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Measuring consciousness in dreams: The lucidity and consciousness in dreams scale

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  • VITOS Hochtaunus, Köppern, Germany
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... Following the final awakening, participants left the bedroom, PSG was removed, and they completed questionnaires. They first answered the Lucidity and Consciousness in Dreams (Lu-CiD) scale, designed to assess aspects of lucidity in dreams such as memory, insight, control, dissociation, and emotion (Voss, Schermelleh-Engel, Windt, Frenzel, & Hobson, 2013). Though participants ranged from reporting one to four different dreams, they were instructed to respond to the scale with reference to their most lucid or vivid dream. ...
... LuCiD scale. We analyzed LuCiD scores by grouping scale responses into their respective factors (Voss et al., 2013). We compared LuCiD scale scores using Mann-Whitney U tests between experimental groups (7:30 a.m. ...
... There is debate over whether self-report questionnaires-without a direct interrogation of lucidity-are sufficient to capture whether a dream was lucid or not (Baird, Mota-Rolim et al., 2019). The LuCiD scale is one proposed method of quantifying lucidity (Voss et al., 2014(Voss et al., , 2013. To contribute to this discussion, we evaluated whether SVLDs from the current experiment differed in any LuCiD scale factors from non-SVLDs. ...
... The state of lucid dreaming (LD), in contrast, involves the awareness, while experiencing a dream, that one is dreaming. In contrast to non-LD, LD involves multiple cognitive processes including self-reflection, access to waking memories, third-person perspective, capacity for future planning, and ability to control dream content and purposefully awaken oneself (Voss et al., 2009(Voss et al., , 2013. LD has been viewed as a possible avenue to treating dream disturbances in certain mental disorders, including posttraumatic stress disorder (PTSD; Macêdo et al., 2019). ...
... If posttraumatic lucid nightmares conform to Stumbrys' (2018) definition of a lucid nightmare (nightmare awareness, accompanied by negative emotion, absent plot control, and inability to purposefully awaken), they would be expected to evoke nightmare distress. A more comprehensive understanding of the constructs associated with posttraumatic lucid nightmares can be gathered with the Lucidity and Consciousness in Dreams Scale (LuCiD; Voss et al., 2013), which characterizes lucid dreams along several dimensions: insight, thought, control, dissociation, realism, memory, negative emotion, and positive emotion (Voss et al., 2013). ...
... If posttraumatic lucid nightmares conform to Stumbrys' (2018) definition of a lucid nightmare (nightmare awareness, accompanied by negative emotion, absent plot control, and inability to purposefully awaken), they would be expected to evoke nightmare distress. A more comprehensive understanding of the constructs associated with posttraumatic lucid nightmares can be gathered with the Lucidity and Consciousness in Dreams Scale (LuCiD; Voss et al., 2013), which characterizes lucid dreams along several dimensions: insight, thought, control, dissociation, realism, memory, negative emotion, and positive emotion (Voss et al., 2013). ...
... There is a consensus in describing LD as a continuum with different degrees of consciousness rather than a dichotomic experience (e.g., Barrett, 1992;Stumbrys et al., 2012;Gasca and García-Campayo, 2017). In this regard, Voss et al. (2013) defined lucid dreaming as hybrid states of consciousness in which part of the brain operates in the primary mode, while another part has access to secondary consciousness (i.e., the dreamer is aware of the fact that he/she is dreaming while the dream continues). Independent laboratories have validated the existence of LDs by identifying their neurophysiological correlates and showing distinct patterns of brain activation that supports the hypothesis of hybrid states with elements of primary and secondary consciousness modes (e.g., Voss et al., 2009Voss et al., , 2014Dresler et al., 2012). ...
... To measure and assess major and minor determinants of LDs, Voss et al. (2013) developed the Lucidity and Consciousness in Dreams scale (LuCiD) based on theoretical considerations and empirical observations. The authors identified eight factors, primarily based on the work by LaBerge and DeGracia (2000) and Kahn (2007), from an exploratory analysis that was validated using confirmatory analysis. ...
... It was subsequently reduced to 24 items in a second version before the addition of four new items regarding positive and negative emotion, specifically. The final validated LuCiD comprises 28 items distributed across eight factors involved in LD consciousness that can best be described by them (Voss et al., 2013;Voss and Hobson, 2015): (1) lucid insight (Insight; α = 0.91) into the fact that what one is currently experiencing is not real but only a dream; (2) control over thought and actions in dreams (i.e., control over dream plot; Control; α = 0.90); (3) logical thought about other dream characters (Thought; α = 0.82), (4) perceptual realism (Realism; α = 0.79) pertaining to the similarity between emotions, thoughts and events, with wakefulness as judged after awakening from the dream; (5) memory access to elements of waking life (Memory; α = 0.66); (6) experiencing the dream from a third person perspective (Dissociation; α = 0.56); (7) negative emotion (Negative emotion; α = 0.68); and (8) positive emotion (Positive emotion; α = 0.87). The eight-factor model was supported by exploratory and confirmatory factorial analyses where the leading factor was insight, followed by thought, control, positive emotion, and dissociation. ...
Article
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Lucid dreaming, a specific phenomenon of dream consciousness, refers to the experience being aware that one is dreaming. The primary aim of this research was to validate a Spanish version of the Lucidity and Consciousness in Dreams scale (LuCiD). A secondary aim was to explore whether meditation experience and mindfulness trait were related to LuCiD scores. Data from 367 Spanish men (34.6%) and women (65.4%) who completed LuCiD, the Five Facets of Mindfulness Questionnaire (FFMQ), and the Positive and Negative Affect Schedule (PANAS) were examined. From the total sample, 40.3% indicated some experience with formal meditation (meditators), while 59.7% did not have any meditation experience (non-meditators). A random subsample of 101 participants, who completed LuCiD for a second time after a period of 10-15 days, was used for test-retest reliability analysis. The LuCiD scale comprises 28 items distributed across eight factors: insight, control, thought, realism, memory, dissociation, negative emotion, and positive emotion. Factor structure, reliability by both internal consistency and test-retest reliability, and construct and concurrent validity were tested. Confirmatory factor analysis (CFA) confirmed the original eight-factor model, showing goodness of fit in contrast to a single-factor model. Item 15 was deleted from the Dissociation factor as it performed poorly (i.e., skewness and kurtosis, non-normal distribution of responses, and corrected item-total correlation under 0.40). The scale showed adequate values of internal consistency (between α = 0.65 for Memory and α = 0.83 for Positive Emotion) and test-retest reliability by significant Pearson correlations (p < 0.001) for each factor. The scores of meditators were higher for the LuCiD scale Insight and Dissociation factors, in contrast to those of non-meditators. The Observing facet of mindfulness was positively associated with all LuCiD factors, except Realism and Positive Emotion, and the Acting with Awareness facet showed a negative correlation with the LuCiD factor Realism. Finally, positive and negative affects was associated with the LuCiD factors Positive Emotion and Negative Emotion. This study provides a valid and reliable measure for exploring lucidity and consciousness García-Campayo et al. Spanish Validation of LuCiD Frontiers in Psychology | www.frontiersin.org 2 October 2021 | Volume 12 | Article 742438 in dreams for a Spanish population, Moreover, the results suggest a relationship with meditation experience, mindfulness trait, and positive and negative affect.
