Pre-existing sleep problems as a predictor of post-acute sequelae of COVID-19

Several months after COVID-19 many individuals still report persisting symptoms, the so-called 'post-COVID-19 syndrome'. An immunological dysfunction is one of the main pathophysiological hypotheses. As sleep is central to the functioning of the immune system, we investigated whether self-reported pre-existing sleep disturbance might be an independent risk factor for the development of post-COVID-19 syndrome. A total of 11,710 participants of a cross-sectional survey (all tested positive for severe acute respiratory syndrome coronavirus-2) were classified into probable post-COVID-19 syndrome, an intermediate group, and unaffected participants at an average of 8.5 months after infection. The case definition was based on newly occurring symptoms of at least moderate severity and ≥20% reduction in health status and/or working capacity. Unadjusted and adjusted odds ratios were calculated to investigate the association between pre-existing sleep disturbances and subsequent development of post-COVID-19 syndrome while controlling for a variety of demographic, lifestyle, and health factors. Pre-existing sleep disturbances were found to be an independent predictor of subsequent probable post-COVID-19 syndrome (adjusted odds ratio 2.7, 95% confidence interval 2.27-3.24). Sleep disturbances as part of the post-COVID-19 syndrome were reported by more than half of the participants and appeared to be a new symptom and to occur independent of a mood disorder in most cases. Recognition of disturbed sleep as an important risk factor for post-COVID-19 syndrome should promote improved clinical management of sleep disorders in the context of COVID-19. Further, it may stimulate further research on the effect of improving sleep on the prognosis of COVID-19 long-term sequelae and other post-viral conditions.

Changing Sleep Architecture through Motor Learning: Influences of a Trampoline Session on REM Sleep Parameters

Previous research has shown that learning procedural tasks enhances REM sleep the following night. Here, we investigate whether complex motor learning affects sleep architecture. An experiment in which twenty-two subjects either learned a motor task (trampolining) or engaged in a control task (ergometer) was carried out in a balanced within-group design. After an initial laboratory adaptation night, two experimental nights were consecutive. The results indicate that learning a motor task had an effect on REM sleep parameters and, therefore, support the hypothesis that learning a procedural skill is related to an increase in REM sleep parameters. However, the statistical effect on REM sleep is smaller than found in previous studies. One might speculate that the motor learning was not intense enough compared to other studies. For sports practice, the results suggest that REM sleep, which is particularly rich in the morning, plays an important role in motor memory consolidation. Thus, this phase should not be interrupted after complex motor skill learning sessions. In future studies, other motor tasks should be applied.

Seeking help for nightmares: Associated personality factors

Research indicated that patients suffering from nightmares are often undertreated. One reason for this gap is that nightmare sufferers themselves often have not sought professional help for their nightmares, and-if they did-it was not very helpful. The current study aimed at studying trait factors (personality, harm avoidance) in relation to the persons considering seeking professional help. In a population-sample of 1108 persons (712 women, 396 men) with a mean age of 50.55 ± 14.22 years, it was also found that only some of the persons who have problems with nightmares even considered seeking professional help as an option. As expected and after controlling for effects of nightmare frequency, persons with high harm avoidance and high introversion were more likely not seeking help for their problems with nightmares. The associations with low education, low agreeableness and low conscientiousness with considering seeking professional help might point to the fear of stigmatisation in nightmare sufferers. Interestingly, the association between harm avoidance and "Considering seeking professional help" was even stronger in the subsample of frequent nightmare sufferers (once a week or more often). Future efforts should aim at findings new ways to offer adequate help for nightmares and increase the knowledge about nightmare treatment in healthcare professionals.

