Lucid dreaming frequency and personality

Provoking lucid dreams at home with sensory cues paired with pre-sleep cognitive training

The ability to realize that you're dreaming - lucid dreaming - has value for personal goals and for consciousness research. One route to lucid dreaming is to first undergo pre-sleep training with sensory cues and then receive those cues during REM sleep. This method, Targeted Lucidity Reactivation (TLR), does not demand extensive personal effort but generally requires concurrent polysomnography to guide cue delivery. Here we translated TLR from a laboratory procedure to a smartphone-based procedure without polysomnography. In a first experiment, participants reported increased lucid dreaming with TLR compared to during the prior week. In a second experiment, we showed increased lucidity with TLR compared to blinded control procedures on alternate nights. Cues during sleep were effective when they were the same sounds from pre-sleep training. Increased lucid dreaming can be ascribed to a strong link formed during training between the sounds and a mindset of carefully analyzing one's current experience.

Frequent Lucid Dreaming Is Associated with Meditation Practice Styles, Meta-Awareness, and Trait Mindfulness

Lucid dreaming involves becoming aware that one's current experience is a dream, which has similarities with the notion of mindfulness-becoming aware of moment-to-moment changes in experience. Additionally, meta-awareness, the ability to explicitly notice the current content of one's own mental state, has also been proposed to play an important role both in lucid dreaming and mindfulness meditation practices. However, research has shown conflicting strengths of associations between mindfulness, meditation, and lucid dreaming frequency, and the link between lucid dreaming and meta-awareness has not yet been empirically studied. This study evaluated the associations between lucid dreaming frequency and different meditation practice styles, mindfulness traits, and individual differences in meta-awareness through an online survey (n = 635). The results suggest that daily frequent meditators experience more lucid dreams than non-frequent meditators. However, weekly frequent meditators did not have a higher lucid dreaming frequency. A positive association was observed between open monitoring styles of meditation and lucid dreaming. The findings also indicate that meta-awareness is higher for meditators and weekly lucid dreamers. Furthermore, frequent lucid dreaming was commonly associated with a non-reactive stance and experiencing transcendence. Overall, the findings suggest a positive relationship between specific meditation practices and lucid dreaming as well as the importance of meta-awareness as a cognitive process linking meditation, mindfulness, and lucid dreaming.

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.

The role of mindful acceptance and lucid dreaming in nightmare frequency and distress

A theoretical and empirical association between lucid dreaming and mindfulness, as well as lucid dreaming and nightmares has previously been observed; however, the relationship between nightmares and mindfulness has received surprisingly little attention. Here, we present the findings of two studies exploring the relation of nightmare frequency and distress with two components of mindfulness, termed presence and acceptance, as well as lucid dreaming. Study 1 (N = 338) consisted of a low percentage of frequent lucid dreamers whereas Study 2 (N = 187) consisted primarily of frequent lucid dreamers that used lucid dream induction training techniques and meditation. Across studies, nightmare-related variables showed a more robust association with mindful acceptance as opposed to mindful presence. Moreover, individuals with high levels of meditation expertise and practice of lucid dreaming induction techniques reported lower nightmare frequency. Finally, in Study 2, which consisted of frequent lucid dreamers, a positive correlation between lucid dreaming frequency and mindfulness was apparent. The present findings support the notion that wakeful mindfulness is associated with the quality of dreams and extend previous research by suggesting a disentangled role of the two facets of mindfulness in dream variation. This association remains open for experimental manipulation, the result of which could have clinical implications.

M, T. F, M. M, A. S, G. H, M. J, L. G, L. B, T. Z. L, B. H, S. R, S. MR. Lucid dreaming increased during the COVID-19 pandemic: An online survey

