and Scheffé's post-hoc tests. Results: The hierarchical cluster analysis supported 3- and 4-cluster solutions. The 3-cluster solution consisted of one "healthy" (n = 199), one "subclinical" (n = 223), and one "clinical" (n = 49) cluster, with overall low, medium, and high symptomatology on all used variables. In the 4-cluster solution, the clinical cluster was further divided into two subgroups (n = 38, n = 11), where one cluster was specifically characterized by elevated somatic pre-sleep arousal and high levels of FoS. Conclusions: A subgroup of trauma-exposed individuals with PTSD and sleep disturbances suffers from increased pre-sleep arousal and FoS, which has been suggested as one possible explanation for residual sleep disturbances. In these patients, FoS might be a relevant treatment target.

Impact of childhood maltreatment on obsessive-compulsive disorder symptom severity and treatment outcome.

Background: Preliminary evidence suggests childhood maltreatment to play a causal role in the development and maintenance of obsessive-compulsive disorder (OCD). However, both the effect of childhood maltreatment on the course of OCD treatment and the role of specific subtypes of maltreatment remain largely unknown. Objective: This study aimed to investigate the relationship between childhood maltreatment and the severity and time course of OCD symptoms within a clinical sample of OCD patients (N = 68). We hypothesized that higher levels of childhood maltreatment in OCD patients would be associated with higher symptom severity and worse treatment outcomes. Method: Assessments of childhood maltreatment, OCD symptomatology, and related variables were completed in a sample of OCD patients before and after inpatient treatment as well as at 6 month follow-up. Results: Emotional abuse, sexual abuse and neglect were highly prevalent in our sample. Additionally, the severity of experienced childhood maltreatment was associated with higher OCD symptom severity, with the strongest association found for emotional abuse. Hierarchical linear models indicated that patients with childhood maltreatment showed higher OCD symptom severity at pre-treatment, post-treatment, and follow-up compared to patients without these experiences. However, childhood maltreatment did not moderate symptom improvement during treatment. Conclusion: Thus, although childhood maltreatment is not related to treatment outcome, it is highly prevalent among OCD patients and childhood trauma survivors still show higher OCD symptom severity after treatment. Therefore, childhood maltreatment should be considered in psychological interventions in individuals with OCD.

Antecedentes: Evidencia preliminar sugiere que el maltrato infantil (MI) juega un rol causal en el desarrollo y mantenimiento del trastorno obsesivo-compulsivo (TOC). Sin embargo, el efecto del MI en el curso del tratamiento del TOC y el rol de subtipos específicos de MI persisten siendo ampliamente desconocidos.Objetivo: Este estudio apuntó a investigar la relación entre el MI y la severidad y evolución de la sintomatología de TOC en una muestra clínica de pacientes con TOC (N=68). Planteamos como hipótesis que altos niveles de MI en pacientes con TOC podrían estar asociados con mayor severidad en la sintomatología y peores resultados de tratamiento.Método: Se realizaron evaluaciones de MI, sintomatología de TOC, y variables relacionadas en una muestra de pacientes con TOC antes y después de tratamiento hospitalario así como también a los 6 meses de seguimiento.Resultados: Abuso emocional, abuso sexual y negligencia fueron altamente prevalentes en nuestra muestra. Adicionalmente, la severidad de MI experimentado se asoció con mayor severidad en la sintomatología de TOC, con mayor asociación encontrada para abuso emocional. Modelos lineales jerarquizados indicaron que los pacientes con MI mostraron mayor severidad de sintomatología de TOC antes y después de tratamiento, así como a los 6 meses de seguimiento, en comparación a los pacientes sin MI. Sin embargo, el MI no moderó la mejoría de los síntomas durante el tratamiento.Conclusión: Aunque el MI no está relacionado con el resultado de tratamientos, es altamente prevalente en pacientes con TOC y los sobrevivientes a MI muestran mayor severidad en la sintomatología de TOC aun después del tratamiento. Por lo tanto, el MI debería ser considerado en intervenciones psicológicas en individuos con TOC.

Insomnia-related interpretational bias is associated with pre-sleep worry.