Chronotype and sensory-processing sensitivity: A cross-sectional survey

Here we examined the possibility of a relationship of sensory processing sensitivity (SPS) with chronotype in a German-speaking sample of N = 1807 (1008 female, 799 male) with a mean age of 47.75 ± 14.41 y (range: 18-97 y). The data were collected using an anonymous online questionnaire (Chronotype: one item of the Morning-Evening-Questionnaire, as well as typical bedtimes on weekdays and weekends; SPS: German version of the three-factor model ; Big Five: NEO-FFI-30) between 21 and 27 April 2021. Results. We found morningness to correlate with the SPS facet low sensory threshold (LST), while eveningness correlated to aesthetic sensitivity (AES) and marginally significant to ease of excitation (EOE). Discussion: The results show that the correlations between chronotype and the Big Five personality traits are not consistent with the direction of the correlations between chronotype and the SPS facets. The reason for this could be different genes that are responsible for the individual traits influence each other differently depending on their expression.

Work-life balance in dreams: Frequency and emotional tone of work-related and hobby-related dreams

As dreams reflect waking life, the so-called continuity hypothesis of dreaming, the literature showing that work-related stress affects dreams negatively is very plausible. As in waking life, hobbies are an important component in the work-life balance. In the present study, the work-life balance in dreams was studied. Overall, 1695 persons (960 women, 735 men; mean age: 53.84 ± 13.99 years) participated in an online survey entitled "Everyday life and dreams". The data collected refer to the pre-pandemic period. The findings indicate that hobby-related dreams are more frequent in persons who often engage in their hobbies, supporting the notion of a thematic continuity. As expected, the emotional tone of hobby-related dreams was more positive compared with dreams in general and work-related dreams in particular. Interestingly, the emotional valence of hobby-related dreams was related to the valence of general emotionality towards work in waking life, supporting the idea of an emotional continuity between waking and dreaming. The work-life balance in dreams could be defined as the difference of the percentages of work-related and hobby-related dreams; it is linked to work-related stress and the hobby frequency, factors similar to those that shift the work-life balance in waking life toward the "work" end of the spectrum.

Nightmare frequency and nightmare distress during the COVID-19 pandemic

STUDY OBJECTIVES

The current study investigated nightmare frequency and distress during the pandemic and associated factors.

METHODS

Participants (n = 1,718) completed a survey, 747 of which were youth. The MADRE dream questionnaire was used to collect self-reported data on nightmare frequency and distress. In addition, personality traits, current stressors, and COVID-related anxiety were also measured. An ordinal regression model was used for statistical analysis, and P < .05 was considered significant.

RESULTS

The findings from this study suggest (1) COVID-related anxiety is associated with the frequency of nightmares and the severity of nightmare distress experienced by a person, and (2) findings support the continuity hypothesis, which suggests waking life experiences are related to nightmares and (3) increased COVID-related anxiety contributes independently to nightmare frequency. COVID-related anxiety appeared to be more prevalent within adults (P < .001, effect size = 0.18) compared to youth. Similar results were found for nightmare distress.

CONCLUSIONS

The risk of nightmares may have increased due to disruptions in mental health and sleep caused by the COVID-19 crisis. These findings may be important in clinician efforts to understand nightmares and the risk of problematic sleep during the pandemic.

CITATION

Remedios A, Marin-Dragu S, Routledge F, et al. Nightmare frequency and nightmare distress during the COVID-19 pandemic. J Clin Sleep Med. 2023;19(1):163-169.

Dream Recall Frequency, Lucid Dream Frequency, and Personality During the Covid-19 Pandemic

Dream recall frequency and lucid dream frequency showed large inter-individual differences that are partly related to personality dimensions. However, as dream research is a small field, independent studies are necessary to build a solid empirical foundation. The present online survey included 1,537 participants (1150 women, 387 men) with a mean age of 35.1 ± 15.8 years. Whereas the relationship between openness to experience and dream recall frequency was in line with previous research - supporting the life-style hypothesis of dream recall, the associations between the Big Five personality factors and lucid dream frequency are less homogenous; for example, the negative relationship between neuroticism and lucid dream frequency. Even though the effect sizes of these associations are small, the findings can help in identifying links between waking and dreaming. Moreover, it was found that lucid dream frequency was related to Covid-19-related worries, whereas dream recall frequency was not.