... The fictional space of the dream appears to be unsorted in its symbolic character, partly irrational and bizarre (Hobson, Pace-Schott & Stickgold, 2000;Kahn & Gover, 2010). Usually, the dreamer is not able to think logically, make decisions and act intentionally (Voss, Schermelleh-Engel, Windt, Frenzel & Hobson, 2013). According to Hobson (2009), dreams are predominantly related to the level of primary consciousness, which is subject to laws of perception and feeling. ...
... Lucid dreaming is defined as the ability to become aware of the fact that one is still asleep (Gackenbach, 1991;LaBerge & Rheingold, 1990;Voss & Hobson, 2015). Other characteristics of lucid dreaming are: exercising control over the plot of the dream, perceiving dissociative thought as a third person in an extended sense, having memories of one's waking life, making decisions and being able to decide to stay in the dream instead of waking up (Dresler et al., 2011;Holzinger, LaBerge & Levitan, 2006;Voss et al, 2013). Thus, lucid dreaming is a hybrid state in which otherwise predominant secondary consciousness from the waking state is actively included. ...
... After the interview, participants were asked to fill out a paper-based version of the Lucidity and Consciousness in Dreams Scale (LuCiD; Voss et al., 2013). Participants with lucid dream experiences had to use a recent lucid dream as the basis for their answers. ...
Article
Synaesthesia is a phenomenon in which the stimulation of one sensory modality automatically and consistently over time evokes a sensation in the same or a different modality in an idiosyncratic manner. In addition to pure sensory coupling, synaesthetes are characterized by cognitive peculiarities, such as abnormalities in perception, creativity, advantages in vocabulary, and vivid imagery. The present work is concerned with the question of the extent to which synaesthetes’ unusual perception is reflected in the dream state. Little is known about synaesthetes’ dreaming behaviour. Dreams are equated with the unconscious processing of the mind. An exception is a lucid dream, in which one is aware of their dreaming. In this dissociative state, it is possible to establish a connection to one's waking reality, wake up in a targeted manner, and control dream actions. Through self-report measures, participants (N=31 grapheme-colour-synaesthetes; N=32 non-synaesthetes) indicated their dream experiences and completed the Lucidity and Consciousness in Dreams scale (LuCiD scale). Synaesthetes reported lucid dream experiences significantly more often than non-synaesthetes. Qualitative differences were not found between both groups’ lucid dreamers. The two groups of lucid dreamers reported a majority of highly frequented lucidity. In addition, an association was identified between the early onset of lucid dreaming and higher values of the LuCiD scale. The results are discussed regarding the relevance of lucidity in synaesthesia within the context of consciousness research.
... The fictional space of the dream appears to be unsorted in its symbolic character, partly irrational and bizarre (Hobson, Pace-Schott & Stickgold, 2000;Kahn & Gover, 2010). Usually, the dreamer is not able to think logically, make decisions and act intentionally (Voss, Schermelleh-Engel, Windt, Frenzel & Hobson, 2013). According to Hobson (2009), dreams are predominantly related to the level of primary consciousness, which is subject to laws of perception and feeling. ...
... Lucid dreaming is defined as the ability to become aware of the fact that one is still asleep (Gackenbach, 1991;LaBerge & Rheingold, 1990;Voss & Hobson, 2015). Other characteristics of lucid dreaming are: exercising control over the plot of the dream, perceiving dissociative thought as a third person in an extended sense, having memories of one's waking life, making decisions and being able to decide to stay in the dream instead of waking up (Dresler et al., 2011;Holzinger, LaBerge & Levitan, 2006;Voss et al, 2013). Thus, lucid dreaming is a hybrid state in which otherwise predominant secondary consciousness from the waking state is actively included. ...
... After the interview, participants were asked to fill out a paper-based version of the Lucidity and Consciousness in Dreams Scale (LuCiD; Voss et al., 2013). Participants with lucid dream experiences had to use a recent lucid dream as the basis for their answers. ...
... Para el estudio de los SL se han desarrollado técnicas neurofisiológicas como polisomnografía durante la cual se instruye a sujetos para que durante el SL desarrollen una acción tangible como es el movimiento ocular en una secuencia preestablecida o el control de la respiración [6] dado que REM es la etapa más relacionada con producción onírica [7]. En el SL la actividad cerebral aumenta, especialmente en la parte de la corteza prefrontal, el área que permite la autorreflexión y que estaría alterada en los esquizofrénicos [8]. Esa área es más grande en los soñadores lúcidos [9] y estaría relacionada con la capacidad humana de autorreflexión, que se conoce como metacognición. ...
... La escala Lucidity and Consciousness into Dreaming (LuCID) desarrollada por Ursula Voss en el año 2013 [8], cuenta con 28 items, analizándose 8 subescalas. Cada pregunta posee una puntuación de 0 a 5, refiriéndose de menor a mayor posibilidad de tener SL. ...
... Las preguntas fueron dirigidas a "el soñador" , sin realizar diferencias de género en el texto. En cuanto a las subescalas son 8 y son: introspección (conformado por las preguntas # 1, 3,8,9,16,19); control (# 4, 6,10, 14,23); pensamientos (# 5, 12,22); realismo (# 7, 17,20); memoria (# 2, 13,18, 24); disociación (# 11, 15,21); emoción positiva (# 25,27) y emoción negativa (# 26,28) Si los valores eran bajos, en toda la lista, se considera como los soñadores, tenían sueños "normales". Las subescalas que definen SL según Voss son 5 como: introspección, pensamiento, control, disociación, emoción positiva. ...