The COVID-19 pandemic changed people’s lives all over the world. While anxiety and stress decreased sleep quality for most people, an increase in total sleep time was also observed in certain cohorts. Dream recall frequency also increased, especially for nightmares. However, to date, there are no consistent reports focusing on pandemic-related changes in lucid dreaming, a state during which dreamers become conscious of being in a dream as it unfolds. Here we investigated lucid dreaming recall frequency and other sleep variables in 1,857 Brazilian subjects, using an online questionnaire. Firstly, we found that most participants (64.78%) maintained their lucid dream recall frequency during the pandemic, but a considerable fraction (22.62%) informed that lucid dreams became more frequent, whereas a smaller subset (12.60%) reported a decrease in these events during the pandemic. Secondly, the number of participants reporting lucid dreams at least once per week increased during the pandemic. Using a mixed logistic regression model, we confirmed that the pandemic significantly enhanced the recall frequency of lucid dreams (p = 0.002). Such increase in lucid dreaming during the pandemic was significantly associated with an enhancement in both dream and nightmare recall frequencies, as well as with sleep quality and symptoms of REM sleep behavior disorder. Pandemic-related increases in stress, anxiety, sleep fragmentation, and sleep extension, which enhance REM sleep awakening, may be associated with the increase in the occurrence of lucid dreams, dreams in general, and nightmares.

Postural balance in frequent lucid dreamers: a replication attempt

Study Objectives

Early research suggests that the vestibular system is implicated in lucid dreaming, e.g. frequent lucid dreamers outperform others on static balance tasks. Furthermore, gravity-themed dreams, such as flying dreams, frequently accompany lucid dreaming. Nonetheless, studies are scarce.

Methods

We attempted to: (1) replicate previous findings using more sensitive static balance measures and (2) extend these findings by examining relationships with dreamed gravity imagery more generally. 131 participants (80 F; Mage=24.1 ± 4.1 yrs) estimated lucid dreaming frequency then completed a 5-day home log with ratings for dream lucidity awareness, control, and gravity sensations (flying, falling). They then performed balance tasks on a sensitive force plate, i.e. standing on one or both feet, with eyes open or closed. Center of pressure (CoP) Displacement and CoP Velocity on each trial measured postural stability.

Results

Findings partially support the claim of a vestibular contribution to lucid dreaming. Frequent lucid dreamers displayed better balance (lower CoP Velocity) than did other participants on some trials and lucid dreaming frequency was globally correlated with better balance (lower CoP Velocity). Lower CoP Velocity was related to flying sensations in men’s dreams and with more dream control in women’s dreams. However, body height—possibly due to its relationship to sex—and levels of sleepiness confound some of these effects.

Conclusion

While findings only provide a partial replication of previous work, they nonetheless support an emerging view that the vestibular system underlies basic attributes of bodily self-consciousness, such as feelings of self-agency and self-location, whether such consciousness occurs during wakefulness or dreaming.

Case Report: Anomalous Experience in a Dissociative Identity and Borderline Personality Disorder

INTRODUCTION

Dissociative identity disorder, formerly called multiple personality disorder, is a rupture of identity characterized by the presence of two or more distinct personality states, described in some cultures as an experience of possession.

OBJECTIVE

The case of a 30-year-old woman with dissociative identity disorder and borderline personality disorder associated with a previous history of anomalous experience was reported.

CASE REPORT

A 30-year-old woman who fulfilled the DSM-5 criteria for dissociative identity disorder and borderline personality disorder reported the presence of unusual sensory experiences (clairvoyance, premonitory dreams, clairaudience) since she was 5 years old. The patient told that for 12 months she presented episodes in which a "second self" took charge of her actions: she would then speak with a male voice, become aggressive, and require several people to contain her desire for destruction. After 3 months of religious follow-up, and accepting her unusual experiences and trance possessions as normal and natural, she had significant improvement.

CONCLUSION

When approaching DID and BPD patients, it is necessary to observe the anomalous phenomena (in the light of) closer to their cultural and religious contexts, to promote better results in the treatment of their disorders, which has not been explored in the treatment guide.