Dreaming and Sleep-Related Metacognitions in Patients with Sleep Disorders

Sleep-related metacognitions play a role in the etiology of insomnia and are distressing while falling asleep. Although similar concepts, such as thought suppression, have been studied in the context of dreaming, the relationship between sleep-related metacognitions and more negatively toned dreaming due to stressful pre-sleep experiences has yet to be studied. Overall, 919 patients with various sleep disorders completed the Metacognitions Questionnaire-Insomnia (MCQ-I20), Arousal Disposition Scale (APS), and Pre-Sleep Arousal Scale (PSAS) and kept a sleep diary over seven days eliciting dream recall, nightmare frequency, and the emotional tone of their dreams. The regression analysis showed that the MCQ-I20 (small effect size) and the APS (medium effect size) were associated with nightmare frequency and negatively toned dream emotions. These findings suggest that dysfunctional sleep-related metacognitions that are active prior to sleep are also associated with more negatively toned dreaming and more nightmares—even after controlling for trait arousability. It would be very interesting to study where therapeutic strategies, such as metacognitive therapy explicitly targeting sleep-related metacognition, could also be beneficial with regard to dreams (more positive dreams and fewer nightmares).

Dreams, Race, and the Black Lives Matter Movement: Results of a Survey of American Adults

This study considers the relationship between dreaming and race in light of the public protests following the murder of George Floyd on May 25, 2020. Findings are presented from an online survey about dreams and the Black Lives Movement (BLM) gathered from 4,947 demographically diverse American adults sampled between June 15 and June 19, 2020. The results show that the people most likely to have dreams about the public protests were those who support BLM, who are highly educated, and/or who have high dream recall. The dreams themselves tended to be anxious, fearful, and nightmarish, with several recurrent themes: references to George Floyd, participating in protests, threats to one's home, concerns about the pandemic, and conversations about BLM. The findings of this study contribute to a growing research literature showing that dreams, dream recall, and dream sharing can vary significantly depending on people's racial, ethnic, and cultural backgrounds. This study also provides new evidence that dreams have meaningful content relating directly to current events and public affairs. Practical implications for therapists and pastoral counselors are discussed.

Partners and Ex-Partners in Dreams: A Diary Study

Romantic relationships are an important part of human life and thus, according to the continuity hypothesis of dreaming, one’s romantic partner should show up in dreams quite frequently. The present study is based on 1612 dream reports provided by 425 students. The findings confirmed the hypothesis that partner dreams are more frequent than ex-partner dreams and, thus, support the continuity hypothesis of dreaming. Moreover, interactions with ex-partners within the dream were more often negatively toned compared to dreamed interactions with the partner. Unexpectedly, we also found more positive emotions and friendliness in ex-partner dreams compared to partner dreams, indicating that partner dreams are more mundane. To conclude, dreams reflect important aspects of romantic partnerships and their break-ups and, thus, can be very helpful in psychotherapy.

Dreaming in Adolescents During the COVID-19 Health Crisis: Survey Among a Sample of European School Students

According to the continuity hypothesis of dreaming and contemporary psychodynamic approaches, dreams reflect waking life. The aim of the present study was to explore the relationship between the COVID-19 pandemic and dreaming in adolescents. A cross-sectional survey was conducted in Italy, Romania and Croatia involving 2,105 secondary school students (69% girls, mean age 15.6 ± 2.1 years; 31% boys, mean age 15.1 ± 2.2 years; mean age of whole sample 15.4 ± 2.1 years). No substantial differences between countries were found. Thirty-one percent of the participants reported heightened dream recall, 18% noticed an increase in nightmares during the lockdown, and 15% of the provided dreams (n = 498) included pandemic-related content. The results indicate that subjective emotional reactions to lockdown had a significantly higher correlation to dreaming than objective distress (i.e., illness or death of a close one because of COVID-19). These findings suggest that attention to dreams should be included in preventive programs for adolescents with pandemic-related stress.