Article
Introduction: It is called lucid dreaming, when the dreamer is aware that he is dreaming and can control the dream content. We lack Spanish-speaking tools that assess the presence of lucid dreams, so our objectives were to carry out the adaptation to Spanish and cross-cultural interpretation of the Lucidity and Consciousness in Dreams Scale (LuCID) and to evaluate the presence of lucid dreamers. Material and methods: Cross-sectional study, carried out by means of translation and retro-translation of the LuCID scale. The ethics committee approved it with number 3359. Results: 220 surveys, N = 216 were chosen. Age of subjects who completed: 18-76 (mean: 47) years. Women: n = 146 women. Countries: Argentina and Mexico were the ones that mostly participated. The mean and standard deviation of the analyzed subscales were: control: 2.82 / 1.1; introspection: 2.79 / 1.1; positive emotion: 2.66 / 1.3; dissociation: 2.62 / 1.3; memory: 2.51 / 1.1; thoughts: 2.44 / 1.3; realism: 2.34 / 1.2; negative emotion: 2.22 / 1.3. Of those surveyed, 56 individuals (24.5%) presented higher scores on the subscales for lucid dream diagnosis. Conclusion: The transcultural adaptation and interpretation of the lucidity and consciousness in dreams scale (LuCID) was carried out, which allowed us to detect almost a third of lucid dreamers. This scale should be validated in a select population of lucid dreamers for use.
... Thomas et al. (2015) indicated a higher prevalence of positive emotions in dreams with awareness versus dreams without awareness. Similar studies (LaBerge et al., 2018;Schädlich & Erlacher, 2012;Voss et al., 2013) showed that lucid dreams were rated more positively and tend to feature more positive emotional content compared to nonlucid dreams. This would reflect the fact that the lucid dreamers tends to choose pleasant activities if they are able to control the dream. ...
... Furthermore, lucidity levels are positively correlated with dream bizarreness (Mallett et al., 2021). However, several studies (Gackenbach & Schillig, 1983;Stocks et al., 2020;Voss et al., 2013;Yu & Shen, 2020) found no differences in relation to bizarreness between lucid, ordinary, and vivid dreams. The within-subject study (Yu & Shen, 2020) might indicate that lucid dreams might not be more bizarre than nonlucid dreams within the same person, that is, that dream bizarreness might be related to individual differences, for example, metacognitive traits and self-reflection. ...
... The results of the present study demonstrated that lucid dream reports contain more positive emotions compared to nonlucid dreams thereby confirming previous findings (LaBerge et al., 2018;Schädlich & Erlacher, 2012;Voss et al., 2013). Compatible with this finding, lucid dream reports also included fewer problems, less receiving of verbal aggression, and fewer death themes. ...
... The majority of these studies have been conducted in awake people through methods that manipulated the phenomenal awareness of stimuli in an all-or-none manner (e.g., Lamme and Roelfsema, 2000;Dehaene et al., 2003). However, consciousness is gradual rather than dichotomous (Schooler, 2002;Overgaard et al., 2006;Kouider et al., 2010;Voss et al., 2013;Bayne et al., 2016). The gradualness of consciousness is revealed by dreams that are associated with different levels of lucidity, thereby reflecting various states of consciousness (Moss, 1986;Revonsuo, 1995). ...
... Lucid dreamers exhibit metacognition and self-awareness-the core characteristics of secondary consciousness. Lucid dreaming has been argued to be a hybrid state of consciousness (Voss et al., 2013) that cannot be dichotomously categorized into primary or secondary consciousness. ...
... To differentiate consciousness states associated with dreams and identify the core characteristics of lucid dreams, Voss et al. (2013) developed a self-reported questionnaire, namely the Lucidity and Consciousness in Dreams scale (LuCiD scale), to examine dreamers' memory of their dreams. Voss et al. (2013) and Voss et al. (2018) identified eight factors to construct the LuCiD scale, among which the factors of insight, control, thought, memory, dissociation, and positive emotion differentiated lucid dreams from non-lucid dreams. ...
Article
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This study investigated the relationship between dream lucidity, i.e., a dreamer’s insight to the ongoing dream, and attention by considering lucidity as a trait. We examined the ways in which lucidity correlates with the orienting, alerting, and conflict components of the attentional network. A total of 77 participants rated the lucidity of their dreams over 7 consecutive days with the LuCiD scale and then completed the attentional network task (ANT). A negative correlation between trait lucidity and the conflict score of the ANT was found for 49 participants whose responses were faster when an alerting signal was presented. This result suggested that, with a prerequisite that the presence of cues facilitates subsequent information processing, the greater a person’s trait lucidity, the more efficiently he or she is capable of resolving conflicts.
... In another vein, lucid dreaming, which is defined as the experience of knowing one is dreaming while one is dreaming (LaBerge, 1985), has also been described as a transcendent experience linked to wellbeing, increased selfconfidence, psychological resilience, and positive emotions (Soffer-Dudek, 2020). Lucid dreaming is considered a hybrid state of consciousness in which part of the brain operates in the primary mode, while another part has access to secondary consciousness (Stumbrys et al., 2012;Voss et al., 2013). Research indicates that around 55% of adults have experienced at least one lucid dream, while 23% experience them frequently (Saunders et al., 2016). ...
... The Lucidity and Consciousness in Dreams Scale (LUCID; Voss et al., 2013) is a 28-item questionnaire that assesses key aspects of dream lucidity in detail regarding one recent dream that the respondent has to choose. LUCID presents 8 subscales: insight, control, thought, realism, memory, dissociation, negative emotion, and positive emotion. ...
... As far as dream lucidity is concerned, two tendencies close to significance were observed in the two LUCID subscales of "thought" and "dissociation, " reflecting higher scores for meditators. The first refers to logical thought about other dream characters (e.g., "while dreaming, I often thought about my own actions"), while "dissociation" refers to experiencing the dream from a third person's perspective (e.g., "I watched the dream from the outside, as if on a screen") (Voss et al., 2013). In a similar line, a previous study (García-Campayo et al., 2021) observed that the meditators scored more highly for the "insight" and "dissociation" factors and reported that length of meditation experience was significantly associated with "control" and "dissociation" (i.e., higher scores for more meditation experience). ...