The overfitted brain: Dreams evolved to assist generalization

Understanding of the evolved biological function of sleep has advanced considerably in the past decade. However, no equivalent understanding of dreams has emerged. Contemporary neuroscientific theories often view dreams as epiphenomena, and many of the proposals for their biological function are contradicted by the phenomenology of dreams themselves. Now, the recent advent of deep neural networks (DNNs) has finally provided the novel conceptual framework within which to understand the evolved function of dreams. Notably, all DNNs face the issue of overfitting as they learn, which is when performance on one dataset increases but the network's performance fails to generalize (often measured by the divergence of performance on training versus testing datasets). This ubiquitous problem in DNNs is often solved by modelers via "noise injections" in the form of noisy or corrupted inputs. The goal of this paper is to argue that the brain faces a similar challenge of overfitting and that nightly dreams evolved to combat the brain's overfitting during its daily learning. That is, dreams are a biological mechanism for increasing generalizability via the creation of corrupted sensory inputs from stochastic activity across the hierarchy of neural structures. Sleep loss, specifically dream loss, leads to an overfitted brain that can still memorize and learn but fails to generalize appropriately. Herein this "overfitted brain hypothesis" is explicitly developed and then compared and contrasted with existing contemporary neuroscientific theories of dreams. Existing evidence for the hypothesis is surveyed within both neuroscience and deep learning, and a set of testable predictions is put forward that can be pursued both in vivo and in silico.

Sleep fragmentation and lucid dreaming

Lucid dreaming-the phenomenon of experiencing waking levels of self-reflection within one's dreams-is associated with more wake-like levels of neural activation in prefrontal brain regions. In addition, alternating periods of wakefulness and sleep might increase the likelihood of experiencing a lucid dream. Here we investigate the association between sleep fragmentation and lucid dreaming, with a multi-centre study encompassing four different investigations into subjective and objective measures of sleep fragmentation, nocturnal awakenings, sleep quality and polyphasic sleep schedules. Results across these four studies provide a more nuanced picture into the purported connection between sleep fragmentation and lucid dreaming: While self-assessed numbers of awakenings, polyphasic sleep and physiologically validated wake-REM sleep transitions were associated with lucid dreaming, neither self-assessed sleep quality, nor physiologically validated numbers of awakenings were. We discuss these results, and their underlying neural mechanisms, within the general question of whether sleep fragmentation and lucid dreaming share a causal link.

Is There a Link Between Frequency of Dreams, Lucid Dreams, and Subjective Sleep Quality?

A lucid dream is a dream in which one is conscious of dreaming and can possibly control the dream or passively observe its unfolding. Frequencies of lucid dreaming (LD), dream with awareness, and dream with actual control were previously investigated in a French student population. As a student population usually differs on oneiric and sleep characteristics (such as sleep quality) from the general population, more investigations were needed. Additionally, it is yet unresolved if LD is related to one's overall sleep quality. This study aims at describing and comparing dream experience frequencies (dream, lucid dreams, awareness, and control) and sleep quality assessed with the Pittsburgh Sleep Quality Index (PSQI) among students (n = 274) and in a general population sample (n = 681). It also aims at evaluating if dream experience frequencies can predict sleep quality across these two samples. Predictive models of PSQI score controlling for age and gender were not significant in the student group while they were all marginally predictive for the general population. However, none of these models showed that the frequency of dream experiences could actually help predict the quality of sleep as the significance of the model was carried over only by the gender variable. These results are discussed in line with previous studies on LD frequencies. Several methodological adjustments for future study are proposed.

Lucid Dreaming, Nightmares, and Sleep Paralysis: Associations With Reality Testing Deficits and Paranormal Experience/Belief

Focusing on lucid dreaming, this paper examined relationships between dissociated experiences related to rapid eye movement (REM) sleep (lucid dreaming, nightmares, and sleep paralysis), reality testing, and paranormal experiences/beliefs. The study comprised a UK-based online sample of 455 respondents (110 males, 345 females, Mean age = 34.46 years, SD = 15.70), who had all previously experienced lucid dreaming. Respondents completed established self-report measures assessing control within lucid dreaming, experience and frequency of nightmares, incidence of sleep paralysis, proneness to reality testing deficits (Inventory of Personality Organization subscale, IPO-RT), subjective experience of receptive psi and life after death (paranormal experience), and paranormal belief. Analysis comprised tests of correlational and predictive relationships between sleep-related outcomes, IPO-RT scores, and paranormal measures. Significant positive correlations between sleep and paranormal measures were weak. Paranormal measures related differentially to sleep indices. Paranormal experience correlated with lucid dreaming, nightmares, and sleep paralysis, whereas paranormal belief related only to nightmares and sleep paralysis. IPO-RT correlated positively with all paranormal and sleep-related measures. Within the IPO-RT, the Auditory and Visual Hallucinations sub-factor demonstrated the strongest positive associations with sleep measures. Structural equation modeling indicated that Auditory and Visual Hallucinations significantly positively predicted dissociated experiences related to REM sleep, while paranormal experience did not. However, paranormal experience was a significant predictor when analysis controlled for Auditory and Visual Hallucinations. The moderate positive association between these variables explained this effect. Findings indicated that self-generated, productive cognitive-processes (as encompassed by Auditory and Visual Hallucinations) played a significant role in conscious control and awareness of lucid dreaming, and related dissociative sleep states (sleep paralysis and nightmares).