Ein Fragebogen zur Erfassung von schlafbezogenen Metakognitionen: Deutsche Kurzform des MCQ-I

Hintergrund und Fragestellung

Schlafbezogene Kognitionen, aber auch schlafbezogene Metakognitionen (Umgang mit Gedanken) spielen in der Ätiologie der Insomnie, vor allem bei der Aufrechterhaltung, eine Rolle. Bisher liegt nur ein englischsprachiger Fragebogen (MCQ-I) mit 60 Items zur Erfassung schlafbezogener Metakognitionen vor. Ziel dieser Arbeit war das Zusammenstellen einer kürzeren, deutschen Version, die sowohl gute Reliabilität als auch Validität aufweist.

Material und Methoden

Insgesamt nahmen 512 Patienten mit unterschiedlichen Schlafstörungen (264 Frauen, 248 Männer; mittleres Alter: 45,04 ± 16,70 Jahre) an der Erhebung teil. Der MCQ‑I wurde vor dem Erstgespräch ausgefüllt mitgebracht.

Ergebnisse

Die 20-Item-Version wies eine hohe interne Konsistenz (r = 0,906) und hohe Retest-Reliabilität (r = 0,916) auf. Patienten mit der Diagnose einer Insomnie zeigten einen signifikant höheren Summenwert im MCQ-I 20 als Patienten mit anderen Schlafstörungen. Interessanterweise waren auch die Diagnose einer depressiven Erkrankung und das Auftreten einer Alptraumstörung mit vermehrten schlafbezogenen Metakognitionen verbunden.

Schlussfolgerung

Schlafbezogene Metakognitionen scheinen in der Insomnie-Ätiologie eine Rolle zu spielen. Interessant wäre es zu überprüfen, ob eine rein metakognitive Therapie die Symptomatik bei Insomniepatienten in ähnlicher Weise wie die klassische kognitive Verhaltenstherapie der Insomnie verbessern kann.

Nightmare Distress Questionnaire: associated factors

STUDY OBJECTIVES

The diagnosis of a nightmare disorder is based on clinically significant distress caused by the nightmares, eg, sleep or mood disturbances during the day. The question what factors might be associated with nightmare distress in addition to nightmares frequency is not well studied.

METHODS

Overall, 1,474 persons (893 women, 581 men) completed an online survey. Nightmare distress was measured with the Nightmare Distress Questionnaire.

RESULTS

The findings indicated that nightmare distress, measured by the Nightmare Distress Questionnaire, correlated with a variety of factors in addition to nightmare frequency: neuroticism, female sex, low education, extraversion, low agreeableness, and sensation seeking. Moreover, the percentage of replicative trauma-related nightmares was also associated with higher nightmare distress.

CONCLUSIONS

A large variety of factors are associated with nightmare distress, a finding that is of clinical importance. The construct harm avoidance, however, was not helpful in explaining interindividual differences in nightmare distress. Furthermore, the relationship between nightmare distress and other factors, eg, education or agreeableness, is not yet understood.

Effects of nightmares on the cortisol awakening response: An ambulatory assessment pilot study

Previous studies have reported an association between sleep-related factors such as sleep duration, sleep quality and time of awakening with the cortisol awakening response (CAR). Preliminary evidence suggests that frequent nightmares are associated with a blunted CAR. In the present pilot study we investigated the effect of acute nightmares on the CAR and the cortisol profile of the subsequent day using a within-subject ambulatory assessment study design. Thirty healthy volunteers who reported frequent nightmares enrolled in the study. Over a period of 14 days, salivary samples in addition to sleep-related and state variables were collected at home over the day. Salivary profiles of free cortisol and alpha amylase for up to two days following a nightmare were compared to those following a neutral dream. Overall, mood and health were decreased and the CAR was elevated following nightmares compared to neutral dreams. No differences were found for alpha amylase and for all variables over the remaining part of the day. Results suggest that sleep-related factors such as the occurrence of nightmares account for a certain amount of variance observed in the CAR. This has important methodological implications for CAR studies in general and might have even more relevance for studies in clinical populations suffering from chronic sleep disturbances.

Dreaming about Dogs: An Online Survey

Simple Summary

The findings of the survey indicate that waking-life experiences with dogs (owning a dog or negative experiences with dogs in the past) affect dreaming in a significant way. On the one hand, dog owners dream about dogs more often and had overall positively toned dreams, whereas persons with negative experiences with dogs in their waking life reported a higher percentage of dreams with threatening dogs.