Article
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The aim of this study was to compare meditators and nonmeditators in terms of their tendency to have peak experiences and their dream lucidity, while examining the associations between these outcomes and some related variables such as nondual awareness, mindfulness facets and absorption. In this cross-sectional study, 237 participants from general Spanish population completed an online survey that included ad hoc questions related to the study aim, along with the Five Facet Mindfulness Questionnaire (FFMQ), the Nondual Embodiment Thematic Inventory (NETI), the Tellegen Absorption Scale (TAS) and the Lucidity and Consciousness in Dreams Scale (LUCID). Of the total, 110 participants were identified as meditators and 127 as nonmeditators. More than half of the sample (58.2%) reported having experienced at least one peak experience in their life; these showed no differences in the number, intensity, or self-inducing ability of these experiences between both groups but were significantly more common among meditators (71.8% vs. 46.8%; p<.001), who also presented higher scores in most of the questionnaires, except for some LUCID subscales. Regression models demonstrated that being a meditator was a significant predictor of having had a peak experience, but not of LUCID scores. These results, which need to be interpreted considering the study limitations, support the potential of meditation to facilitate having peak experiences, while its impact on lucid dreams remains unclear.
... One night in the first week of the study and three consecutive nights in the last week were recorded with home-based polysomnography (SOMNOscreen, SOMNOmedics, Germany). After each polysomnography, participants filled out the LuCiD questionnaire [10] in addition to the DLQ. All participants were instructed to verify any lucid dreams during polysomnography with eye signal verification [11], i.e. moving their eyes left-right-left-right if they realized they were dreaming. ...
... For the DLQ, only the items associated with the main lucidity factor were used for further analysis (see [9]). Likewise for the LuCiD, only items associated with the main dream insight factor were used (see [10]). Failure to recall a dream upon awakening was treated as 'missing data' for the purpose of analysis, as were any aberrant cases such as parasomnia. ...
... B 376: 20190697 have their origins in the vestibular system as reported for older systems [21], but might be interpreted as a novelty effect given that our participants were VR novices. Potentially dissociogenic effects of VR, described in the literature and anecdotally reported in our study as well, are in line with previous descriptions of links between lucid dreaming and state dissociation [10,[22][23][24][25], lucid dreaming and the prefrontal cortex [26][27][28]), and clinical dissociation and the prefrontal cortex [29,30]. Lucid dreaming has been shown to occur with stronger dream control in patients with bipolar disorders and schizophrenia ( [31]; but see [32]), which include dissociative and depersonalization-like symptoms as part of their central pathology [33][34][35]. ...
Research
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Metacognitive reflections on one's current state of mind are largely absent during dreaming. Lucid dreaming as the exception to this rule is a rare phenomenon; however, its occurrence can be facilitated through cognitive training. A central idea of respective training strategies is to regularly question one's phenomenal experience: is the currently experienced world real , or just a dream? Here, we tested if such lucid dreaming training can be enhanced with dream-like virtual reality (VR): over the course of four weeks, volunteers underwent lucid dreaming training in VR scenarios comprising dream-like elements, classical lucid dreaming training or no training. We found that VR-assisted training led to significantly stronger increases in lucid dreaming compared to the no-training condition. Eye signal-verified lucid dreams during polysomnography supported behavioural results. We discuss the potential mechanisms underlying these findings, in particular the role of synthetic dream-like experiences, incorporation of VR content in dream imagery serving as memory cues, and extended dissociative effects of VR session on subsequent experiences that might amplify lucid dreaming training during wakefulness. This article is part of the theme issue ‘Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation'.
... More modern approaches to measuring lucidity include a variety of questionnaires based on indirect measures of dream awareness, such as levels of insight or self-reflectiveness (Dresler et al., 2014;Kahan & LaBerge, 2011;Kahan & Sullivan, 2012;Lee & Kuiken, 2015;Voss et al., 2013). To-date, the current focus of these scales has not been to quantify the variation within lucid dreams, but rather to strictly contrast lucid versus non-lucid dreams or waking. ...
... To-date, the current focus of these scales has not been to quantify the variation within lucid dreams, but rather to strictly contrast lucid versus non-lucid dreams or waking. Voss et al. (2013) used a 6-point Likert scale ranging from Strongly disagree (0) to Strongly agree (5), with probes such as "While dreaming, I often asked myself whether I was dreaming. " Factor analysis on these 28 probes revealed that lucid dreams contained more insight, control, thought, memory, dissociation, and positive emotion than non-lucid dreams. ...
... With the current study, we propose that an additional line of investigation should be into the non-binary expression of dream awareness within lucid dreams (see also Mota-Rolim et al., 2010;Noreika et al., 2010;. Though several existing questionnaires use a continuous scale in measuring lucidity (e.g., Stumbrys et al., 2013;Voss et al., 2013), they are almost exclusively used to bin dreams into a dichotomous lucid or non-lucid categorization. Emphasizing the full distribution of scores on these or novel scales might provide more sensitive insight into what induces lucidity and how lucidity impacts waking life. ...
Article
Full-text available
Dream lucidity, or being aware that one is dreaming while dreaming, is not an all-or-none phenomenon. Often, subjects report being some variant of “a little lucid” as opposed to completely or not at all. As recent neuroimaging work begins to elucidate the neural underpinnings of lucid experience, understanding subtle phenomenological variation within lucid dreams is essential. Here, we focus on the variability of lucid experience by asking participants to report their awareness of the dream on a 5-point Likert scale (from not at all to very much). Participants implemented a combination of mnemonic training lucid dream induction methods at home for one week and provided detailed reports about their dream experiences each morning. Consistent with previous research, cognitive induction methods led to about half of participants reporting at least one lucid dream and about half of all dreams including some level of lucidity. However, we also show that induction success rate varies significantly depending on the minimum criteria for lucidity. Participants also reported how much they adhered to specific components of each induction method, and the amount of mnemonic rehearsal during a brief early awake period was predictive of lucidity level. Furthermore, lucidity levels were positively correlated with dream control, dream bizarreness, and next-morning positive affect. Lastly, we asked participants open-ended questions about why they chose particular levels of lucidity. We focus a qualitative discussion on responses to those “semi-lucid” dreams (rated just a little, moderately, or pretty much lucid) to explore why participants rate their dreams as having intermediate levels of awareness. Together, the present study explores the frequency of semi-lucid dreams, what they are, why they might arise, their correlates, and how they impact methodological concerns in lucid dreaming research.
... More modern approaches to measuring lucidity include a variety of questions 58 based on indirect measures of dream awareness, such as levels of insight or self-59 reflectiveness (Dresler et al., 2014;Kahan & LaBerge, 2011;Kahan & Sullivan, 2012;Lee 60 & Kuiken, 2015;Voss et al., 2013). To-date, the current focus of these scales has not 61 been to quantify the variation within lucid dreams, but rather to strictly contrast lucid 62 versus non-lucid dreams or waking. ...