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.

Bizarreness of Lucid and Non-lucid Dream: Effects of Metacognition

Dreams are usually characterized by primary consciousness, bizarreness and cognitive deficits, lacking metacognition. However, lucid dreaming (LD) is a type of consciousness state during which the dreamer is aware of the fact that he or she is dreaming, without leaving the sleeping state. Brain research has found that LD shares some common neural mechanisms with metacognition such as self-reflection. With a different metacognition level, the bizarreness of LD would also change. However, the difference in bizarreness between LD and non-LD was seldom explored, and individual differences were often neglected. In the present study, considering LD prevalence in Asia was rarely studied and related results in China and Japan were very different from each other, we first investigated the LD frequency of China in a standardized way. On that basis, we collected dreams of subjects who had relatively higher LD frequency and compared bizarreness density (BD) of LD and non-LD. Moreover, to explore the relationships of metacognition traits and BD, we also measured self-reflection and insight trait by Self-Reflection and Insight Scale. We found that 81.3% of subjects have experienced LD once or more, which is similar to findings in some western countries. Besides, BD was significantly lower in LD than in non-LD. Self-reflection and insight were inversely associated with dream bizarreness. These findings indicate that self-consciousness traits extend from waking to LD and non-LD state. As a particular consciousness state, LD may shed light on the research of consciousness and dream continuity. Future research on dream bizarreness is suggested to take dream types and metacognition differences into consideration.

The cognitive neuroscience of lucid dreaming

Lucid dreaming refers to the phenomenon of becoming aware of the fact that one is dreaming during ongoing sleep. Despite having been physiologically validated for decades, the neurobiology of lucid dreaming is still incompletely characterized. Here we review the neuroscientific literature on lucid dreaming, including electroencephalographic, neuroimaging, brain lesion, pharmacological and brain stimulation studies. Electroencephalographic studies of lucid dreaming are mostly underpowered and show mixed results. Neuroimaging data is scant but preliminary results suggest that prefrontal and parietal regions are involved in lucid dreaming. A focus of research is also to develop methods to induce lucid dreams. Combining training in mental set with cholinergic stimulation has shown promising results, while it remains unclear whether electrical brain stimulation could be used to induce lucid dreams. Finally, we discuss strategies to measure lucid dreaming, including best-practice procedures for the sleep laboratory. Lucid dreaming has clinical and scientific applications, and shows emerging potential as a methodology in the cognitive neuroscience of consciousness. Further research with larger sample sizes and refined methodology is needed.

Lucid Dreaming: Intensity, But Not Frequency, Is Inversely Related to Psychopathology