Abstract

Dogs have been close human companions for millennia and one would expect—according to the continuity hypothesis of dreaming—that dogs are also quite common in dreams. Previous studies showed that the percentages of dreams that include dogs range from about 1.5% to 5%, but studies relating waking-life experiences with dogs with dreams about dogs have not been carried out. In total, 1695 persons (960 women, 735 men) completed an online survey that included questions about dreams and waking-life experiences that included dogs. The findings indicate that dogs show up, on average, in about 5% of remembered dreams, but this percentage is much higher in the dreams of dog owners and persons with close contacts with dogs. Moreover, the active time spent with a dog and the proximity during sleep is also related to a higher percentage of dreams that include dogs. Although dreams including dogs are on average more positively toned than dreams in general, about 11% of the dog dreams included threatening dogs. Persons who had negative experiences with dogs in their waking lives reported more threatening dog dreams. The results support the continuity hypothesis and it would be very interesting to conduct content analytic studies with dream samples obtained from dog owners to learn more about the variety of interactions between dreamers and dogs.

Work-Related Dreams: An Online Survey

Professional work is an integral part of modern life. According to the continuity hypothesis of dreaming, which states that dreams reflect waking life, work-related dreams should be quite common. As most dream content analytic studies are carried out in student samples, the topic of work in dreams is understudied. A few small studies indicate that the stress levels associated with the job are especially reflected in work-related dreams. Here, a total of 1695 people (960 women, 735 men) completed an online survey that included questions about the estimated percentage of work-related dreams, the overall emotional tone of work-related dreams, and waking-life experiences related to their current job situation (working or not working). The findings indicate that every fifth dream is related to current or previous work. Individuals who are working dreamed more often about work, with jobs that are experienced as being more stressful being more likely to affect dream content. The emotional tone of work-related dreams was related to stress and the emotions related to work in waking life. Overall, the findings demonstrate that professional life has a profound effect on dreaming in many individuals-even after years. The next steps would be to study the dream content of work-related dreams and relate these contents to specific characteristics about the jobs, e.g., professional field, hierarchical position and autonomy, etc.

Nightmares, Chronotype, Urbanicity, and Personality: An Online Study

Chronotype refers to individual differences in sleep timing ("owls" and "larks") and "eveningness" has been associated with nightmares. However, it has not been tested as to whether neuroticism mediates this relationship. Urbanicity refers to being raised in an urban region and/or currently living in an urban region and is associated with heightened risk for developing mental disorders, and thus might be related to nightmare frequency and nightmare distress. Overall, 2492 persons (1437 women, 1055 men) completed an online survey between 23 March 2015 and 8 April 2015. The mean age of the sample was 47.75 ± 14.41 years. The findings indicate that the previously reported relationship between chronotype and nightmare frequency was mediated by neuroticism and "morningness" was related to higher dream recall compared to persons with a late bedtime preference. Urbanicity was not related to nightmare frequency but to lower nightmare distress, raising the interesting question as to whether beliefs about nightmares might be an important variable that contributes to nightmare distress. Based on the few studies so far, there are still many unresolved questions about the interaction between nightmares, chronotype, and urbanicity.

Interest in telephone nightmare counselling in patients with sleep-related breathing disorders

Background and objective

Nightmares are typically underdiagnosed and undertreated, even though frequent nightmares are quite common in patients with sleep-related breathing disorders. Based on a previous study, we investigated whether patients would respond if they were specifically asked whether they would be interested in telephone counselling about nightmares and nightmare treatment.

Materials and methods

The present study included 537 patients with sleep-related breathing disorders who completed a nightmare questionnaire and—if interested—provided their contact data for a telephone counselling session.

Results

Of the total patients, 5.40% were interested in the telephone counselling. Most of these patients had never sought help for their nightmare condition before. This percentage is much lower than in a previous study, possibly due to the higher time expenditure related to the new consent procedure.