... To-date, the current focus of these scales has not 61 been to quantify the variation within lucid dreams, but rather to strictly contrast lucid 62 versus non-lucid dreams or waking. Voss et al. (2013) used a 6-point Likert scale ranged 63 ...
... Most responses included certain limitations of 322 lucidity, such as a lack of control, or a fleeting lucidity that appeared only at the beginning 323 or end of the dream. The current definition of lucid dreaming does not include dream 324 control (Baird et al., 2019), although dream control is typically higher in lucid than non-325 lucid dreams (LaBerge et al., 2018;Voss et al., 2013). Also note that van Eeden's original 326 description of lucid dreams included dream control elements (van Eeden, 1913 Viewing only the Likert responses to I was aware that I was dreaming suggests 330 that lucidity falls along a true continuum, and that further variation in response options 331 might capture more of it. ...
Preprint
Dream lucidity, or the real-time awareness of a dream, is not an all-or-none phenomenon. Often, subjects report being some variant of “a little lucid” as opposed to completely or not at all. As recent neuroimaging work begins to elucidate the neural underpinnings of lucid experience, understanding subtle phenomenological variation within lucid dreams is essential. Here, we focus on the variety of lucid experience by asking participants to report their awareness of the dream on a 5-point Likert scale (from not at all to very much). Participants implemented lucid dream induction methods at home for one week and provided detailed reports about their dream experiences each morning. Consistent with previous research, cognitive induction methods led to about half of participants reporting at least one lucid dream and about half of all dreams including some level of lucidity. However, we also show that induction success rate varies significantly depending on the minimum criteria for lucidity. Participants also reported how much they adhered to specific components of each induction method, and the amount of mnemonic rehearsal during a brief early awake period was predictive of lucidity level. Furthermore, lucidity levels were positively correlated with dream bizarreness and next-morning positive affect. Lastly, we asked participants open-ended questions to interrogate why they chose particular levels of lucidity. We focus a qualitative discussion on responses to those “semi-lucid” dreams (rated just a little, moderately, or pretty much lucid) to explore why participants rate their dreams as having middle levels of awareness. Together, the present study explores the frequency of semi-lucid dreams, what they are, why they might arise, their correlates, and how they impact methodological concerns in lucid dreaming research.
... The awareness of consciousness in dreams varies gradually (Voss et al., 2013;Bayne et al., 2016;Sanz Perl et al., 2021) and can be measured on a spectrum of lucidity (LaBerge & DeGracia, 2000). On one end of the spectrum, dreamers in nonlucid dream states are unaware that they were dreaming. ...
... Lucid dreams predominantly occur during rapid eye movement (REM) sleep but have also been observed during the N1 and N2 sleep stages (La Berge et al., 1981;LaBerge et al., 1986;Mota-Rolim et al., 2015;Baird et al., 2019). Lucid dreamers can think logically, control the narrative of the dream, and retrieve memories of events they experienced when they were awake (LaBerge, 1990;Voss et al., 2013). A hypothesis on the distinction between primary and secondary consciousness (Edelman, 2003) suggested that nonlucid dreams are associated with primary consciousness in which perceptual and motor events are integrated with memory to construct a multimodal scene in the present. ...
... A hypothesis on the distinction between primary and secondary consciousness (Edelman, 2003) suggested that nonlucid dreams are associated with primary consciousness in which perceptual and motor events are integrated with memory to construct a multimodal scene in the present. Lucid dreams are associated with both primary and secondary consciousness, which comprises meta-awareness, self-reflection, and decision-making (Voss et al., 2013). The degree of an individual's dream lucidity is correlated with their metacognitive abilities, feelings of bizarreness in the dream imagery (Yu & Shen, 2020), and degree of selfawareness (Kahan, 1994;Yu & Shen, 2020). ...
Article
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Dream lucidity, the awareness of consciousness in dreams, is linked to functions that support reality monitoring in differentiating between internally and externally generated memories. However, lucid dreams have been argued to result from thin reality–fantasy boundaries that lead to reality monitoring errors. To examine the relationship between dream lucidity and reality monitoring, we recruited 31 college students to rate their dream lucidity for 7 days and then complete a reality monitoring test in Experiment 1, observing a positive correlation between dream lucidity and reality monitoring. In Experiment 2, 109 participants rated dream lucidity and the memory characteristics of perceived and imagined events. Dream lucidity was negatively correlated with differences in sensory details between the memories of perceived and imagined events. The findings indicate that individuals with high dream lucidity have a superior ability to discriminate between externally and internally generated events that are susceptible to reality monitoring errors.
... Lucid dreams are heterogeneous in nature and involve various cognitive processes beyond the insight of being in a dream, such as agency and control over the dream plot, episodic memory, or unusual sensorimotor experiences. These lucidity dimensions may vary in occurrence and intensity across and within dreams, and they unfold into conscious experiences stretching along a continuum between nonlucid and lucid dreams (2). Interest in LD dates back thousands of years with likely roots in Eastern meditative practices (e.g., Dream Yoga) (3). ...
... We propose that this reorganization of precision weighting contributes to some LD peculiar features. LD is often highly vivid and includes overwhelming visual, acoustic, and kinesthetic hallucinatory-like experiences with fine-grained details resembling wakeful perception (2). Similarities between LD and wakeful perception were evidenced in a groundbreaking study (14) showing that smooth pursuit eye movements can be elicited in LD and wakefulness, while participants were only capable of producing saccadic eye movements in wakeful imagery. ...
... A stronger focus on prediction errors originating from bodily signals (i.e., higher precision on low-level processing steps) may also elicit active inference and awakening, whereas a shift toward high-level predictions may reestablish non-LD. However, executive functions are partially reinstated in LD, facilitating top-down control over the dream plot, in contrast with non-LD in which these are strongly deactivated (2,9,13,16). Executive functions allow lucid dreamers to flexibly shift attention from one stimulus to another (e.g., from sensory inputs [proprioception, visual, acoustic stimuli … ] to internally generated visual imagery [body image within the dream … ]) or voluntarily recall episodic memories contradicting the unfolding dream scenes. ...