Lucid dreaming (LD) is awareness that one is dreaming, during the dream state. However, some define and assess LD relying also on controlling dream events, although control is present only in a subset of lucid dreams. LD has been claimed to represent well-being, and has even been used as a therapeutic agent. Conversely, LD is associated with mixed sleep-wake states, which are related to bizarre cognitions, stress, and psychopathology, and have been construed as arousal permeating and disrupting sleep. We propose that previous conflicting findings regarding relations between LD and both psychopathology and well-being, stem from the non-differentiated assessment of frequency and control. The present study aimed to develop an expansive measure of several LD characteristics (the Frequency and Intensity Lucid Dream questionnaire; FILD), and explore their relations with symptomatology. Undergraduate students (N = 187) self-reported trait LD, psychopathology (depression, anxiety, obsessive-compulsive symptoms, dissociation, and schizotypy), stress, and sleep problems; 2 months later, a subsample (n = 78) reported psychopathology again, and also completed a dream diary each morning for 14 days. Preliminary evidence supports the reliability and validity of the FILD. Items converged into four domains: frequency, intensity (e.g., control, activity, certainty of dreaming), emotional valence, and the use of induction techniques. We report an optimal frequency cutoff score to identify those likely to experience LD within a 2-week period. Whereas LD frequency was unrelated to psychopathology, LD intensity, and positive LD emotions, were inversely associated with several psychopathological symptoms. Use of deliberate induction techniques was positively associated with psychopathology and sleep problems. Additionally, we demonstrated directionality by employing a prospective-longitudinal design, showing that deliberate LD induction predicted an increase in dissociation and schizotypy symptoms across 2 months. We conclude that lucidity should not be considered as necessarily suggestive of well-being; LD may be positive or negative, depending on lucidity characteristics. Additionally, deliberate LD induction may harbor negative long-term risk.

Sleep and dream habits in a sample of French college students who report no sleep disorders

There is a lack of up-to-date data on sleep and dream habits of college students. To fill in this gap, we used an online questionnaire sent to the student mailing lists of two major universities of Lyon (Lyon 1 and Lyon 2) for the recruitment of an functional magnetic resonance imaging study with sleep disorders as exclusion criteria. In the sample (1,137 French college students, 411 males, mean age = 22.2 ± 2.4 years, body mass index = 22.0 ± 3.2 kg m^-2 ), on average, the participants reported spending about 8 hr in bed during weekdays, 9 hr during the weekends, and 90.9% of them reported no difficulty falling asleep. Less than 0.4% of students reported to have sleep-walking episodes regularly, but nearly 7% reported regular sleep-talking episodes. The average dream recall frequency was about 3 mornings per week with a dream in mind. Dream recall frequency was positively correlated with the clarity of dream content and the frequency of lucid dreaming, and was negatively correlated with age. Fourteen percent of the students reported frequent lucid dreams, and 6% reported frequent recurrent dreams. We found a gender effect for several sleep and dream parameters, including dream recall frequency and time in bed, both of which were higher in women than in men. We have also observed differences between academic disciplines, namely humanities students (Lyon 2) reported spending more time in bed than sciences students (Lyon 1). These results confirm a gender difference for several sleep and dream parameters, and suggest a link between academic disciplines and sleep duration.

The Fantasy Questionnaire: A Measure to Assess Creative and Imaginative Fantasy

This article reports the construction and validation of a comprehensive self-report measure of fantasy. Unlike previous measures of fantasy, which focus on psychopathology, we conceive fantasy as a trait with positive connotation. Principal component analysis (N = 318) and confirmatory factor analyses (N = 345) were conducted using 2 sociodemographically diverse samples. The results provided support for a 2-factor conceptualization of the construct, with the dimensions imaginative fantasy and creative fantasy. Imaginative fantasy refers to vivid imagination and absorption in these images and daydreams. Creative fantasy refers to the activity of using fantasy to create new ideas. The trait measure showed good internal consistency, test-retest reliability, discriminant and convergent construct validity, as well as incremental validity. Moreover, in 3 behavioral studies, we put fantasy scores in relationship with behavioral data to provide further proof of validity. A comprehensive measure of fantasy can contribute to our understanding of individual differences in inner experiences, creative processes, and problem solving.