Conclusion

The findings indicate that patients with nightmare problems can be reached with this approach even though they have never sought professional help before. In order to minimize the threshold, it would be desirable to have clinical in-house nightmare counselling, which would not require a detailed study information brochure and informed consent.

Stability of nightmare frequency and its relation to neuroticism: A longitudinal study

Models of nightmare aetiology postulate an interaction between trait and state factors. However, most of the studies that support these models have been cross-sectional and longitudinal studies are scarce. The present data were obtained from N = 888 participants completing two online dream studies carried out independently with the same online panel 2 years apart. Nightmare frequency declined over the 2-year period and these changes were related to changes in neuroticism. The effect of current psychopathology (state aspect) on nightmare frequency was significant but much smaller compared to the effect of previously measured nightmare frequency (trait aspect) and, thus, the study provided empirical evidence for diathesis-stress models. Future longitudinal studies should take a closer look at life events and other factors that increase and/or decrease nightmare frequencies.

0112 Lucid Dreaming Associated with Positive Waking Mood

Introduction

Lucid dreaming (being aware that one is dreaming) is typically a positive experience that may enhance positive mood even after waking. There is concern, however, that lucid dreaming may interfere with sleep quality. In the current experiment, participants practiced common lucid dream induction techniques over the course of a week, and kept a daily sleep and dream diary. The study objective was to assess relationships between dream lucidity and subjective sleep quality, dream emotional content, and subsequent waking mood.

Methods

There were 32 participants aged 19–33 in this open label, single arm study (mean=22.63±3.48; 6 males, 24 females). All participants completed a sleep and dream diary for 7 days that included scaled items (1–7 scale) concerning subjective sleep quality, negative and positive emotional intensity of a dream (if recalled). Participants also completed a 19-item lucidity questionnaire, and the Positive and Negative Affect Schedule. Average scores for the week were computed for all measures and Pearson’s correlations conducted between lucidity and all other measures. Participants with no dream recall (n=5) were excluded. Within-subjects analyses were undertaken by selecting each participant’s highest and lowest lucidity night (n=22; 5 participants with only minimum lucidity excluded).

Results

Positive correlations were found between lucidity and dream positive emotion (r=.490, n=27, p=.009) and positive waking mood (r=.638, n=27, p&lt;.001); there were no other significant correlations (all p&gt;.1). Higher lucidity was associated with more positive dream content (t(21)= -3.214, p=.004) and positive waking mood (t(25)=-4.568, p&lt;.001); no other significant differences were observed.

Conclusion

These data indicate that lucidity is associated with positive dreams and waking mood, with no detriment to self-reported sleep quality. The findings provide preliminary support of lucid dreaming as an intervention to improve wellbeing and mood in the short term.

Support

N/A

Lucid Dreaming and the Feeling of Being Refreshed in the Morning: A Diary Study

REM periods with lucid dreaming show increased brain activation, especially in the prefrontal cortex, compared to REM periods without lucid dreaming and, thus, the question of whether lucid dreaming interferes with the recovery function of sleep arises. Cross-sectional studies found a negative relationship between sleep quality and lucid dreaming frequency, but this relationship was explained by nightmare frequency. The present study included 149 participants keeping a dream diary for five weeks though the course of a lucid dream induction study. The results clearly indicate that there is no negative effect of having a lucid dream on the feeling of being refreshed in the morning compared to nights with the recall of a non-lucid dream; on the contrary, the feeling of being refreshed was higher after a night with a lucid dream. Future studies should be carried out to elicit tiredness and sleepiness during the day using objective and subjective measurement methods.

Fever Dreams: An Online Study

In addition to a large variety of somatic symptoms, fever also affects cognition, sleep, and mood. In an online survey with 164 participants, 100 fever dream reports were submitted. Fever dreams were more bizarre and more negatively toned and included more references to health and temperature perception compared to "normal" most recent dreams - findings that are in line with the continuity hypothesis of dreaming. Future studies should follow up this line of research by conducting diary studies during naturally occurring febrile illnesses and sleep laboratory studies with experimentally induced fever. It would also be very interesting to study the effect of thermal stimulation applied during sleep on dream content. This research helps to understand subjective experiences while sleeping in an extreme condition (elevated body temperature).