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Lucid dreaming (LD) is a mental state in which we realize not being awake but are dreaming while asleep. It often involves vivid, perceptually intense dream images as well as peculiar kinesthetic sensations, such as flying, levitating, or out-of-body experiences. LD is in the cross-spotlight of cognitive neuroscience and sleep research as a particular case to study consciousness, cognition, and the neural background of dream experiences. Here, we present a multicomponent framework for the study and understanding of neurocognitive mechanisms and phenomenological aspects of LD. We propose that LD is associated with prediction error signals arising during sleep and occurring at higher or lower levels of the processing hierarchy. Prediction errors are resolved by generating a superordinate self-model able to integrate ambiguous stimuli arriving from sensory periphery and higher-order cortical regions. While multisensory integration enables lucidity maintenance and contributes to peculiar kinesthetic experiences, attentional control facilitates multisensory integration by dynamically regulating the balance between the influence of top-down mental models and the precision weighting of bottom-up sensory inputs. Our novel framework aims to link neural correlates of LD with current concepts of sleep and arousal regulation and provide testable predictions on interindividual differences in LD as well as neurocognitive mechanisms inducing lucid dreams.
... For instance, the dreamer might still take some elements of the dream as real like regarding a dream character to be a real person or believing that actions in the dream impact the waking world (Barrett 1992;LaBerge and DeGracia 2000). 3 Third, most LDs don't involve a phenomenal shift like the experience of the dream as unreal and when they do it's quite rare (see Voss et al. 2013). Thus, the need for a phenomenal shift for a dream to be considered lucid might be unnecessaryone might become lucid in a dream without experiencing their dream phenomenally differently. ...
... 7 The problem of disambiguating what should count as "weakly lucid" or "prelucid" (i.e. enabling lucidity) is also found in other characterisations of LD as a state of 'insight' or 'metacognitive insight'(see Baird et al. 2019;Filevich et al. 2015;Voss et al. 2013;Voss & Hobson 2015;Windt & Voss 2018). Some researchers describe LD as "insight into the fact that one is currently dreaming" (Voss & Hobson 2015:5). ...
... Several authors assert that the realisation of the hallucinatory character of the current experience by the dreamer is one of the key features of dream lucidity (Noreika et al. 2010;Revonsuo 2006;Voss & Hobson 2015;Windt & Metzinger 2007). 11 Such a feature seems to be crucial for becoming lucid and is maintained across different degrees of dream lucidity, as found by Voss et al. (2013). From all the above, lucidity, in the technical sense, should be described as the following: ...
Article
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Recently, the construct ‘lucid dreamless sleep’ has been proposed to explain the state of ‘clear light’ described by Tibetan Buddhist traditions, a special state of consciousness during deep sleep in which we’re told to be able to recognise the nature or essence of our mind (Padmasambhava & Gyatrul 2008; Ponlop 2006; Wangyal 1998). To explain the sort of awareness experienced during this state, some authors have appealed to the sort of lucidity acquired during lucid dreaming and suggested a link between both phenomena (Thompson 2014, 2015; Windt 2015a; Windt et al. 2016). Whilst these authors appeal to a non-conceptually mediated form of lucidity, which doesn’t consist of reflective awareness and propositional thought, the question as to whether the state of clear light should be considered a lucid state similar to lucid dreaming still arises. I argue that the concept ‘lucidity’ used to describe this sort of state is imprecise and that two theoretical notions of lucidity should be distinguished. The first one, which I call the technical notion, requires the recognition of the hallucinatory character of my current experience. The second, the broader notion, involves the seeming recognition of being directly acquainted with the phenomenal character of my experience. I spell out these two notions of lucidity and argue that only the latter could apply to the state of clear light sleep.
... After these procedures, additional questionnaires were administered that estimated levels of dream lucidity (Lucidity and Consciousness in Dreams Scale; LuCiD (Voss, Schermelleh-Engel, Windt, Frenzel, & Hobson, 2013)) and kinesthetic sensations in dreams (Kinesthetic Experiences Scale; in-house questionnaire). ...
... Second, not only were flying dreams more likely to be reported by participants who had prior histories of either flying or lucid dreams as in prior studies (Barrett, 1991;Blackmore, 1982), but post-lab flying dreams were characterized by higher levels of control over dream actions than were non-flying dreams. Control over dream events is a second major dimension of lucidity (Voss et al., 2013) and likely accounts for why controlled flying constitutes the most popular lucid dreaming activity planned by trained lucid dreamers (Stumbrys et al., 2014). A sense of control in flying occurs frequently in our set of flying dreams, e.g., '…I could control my propulsion as if I was Superman-incredible…' (P18, Post+9); '… I can control the box with my 2 hands and fly away…' (P17, Post+10); '…I wanted to control my flight, my speed and my direction in the dream…' (P1, Post+10). ...
... In light of the importance of these studies and their accompanying methodological caveats we undertook a study which both optimized conditions for eliciting lucid dreams and applied more appropriate operationalisations and statistics. Specifically: (1) we chose 40 Hz tAC stimulation which previously demonstrated the most robust differences from sham (Voss et al., 2014); (2) we included groups of both naïve and experienced lucid dreamers (ELDs) (Stumbrys et al., 2013); (3) we used morning naps occurring near the REM sleep propensity peak (Webb et al., 1966); (4) we assessed lucid dreaming with real-time signal-verification and validated self-rating scales (Voss, Schermelleh-Engel, Windt, Frenzel, & Hobson, 2013); and (5) we ensured case independence of observations for statistical analyses. Accordingly, we predicted that, compared with sham, 40 Hz stimulation during REM sleep would trigger more signal-verified lucid dreams and higher self-ratings on the Insight and Dissociation Lucidity and Consciousness in Dreams (LuCiD) Scale factors-especially for ELDs, because they are more predisposed to have lucid dreams than are lucid-dreaming naïve participants. ...
... After completing the dream report, participants answered questionnaires about dream lucidity. These included the 8 factors of the LuCiD Scale (Voss et al., 2009(Voss et al., , 2013: insight, control, thought, realism, memory, dissociation, negative emotion and positive emotion, which were assessed by 28 items using 1-5 response scales. ...
... Most prior work on lucid dreaming has focused on its upsides. Lucid dreams are generally more positive than non-lucid dreams [7][8][9][10][11] , potentially as a consequence of the dream control that commonly co-occurs with lucidity 12 . Survey studies consistently reveal that the primary motivation and objective for most lucid dreamers is to have fun 13,14 , for example, choosing to fly or have sex during the dream 15,16 . ...
... Some reported intense positive dream emotions that coincided directly with lucidity (e.g., a "feeling of freedom" upon the realization of dreaming). Together, these low-control lucid dreams suggest that full control over the dream environment is not a necessary precursor to the positive emotions that co-occur with lucidity [7][8][9][10][11] . In at least some cases, positive emotion might arise from observing the vividness of the dream first-hand. ...