Investigating on the Methodology Effect When Evaluating Lucid Dream

Lucid dreaming (LD) is a state of consciousness in which the dreamer is aware that he or she is dreaming and can possibly control the content of his or her dream. To investigate the LD prevalence among different samples, researchers have used different types of methodologies. With regard to retrospective self-report questionnaire, two ways of proceeding seem to emerge. In one case, a definition of LD is given to participants (“During LD, one is–while dreaming–aware of the fact that one is dreaming. It is possible to deliberately wake up, to control the dream action, or to observe passively the course of the dream with this awareness”), while in the other instances, participants are presented separate questions targeting specific LD indicators (dream awareness and dream control). In the present study, we measured LD frequency in a sample of French student in order to investigate for possible disparities in LD frequency depending on the type of questionnaire as outlined above. Moreover, we also study links between the prevalence of LD as assessed, respectively, by each questionnaire with various factors such as Vividness of Mental Imagery and Parasomnia. Results revealed no significant difference between LD frequencies across questionnaires. For the questionnaire with definition (DefQuest), 81.05% of participants reported experience of LD once or more. Concerning the questionnaire based on LD indicators (AwarContQuest), 73.38% of participants reported having experienced LD once or more. However, with regard to the correlations analysis, links between LD prevalence and factors such as Vividness of Mental Imagery and Parasomnia, varied across questionnaires. This result is an argument suggesting that researchers should be careful when investigating links between LD and other factors. The type of methodology may influence findings on LD research. Further studies are needed to investigate on the methodology effect in LD research namely on the respective weight of awareness and control.

Terror and bliss? Commonalities and distinctions between sleep paralysis, lucid dreaming, and their associations with waking life experiences

Sleep paralysis and lucid dreaming are both dissociated experiences related to rapid eye movement (REM) sleep. Anecdotal evidence suggests that episodes of sleep paralysis and lucid dreaming are related but different experiences. In this study we test this claim systematically for the first time in an online survey with 1928 participants (age range: 18–82 years; 53% female). Confirming anecdotal evidence, sleep paralysis and lucid dreaming frequency were related positively and this association was most apparent between lucid dreaming and sleep paralysis episodes featuring vestibular‐motor hallucinations. Dissociative experiences were the only common (positive) predictor of both sleep paralysis and lucid dreaming. Both experiences showed different associations with other key variables of interest: sleep paralysis was predicted by sleep quality, anxiety and life stress, whereas lucid dreaming was predicted by a positive constructive daydreaming style and vividness of sensory imagery. Overall, results suggest that dissociative experiences during wakefulness are reflected in dissociative experiences during REM sleep; while sleep paralysis is related primarily to issues of sleep quality and wellbeing, lucid dreaming may reflect a continuation of greater imaginative capacity and positive imagery in waking states.

The science of consciousness - Basics, models, and visions

This article presents a few models and aspects of the phenomenon consciousness that are emerging from modern neuroscience and might serve as a basis for scientific discourse in the field of Applied Consciousness Sciences. A first model describes the dynamics of information processing in the brain. The evoked electric brain potentials represent a hierarchical sequence of functions playing an important role in conscious perception. These range from primary processing, attention, pattern recognition, categorization, associations to judgments, and complex thoughts. Most functions seem to be implemented in the brain's neural network operating as a neurobiological computer. Another model treats conscious perception as a process of internalisation leading to the "self" as conscious observer. As a consequence, every conscious perception can be seen as a reduced and already interpreted observation of an inner representation of an outer or imagined "world." Subjective experience thus offers properties which can only be experienced from the inside and cannot be made objective. Basic values of humanity such as responsibility, love, compassion, freedom, and dignity can be derived from these subjective qualities. Therefore, in contrast to the Natural Sciences, the Science of Consciousness additionally is challenged to deal with those subjective qualities, emphasizing the resulting influence on health, social interactions, and the whole society.

Meta-Awareness During Day and Night

The present study explored the relationship between lucidity in dreams (awareness of dreams while dreaming) and mindfulness during wakefulness, also considering meditation as a possible moderating variable. An online survey was completed by 528 respondents, of whom 386 (73.1%) had lucid dream experiences. The reported frequency of lucid dreams was found to be positively related to higher dispositional mindfulness in wakefulness. This relationship was only present in those participants who reported acquaintance with meditation. Regarding the dimensions of mindfulness, lucid dream frequency was more strongly associated with mindful presence rather than acceptance. The findings support the notion of an existing relationship between lucidity in dreams and mindfulness during wakefulness, yet it remains unclear whether the relationship is influenced by actual meditation practice or whether it reflects some natural predispositions. Future studies should examine the role of different meditation practices, investigate personality variables that might influence the relationship, and explore how different facets of mindfulness and lucidity interrelate.