Association of Locomotor Activity During Sleep Deprivation Treatment With Response

Disrupted circadian rhythms and sleep patterns are frequently observed features of psychiatric disorders, and especially mood disorders. Sleep deprivation treatment (SD) exerts rapid but transient antidepressant effects in depressed patients and has gained recognition as a model to study quick-acting antidepressant effects. It is of interest how locomotor activity patterns during SD might be associated with and potentially predict treatment response. The present study is an analysis of locomotor activity data, previously collected over a 24 h period, to examine the night of SD (Trautmann et al. 2018) as mood disorder patients suffering from a depressive episode (n = 78; after exclusions n = 59) underwent SD. In this exploratory analysis, the associations between response to SD, locomotor activity, and subjective mood during the 24 h period of SD were explored. Higher levels of activity overall were observed in non-responders (n = 18); in particular, non-responders moved more during the evening of SD until midnight and remained high thereafter. In contrast, activity in responders (n = 41) decreased during the evening and increased in the morning. Subjective mood was not found to be associated with locomotor activity. The window of data available in this analysis being limited, additional data from before and after the intervention are required to fully characterize the results observed. The present results hint at the possible utility of locomotor activity as a predictor and early indicator of treatment response, and suggest that the relationship between SD and locomotor activity patterns should be further investigated.

Social Media, Dreaming, and Personality: An Online Study

Social media consumption plays an important role in everyday life and, thus, one would expect that this topic is reflected in dreams. This online survey included 1,349 participants (763 women, 586 men) completing questions about social media use in waking, percentage of social media dreams, and the Big Five personality dimensions. Social media dreams were quite rare (two percent of all remembered dreams), but their frequency correlated with neuroticism and extraversion-in addition to the amount of time using social media in waking-supporting the hypothesis that social media have a stronger effect on those person's inner life due to the higher importance attached to this channel of communication. For future research it would be of interest to elicit emotions related to social media in waking and the emotional tones of social media dreams to study whether positive and/or negative aspects of waking-life social media use are directly reflected in dreams.

Gender Differences in the Dream Content of Children and Adolescents: The UK Library Study

Although gender differences in the dreams of adults have been studied extensively, large-scale studies in children and adolescents are scarce. The UK Library Study collected 1,995 most recent dreams of children and adolescents. Boys reported more physical aggression and fewer female characters in their dreams, whereas indoor settings were more prominent in girls’ dreams, results that are consistent with the findings in adults and the continuity hypothesis of dreaming. The study indicates that dream content analysis is a valuable tool for studying the inner world of children and adolescents because dreams reflect their waking life experiences, thoughts, and concerns. It would be informative to include measures of waking life aggression, frequency of social contacts, and leisure time activities to provide evidence for direct links between waking and dreaming.

Nightmares and Stress: A Longitudinal Study

STUDY OBJECTIVES

In nightmare etiology, trait and state factors play important roles. However, the interaction of state and trait factors has never been studied in a longitudinal design.

METHODS

The current sample included 406 pregnant women who were followed up approximately 6 months after giving birth (n = 375) and 4 years later (n = 302). A nightmare frequency scale and several stress-related questionnaires were presented at three measurement points.

RESULTS

Despite the major life events in this sample, nightmare frequency was very stable over this time period and decreased slightly. In line with previous findings, cross-sectional analyses showed that stressors were associated with current nightmare frequency but longitudinal analyses indicated that previously measured nightmare frequency showed even stronger effects on current nightmare frequency.

CONCLUSIONS

Because the nightmare frequencies were very stable, it would be desirable to carry out intervention studies treating nightmares as early as possible-even in childhood-and study whether nightmare occurrence is lower even years after the intervention.

CITATION

Schredl M, Gilles M, Wolf I, Peus V, Scharnholz B, Sütterlin M, Bardtke S, Send TS, Samaras A, Deuschle M. Nightmares and stress: a longitudinal study. J Clin Sleep Med. 2019;15(9):1209-1215.