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Therapies focused on lucid dreaming could be useful for treating various sleep disorders and other conditions. Still, one major roadblock is the paucity of systematic information on the consequences of attempting these sorts of dreams. The current study sought to quantify positive and negative aspects of seeking lucid dreams, describe their phenomenology in detail, and identify features associated with positive or negative experiences. Observational data from a massive lucid-dream discussion forum were analyzed to capture lucid-dreaming themes. Forum posts were independently rated on multiple dimensions hypothesized to contribute to the valence of lucidity-related phenomena. Our results revealed that lucid dreams can end nightmares and prevent their recurrence, but they can also induce harrowing dysphoric dreams. The realization of dreaming (lucidity) and dreams with high control were both associated with positive experiences. We translated our results into a process model that describes the progression from lucid-dream induction to waking benefit, identifying potential areas of concern. Our results and model suggest that negative outcomes primarily result from failed induction attempts or lucid dreams with low dream control, and that successfully inducing high-control lucid dreams poses low risk for negative outcomes. Lucid dreaming has valuable therapeutic and recreational potential, but a better understanding of the risks is required. Our findings provide new insights into possible negative repercussions and how to avoid them in future applications.
... According to the classic method of Hall and Van de Castle (1966), 50-300 words of each report was required to judge. These were all presented in the online form, which is a valuable source of information that can provide enough privacy for participants to report more real and complete dreams (Voss et al., 2013). ...
... This process engenders an overall reduction of emotionality compared with regular dreams . Indeed, dissociative thought seems to down-regulate negative emotion both in dreaming as during wake Voss et al., 2013), with parallels in lucid dreaming and psychiatric illness [but see ]. ...
... Lucidity and Consciousness in Dreams Scale (LuCiD; Voss, Schermelleh-Engel, Windt, Frenzel & Hobson, 2013). The LuCiD measures key aspects of dream lucidity in detail and consists of 28 statements (e.g. ...
Article
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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.
... Nevertheless, the surrounding literature on this topic is inconsistent. Some researchers state that the majority of laboratory induced lucid dreams are emotionally neutral, rather than positive (Voss et al., 2014;Voss, Schermelleh-Engel, Windt, Frenzel, & Hobson, 2013). However, links between lucidity and positivity in naturalistic sleep environments are arguably of the most significance when seeking to apply lucid dream induction as an intervention in real-life settings. ...
Article
Lucid dreaming is a unique phenomenon with potential applications for therapeutic interventions. Few studies have investigated the effects of lucidity on an individual’s waking mood, which could have valuable implications for improving psychological wellbeing. The current experiment aims to investigate whether the experience of lucidity enhances positive waking mood, and whether lucidity is associated with dream emotional content and subjective sleep quality. 20 participants were asked to complete lucid dream induction techniques along with an online dream diary for one week, which featured a 19-item lucidity questionnaire, and subjective ratings of sleep quality, dream emotional content, and waking mood. Results indicated that higher lucidity was associated with more positive dream content and elevated positive waking mood the next day, although there was no relationship with sleep quality. The results of the research and suggestions for future investigations, such as the need for longitudinal studies of lucidity and mood, are discussed.
... This qualified version of state-dependence of non-spontaneous states still leaves room for asking whether, at least in principle, perception, bodily action, focused attention, metacognitive insight and deliberate control as the putative hallmarks of non-spontaneous states can occur in sleep. There is reason to think we can have perceptual or illusory experiences in sleep and dreams, particularly involving own-body perception [64]; outward behaviour, ranging from small muscle twitches to complex overt behaviours, might be associated with experienced dream actions [64,65]; and lucid dreams show that metacognitive insight and control are compatible with dreaming [51,53,66]. So while it is certainly possible to point to statistical differences between sleep and waking, drawing a sharp line in terms of what it possible in either state seems implausible and likely requires a nuanced account. ...
Article
Whether we are awake or asleep is believed to mark a sharp divide between the types of conscious states we undergo in either behavioural state. Consciousness in sleep is often equated with dreaming and thought to be characteristically different from waking consciousness. Conversely, recent research shows that we spend a substantial amount of our waking lives mind wandering, or lost in spontaneous thoughts. Dreaming has been described as intensified mind wandering, suggesting that there is a continuum of spontaneous experience that reaches from waking into sleep. This challenges how we conceive of the behavioural states of sleep and wakefulness in relation to conscious states. I propose a conceptual framework that distinguishes different subtypes of spontaneous thoughts and experiences independently of their occurrence in sleep or waking. I apply this framework to selected findings from dream and mind-wandering research. I argue that to assess the relationship between spontaneous thoughts and experiences and the behavioural states of sleep and wakefulness, we need to look beyond dreams to consider kinds of sleep-related experience that qualify as dreamless. I conclude that if we consider the entire range of spontaneous thoughts and experiences, there appears to be variation in subtypes both within as well as across behavioural states. Whether we are sleeping or waking does not appear to strongly constrain which subtypes of spontaneous thoughts and experiences we undergo in those states. This challenges the conventional and coarse-grained distinction between sleep and waking and their putative relation to conscious states. This article is part of the theme issue ‘Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation’.
... Nevertheless, the surrounding literature on this topic is inconsistent. Some researchers state that the majority of laboratory induced lucid dreams are emotionally neutral, rather than positive (Voss et al., 2014;Voss, Schermelleh-Engel, Windt, Frenzel, & Hobson, 2013). However, links between lucidity and positivity in naturalistic sleep environments are arguably of the most significance when seeking to apply lucid dream induction as an intervention in real-life settings. ...
Article
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<.001); there were no other significant correlations (all p>.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<.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
... The dreamer's experience is caused by alterations to neural activation and modulation (Hobson and Friston 2012) rather than lesions. A dreamer can display an abrupt shift in cognitive capacity, a good example of this being when a dreamer becomes lucid (Voss et al. 2013). This often leads to greater access to waking memory. ...