Neurobiology and clinical implications of lucid dreaming

Several lines of evidence converge to the idea that rapid eye movement sleep (REMS) is a good model to foster our understanding of psychosis. Both REMS and psychosis course with internally generated perceptions and lack of rational judgment, which is attributed to a hyperlimbic activity along with hypofrontality. Interestingly, some individuals can become aware of dreaming during REMS, a particular experience known as lucid dreaming (LD), whose neurobiological basis is still controversial. Since the frontal lobe plays a role in self-consciousness, working memory and attention, here we hypothesize that LD is associated with increased frontal activity during REMS. A possible way to test this hypothesis is to check whether transcranial magnetic or electric stimulation of the frontal region during REMS triggers LD. We further suggest that psychosis and LD are opposite phenomena: LD as a physiological awakening while dreaming due to frontal activity, and psychosis as a pathological intrusion of dream features during wake state due to hypofrontality. We further suggest that LD research may have three main clinical implications. First, LD could be important to the study of consciousness, including its pathologies and other altered states. Second, LD could be used as a therapy for recurrent nightmares, a common symptom of depression and post-traumatic stress disorder. Finally, LD may allow for motor imagery during dreaming with possible improvement of physical rehabilitation. In all, we believe that LD research may clarify multiple aspects of brain functioning in its physiological, altered and pathological states.

Frequency of Lucid Dreams and Lucid Dream Practice in German Athletes

Mental practice is the cognitive rehearsal of a motor task in the absence of overt physical movement. A different and rather unknown kind of mental rehearsal is practice in lucid dreams. Within lucid dreams, the dreamer is able to control the ongoing dream content and for athletes it is possible to use the dream state to deliberately practice sport skills while physically asleep. In this study, 840 German athletes from various sports were asked about their experience with lucid dreams. About 57% of the athletes stated that they experienced a lucid dream at least once in their lives, 24% are frequent lucid dreamers (having one or more lucid dreams per month), and 9% of the lucid dreamers used this dream state to practice sport skills, and the majority of those athletes had the impression that the rehearsal within the lucid dream improved their performance in wakefulness. The prevalence rate of lucid dreaming in professional athletes is similar as in general population, however the rough estimate of the percentage of lucid dreams compared to all dreams in athletes was found to be nearly twice as high as in general population (14.5% vs. 7.5%). The possibilities of lucid dream practice for professional sports will be discussed.

Lucid dreaming and resilience in the face of exposure to terrorism

The relationship between resilience and lucid dreams, which involves awareness of the experience of dreaming, was examined in 79 Israeli young adults. Psychological distress and lucid dreams 3 years prior to exposure to terrorism, and exposure levels and psychological distress 1 week following exposure, were assessed. Both indirect exposure through media and perceived stress predicted an increase in distress during the 3-year interval under low, but not high, levels of lucid dreams. Possible mechanisms are discussed.

Frequency of Lucid Dreaming in a Representative German Sample

Lucid dreams occur when a person is aware that he is dreaming while he is dreaming. In a representative sample of German adults ( N = 919), 51% of the participants reported that they had experienced a lucid dream at least once. Lucid dream recall was significantly higher in women and negatively correlated with age. However, these effects might be explained by the frequency of dream recall, as there was a correlation of .57 between frequency of dream recall and frequency of lucid dreams. Other sociodemographic variables like education, marital status, or monthly income were not related to lucid dream frequency. Given the relatively high prevalence of lucid dreaming reported in the present study, research on lucid dreams might be pursued in the sleep laboratory to expand the knowledge about sleep, dreaming, and consciousness processes in general.

Unusual sleep experiences, dissociation, and schizotypy: Evidence for a common domain

This paper reviews studies that have examined associations between unusual sleep experiences (including nightmares, vivid dreaming, narcolepsy symptoms, and complex nighttime behaviors) and dissociation and schizotypy. Using correlational studies and structural analyses, evidence is provided that unusual sleep experiences, dissociation, and schizotypy belong to a common domain. It is demonstrated that unusual sleep experiences show specificity to dissociation and schizotypy compared to other daytime symptoms (e.g., anxiety, depression, substance use) and other sleep disturbances (e.g., insomnia, lassitude/fatigue). The paper also outlines the methodological limitations of the existing evidence and makes suggestions for future research. Finally, three models for the overlap of daytime and nighttime symptoms are reviewed, including biological abnormalities, trauma, and personality traits. Although further research is needed, it is suggested that daytime and nighttime symptoms result from problems with sleep-wake state boundaries, which may be precipitated by stress or trauma. In addition, association between daytime and nighttime symptoms can be attributed to the higher order personality trait of Oddity.