Aetiology and treatment of nightmare disorder: State of the art and future perspectives

This consensus paper provides an overview of the state of the art in research on the aetiology and treatment of nightmare disorder and outlines further perspectives on these issues. It presents a definition of nightmares and nightmare disorder followed by epidemiological findings, and then explains existing models of nightmare aetiology in traumatized and non‐traumatized individuals. Chronic nightmares develop through the interaction of elevated hyperarousal and impaired fear extinction. This interplay is assumed to be facilitated by trait affect distress elicited by traumatic experiences, early childhood adversity and trait susceptibility, as well as by elevated thought suppression and potentially sleep‐disordered breathing. Accordingly, different treatment options for nightmares focus on their meaning, on the chronic repetition of the nightmare or on maladaptive beliefs. Clinically, knowledge of healthcare providers about nightmare disorder and the delivery of evidence‐based interventions in the healthcare system is discussed. Based on these findings, we highlight some future perspectives and potential further developments of nightmare treatments and research into nightmare aetiology.

Psychometric evaluation of the Hamburg Nightmare Questionnaire (HNQ)

Background: Nightmares are a widespread phenomenon. In comparison to the general population, they occur in mentally ill and especially in traumatized individuals with an increased frequency. Despite the high prevalence, there is no short questionnaire in the German language that is able to characterize nightmares, to differentiate between different nightmare types and to assess their impact on daytime functioning. Objective: The Hamburg Nightmare Questionnaire (HNQ) has been developed as a short self-rating instrument to fill this gap. Method: Psychometric characteristics of the HNQ were evaluated in a sample of 707 German soldiers passing through the standard diagnostics of the Center for Mental Health at the German Armed Forces Hospital Hamburg. Results: The results of this study show satisfactory psychometric characteristics as a sound factorial structure and adequate internal consistency for the HNQ as well as initial indications of the construct validity of its subscales. Conclusions: The HNQ is a reliable and economic tool for the assessment of posttraumatic nightmares in clinical as well as research settings.

Nightmare frequency and nightmare distress: Socio-demographic and personality factors

The diagnosis of a nightmare disorder is based on clinically significant distress caused by the nightmares, e.g., sleep or mood disturbances. In order to understand nightmare etiology better empirical research should focus on studying factors that affect nightmare distress in addition to nightmare frequency. Overall, 2492 persons (1437 woman, 1055 men) completed the online survey. Nightmare frequency, global nightmare distress, and personality traits were measured. The findings indicate that in addition to nightmare frequency heightened emotional reactivity measured as neuroticism contribute to global nightmare distress and, thus, supporting the neurocognitive model of Levin and Nielsen (2007). Moreover, the recurring nightmares that relate to a waking-life event were associated with higher nightmare distress. From a clinical viewpoint, it would be desirable to carry out similar surveys using diagnostic interviews in order to determine the presence of a nightmare disorder and study the variables that are related to that diagnosis.

The effect of dream report collection and dream incorporation on memory consolidation during sleep

Collecting dream reports typically requires waking subjects up from their sleep—a method that has been used to study the relationship between dreams and memory consolidation. However, it is unclear whether these awakenings influence sleep‐associated memory consolidation processes. Furthermore, it is unclear how the incorporation of the learning task into dreams is related to memory consolidation. In this study we compared memory performance in a word–picture association learning task after a night with and without awakenings in 22 young and healthy participants. We then examined if the stimuli from the learning task are successfully incorporated into dreams, and if this incorporation is related to the task performance the next morning. We show that while the awakenings impaired both subjective and objective sleep quality, they did not affect sleep‐associated memory consolidation. When dreams were collected during the night by awakenings, memories of the learning task were successfully incorporated into dreams. When dreams were collected in the morning, no incorporations were detected. Task incorporation into non‐rapid eye movement sleep dreams, but not rapid eye movement sleep dreams positively predicted memory performance the next morning. We conclude that the method of awakenings to collect dream reports is suitable and necessary for dream and memory studies. Furthermore, our study suggests that dreams in non‐rapid eye movement rather than rapid eye movement sleep might be related to processes of memory consolidation during sleep.