Cognitive models of insomnia highlight the role of biased cognition in sleep-related information, which is proposed to underlie pre-sleep worry, which in turn results in both subjective and objective sleep deficits. To test this hypothesis, the current study investigated interpretational bias, which is a tendency to interpret ambiguous stimuli in a threat-related (here: insomnia-related) manner. We specifically hypothesized that interpretational bias would be associated with (a) pre-sleep worry and (b) poor subjective and objective sleep. Interpretational bias was measured using the ambiguous scenario task, in which participants (n = 76, community sample) were presented with two types of scenarios (insomnia and anxiety related) that could be alternatively interpreted in a neutral manner. Participants additionally completed questionnaires to assess global sleep quality and pre-sleep worry, which were followed by 1-week sleep assessments (via diaries and actigraphy) to estimate specific, daily subjective and objective sleep parameters. The results showed that insomnia-related (but not anxiety-related) interpretational bias was positively associated with pre-sleep worry as well as overall sleep quality. However, these associations could be explained by general trait anxiety. We also found no connection to specific subjective or objective parameters of daily sleep, such as sleep onset latency. These findings support the cognitive-hyperarousal mechanism, where biased cognition (together with trait anxiety) underlies pre-sleep worry. The association with overall sleep quality, but not with specific, daily subjective or objective sleep parameters, may suggest that interpretational bias is specifically relevant for how individuals judge and describe their sleep quality.

Cardiac Vagal Control, Regulatory Processes and Depressive Symptoms: Re-Investigating the Moderating Role of Sleep Quality.

Lower cardiac vagal control (CVC), which is often understood as an indicator for impaired regulatory processes, is assumed to predict the development of depressive symptoms. As this link has not been consistently demonstrated, sleep quality has been proposed as a moderating factor. However, previous studies were limited by non-representative samples, cross-sectional data, and focused on CVC as a physiological indicator for impaired regulatory processes, but neglected corresponding subjective measures. Therefore, we investigated whether sleep quality moderates the effects of CVC (quantified by high-frequency heart rate variability) and self-reported regulatory processes (self- and emotion-regulation) on concurrent depressive symptoms and on depressive symptoms after three months in a representative sample (N = 125). Significant interactions between CVC and sleep quality (in women only), as well as self-/emotion-regulation and sleep quality emerged, whereby higher sleep quality attenuated the relation between all risk factors and current depressive symptoms (cross-sectional data). However, there were no significant interactions between those variables in predicting depressive symptoms three months later (longitudinal data). Our cross-sectional findings extend previous findings on sleep quality as a protective factor against depressive symptoms in the presence of lower CVC and subjective indices of impaired regulatory processes. In contrast, our conflicting longitudinal results stress the need for further investigations.

Cardiac Vagal Control and Depressive Symptoms: The Moderating Role of Sleep Quality.

Lower cardiac vagal control (CVC) has been linked to greater depression. However, this link has not been consistently demonstrated, suggesting the presence of key moderators. Sleep plausibly is one such factor. Therefore, we investigated whether sleep quality moderates the link between CVC (quantified by high-frequency heart rate variability, HF-HRV) and depressive symptoms (assessed using established questionnaires) in 29 healthy women. Results revealed a significant interaction between HF-HRV and sleep quality in predicting depressive symptoms: participants with lower HF-HRV reported elevated depressive symptoms only when sleep quality was also low. In contrast, HF-HRV was not associated with depressive symptoms when sleep quality was high, suggesting a protective function of high sleep quality in the context of lower CVC.

High cardiac vagal control is related to better subjective and objective sleep quality.

Cardiac vagal control (CVC) has been linked to both physical and mental health. One critical aspect of health, that has not received much attention, is sleep. We hypothesized that adults with higher CVC--operationalized by high-frequency heart rate variability (HF-HRV)--will exhibit better sleep quality assessed both subjectively (i.e., with Pittsburgh Sleep Quality Index) and objectively (i.e., with polysomnography). HF-HRV was measured in 29 healthy young women during an extended neutral film clip. Participants then underwent full polysomnography to obtain objective measures of sleep quality and HF-HRV during a night of sleep. As expected, higher resting HF-HRV was associated with higher subjective and objective sleep quality (i.e., shorter sleep latency and fewer arousals). HF-HRV during sleep (overall or separated by sleep phases) showed less consistent relationships with sleep quality. These findings indicate that high waking CVC may be a key predictor of healthy sleep.

Pre- to postsleep change in psychophysiological reactivity to emotional films: Late-night REM sleep is associated with attenuated emotional processing.

Rapid eye movement (REM) sleep has been postulated to facilitate emotional processing of negative stimuli. However, empirical evidence is mixed and primarily based on self-report data and picture-viewing studies. This study used a full-length aversive film to elicit intense emotion on one evening, and an emotionally neutral control film on another evening while psychophysiological and experiential responses were measured. Subsequent sleep was monitored polysomnographically, and specific film scenes were presented again on the next morning. Correlation analyses revealed that participants with longer late-night REM sleep after the aversive film showed higher increase of electrodermal reactivity and less reduction of facial corrugator muscle reactivity to negative film scenes on the next morning. This indicates that REM sleep may be associated with attenuated emotional processing of prolonged and intense emotional stimuli from pre- to postsleep.