Measuring nightmare and bad dream frequency: impact of retrospective and prospective instruments

Studies on nightmare frequency have yielded inconsistent results. We compared the frequency of nightmares and bad dreams obtained with retrospective methods (annual and monthly estimates) and with two types of prospective measures (narrative and checklist logs). Four hundred and eleven participants completed retrospective estimates of nightmare and bad dream frequency and recorded their dreams in either narrative or checklist logs for 2-5 weeks. When measured prospectively with narrative logs, nightmare frequency was marginally higher than the 1-year estimate (P = 0.057) but not significantly different from the 1-month estimate (P > 0.05). Prospective bad dream frequency was significantly greater than the two retrospective estimates (ps < 0.0005). There were no significant differences in the frequency of nightmares and bad dreams reported prospectively with narrative versus checklist logs (ps > 0.05). However, checklist logs yielded a significantly greater number of everyday dreams per week (P < 0.0001). Taken together, the results provide partial support for the idea that when compared to daily logs, retrospective self-reports significantly underestimate current nightmare and bad dream frequency. Prospective studies of dream recall and nightmare frequency should take into account the type of log used, its duration, and the participants' level of motivation over time.

Lucid dreaming treatment for nightmares: a pilot study

BACKGROUND

The goal of this pilot study was to evaluate the effects of the cognitive-restructuring technique 'lucid dreaming treatment' (LDT) on chronic nightmares. Becoming lucid (realizing that one is dreaming) during a nightmare allows one to alter the nightmare storyline during the nightmare itself.

METHODS

After having filled out a sleep and a posttraumatic stress disorder questionnaire, 23 nightmare sufferers were randomly divided into 3 groups; 8 participants received one 2-hour individual LDT session, 8 participants received one 2-hour group LDT session, and 7 participants were placed on the waiting list. LDT consisted of exposure, mastery, and lucidity exercises. Participants filled out the same questionnaires 12 weeks after the intervention (follow-up).

RESULTS

At follow-up the nightmare frequency of both treatment groups had decreased. There were no significant changes in sleep quality and posttraumatic stress disorder symptom severity. Lucidity was not necessary for a reduction in nightmare frequency.

CONCLUSIONS

LDT seems effective in reducing nightmare frequency, although the primary therapeutic component (i.e. exposure, mastery, or lucidity) remains unclear.

Nightmares: from anxiety symptom to sleep disorder

The DSM-IV-TR definition of nightmares-extremely frightening dreams from which the person wakes up directly-is unnecessarily narrow. Other emotions (anger, grief) have also been reported in nightmares, and direct awakening from a bad dream seems to be unrelated to increased distress. In addition, assessment of nightmares is problematic. Polysomnographic recordings have an ameliorating effect on nightmare frequency, retrospective measurements tend to underestimate nightmare frequency, and persons with frequent nightmares may feel reluctant to fill out (daily) prospective measurements. For studying nightmares, it is necessary to distinguish idiopathic nightmares from posttraumatic nightmares, which are part of a posttraumatic stress reaction or disorder that may result from experiencing a traumatic event. Both types of nightmares have been associated with an elevated level of periodic limb movements, although only posttraumatic nightmares seem to be related to more and longer nocturnal awakenings. Nightmares have also been repeatedly associated with the general level of psychopathology, or the so-called personality factor neuroticism. Nightmare distress, the impact on daily functioning caused by nightmares, may function as a mediating variable. Several studies in the last decades have shown that nightmares can be treated with several cognitive-behavioral techniques. The cognitive-restructuring technique imagery rehearsal therapy is the treatment of choice for nightmares, although a randomized controlled trial with an attention control-group has not yet been carried out. Nightmares are more than a symptom of a larger (anxiety) syndrome and need to be viewed from a sleep medicine perspective: nightmares are a highly prevalent and separate sleep disorder that can and should receive specific treatment.