Article
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The experience of skilled action occurs in dreams if we take dream reports at face value. However, what these reports indicate requires nuanced analysis. It is uncertain what it means to perform any action in a dream whatsoever. If skilled actions do occur in dreams, this has important implications for both theory of action and theory of dreaming. Here, it is argued that since some dreams generate a convincing, hallucinated world where we have virtual bodies that interact with virtual objects, there is a sense in which we can perform virtual actions. Further, we can also perform skilfully, although not all apparent skilful performance is as it seems. Since the dream world is generated by the dreamer’s own mind, it can be difficult to determine whether the dream world simply allows goals to be achieved without the abilities that would be required in a similar waking scenario. Because of this, individual dream reports alone are insufficient to determine what skills are demonstrated in a particular dream. However, taken with evidence from REM sleep behaviour disorder, incompetent dreams, lucid dreams and motor-skill practise, it is likely that skilled virtual dream performance at times involves both opportunity for virtual behaviour and the display of competence. Evidence from cognitive science suggests that dreamers can also lose competence through forgetting and other cognitive incapacities but, more surprisingly, it is possible to gain abilities in a robust sense, consistent with the idea that some dreams, at least, are virtual realities rather than imagination.
... This process engenders an overall reduction of emotionality compared with regular dreams (Voss et al., 2018). Indeed, dissociative thought seems to down-regulate negative emotion both in dreaming as during wake (LaBerge and Rheingold, 1991;Voss et al., 2013), with parallels in lucid dreaming and psychiatric illness [but see (Mota et al., 2016)]. ...
... Lucid dreaming is characterized by insight and cognitive control which is supported by the activation of brain areas belonging to the FPCN (for a review, see Baird et al., 2019). As a result, lucid dreams are also more positively valenced than non-lucid dreams (Stocks et al., 2020;Voss et al., 2013). ...
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Affective experiences occur across the wake-sleep cycle—from active wakefulness to resting wakefulness (i.e., mind-wandering or daydreaming) to sleep (i.e., dreaming). Yet, we know little about the dynamics of affective experiences across these states. Here, we investigated the within-person fluctuations in the prevalence and valence of affect experienced during mind-wandering and night-time dreaming. We compared the affective ratings of 328 mind-wandering and 529 dream episodes from 32 healthy adults. In a sub-sample, we additionally analysed the affective ratings of 548 waking episodes from 15 participants. Results showed that mind-wandering was more positively valenced than dreaming, and that both mind-wandering and dreaming were more negatively valenced than active wakefulness. We also compared participants’ self-ratings of affect with external ratings of affective experiences described in verbal reports regarding the same episodes. With self-ratings all the episodes were predominated by positive affect. However, the affective valence of verbal reports changed from positively valenced waking reports to affectively balanced mind-wandering reports to negatively valenced dream reports. Together, the findings show that (1) the positivity bias (i.e., more positive than negative affect) characteristic to waking experiences decreases across the wake-sleep continuum, and (2) conclusions regarding the affective nature of subjective experiences depend on whether self-ratings of affect or the verbal reports describing these experiences are analysed. These findings contribute to our understanding of the nature and possible function of affective experiences across different states of consciousness and call for more integration between the fields of emotion research, mind-wandering research, and dream research.
... Unfortunately, most of them are still lacking standardization and validation (e.g., Hauri et al., 1967;Kallmeyer and Chang, 1997;Schredl, 1999, Schredl, 2004. Many questionnaires focus on specific topics such as dream motifs (e.g., Yu, 2012;Malinowski and Horton, 2014), nightmares (e.g., Belicki, 1992), impactful events and traumas (e.g., Orsillo et al., 2007), emotionality (e.g., Rezzonico and Liccione, 2004;Zadra et al., 2006;Yu, 2007), lucid dreaming (e.g., Voss et al., 2013), REM sleep behavior disorders (e.g., Boeve et al., 2011), or assess dreaming in general but in a rather complex manner (e.g., Kallmeyer and Chang, 1997;Aumann et al., 2012). One reason for the lack of validation is that several questionnaires refer to personal constructs or traits which are difficult to evaluate with other instruments (e.g., Hartmann's concept of thick and thin boundaries, Hartmann et al., 1998). ...
Article
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Validated instruments for the analysis of dream contents are still scarce. Therefore, theaim of this study was to validate the Dreamland Questionnaire (DL-Q) by comparingits results to those of the Hall and van de Castle Coding System (HVDC). Twenty-twoparticipants voluntarily filled in a written dream report as well as our DL-Q questionnaire,in total 30 dreams were collected with both measures. Written reports were analyzedwith the HVDC and results of the two instruments were compared using Pearsoncorrelations. Results showed that correlations were high for dominant characters,pleasantness of dream content, and body-related experiences. However, some DL-Q items showed low correlations and others could not be compared directly, as theHVDC did not include the same set of items. The DL-Q showed satisfactory validityand reliability as a measure of dream criteria and may serve as an effective tool fordiagnosis and evaluation and facilitate future clinical and research studies. Nevertheless,some items could not be compared as part of this study and should be validated infuture investigations. (PDF) The Dreamland: Validation of a Structured Dream Diary. Available from: https://www.researchgate.net/publication/346253923_The_Dreamland_Validation_of_a_Structured_Dream_Diary [accessed Dec 18 2020].
... Lucid dreams-dreams in which the dreamer is aware that they are dreaming and often can influence the ongoing dream narrative, for example, by deliberately performing certain actions in the dream-are generally positive and empowering experiences that lead to increases in the mood after awakening (Stocks et al., 2020;. Dream lucidity is associated with more positive emotions in the dream state compared to non-lucidity (Stocks et al., 2020;Voss et al., 2013) and a variety of positive benefits of lucid dreaming has been demonstrated, such as alleviating nightmares (de Macêdo et al., 2019) and insomnia (Ellis et al., 2020), improving motor skills (Schädlich et al., 2017;, fostering creative problem solving (Stumbrys & Daniels, 2010) or contributing to overall wellbeing and personal growth (Doll et al., 2009;Konkoly & Burke, 2019). Yet anything that can heal, might also do harm, and recently certain concerns were raised about possible adverse effects and risks of lucid dreaming on sleep and health (Soffer-Dudek, 2020;Vallat & Ruby, 2019). ...
Article
Lucid dreams—dreams in which the dreamer is aware that they are dreaming—are generally positive and empowering experiences, for which a variety of benefits have been demonstrated, for example, alleviating nightmares and insomnia, improving motor skills, contributing to creativity and personal growth. Recently, however, certain concerns were raised about the possible risks of lucid dreaming on sleep and health. This study aimed to explore three potential domains of adverse effects—sleep quality, dissociation, and mental well-being—as well as to capture any self-observed negative consequences of lucid dreams within an online sample (N = 489) in which the majority of respondents (94%) were lucid dreamers. According to the results, lucid dream frequency was not associated with poorer sleep quality or with greater dissociation but was linked to greater mental well-being. Moreover, most of the lucid dreams were reported to be emotionally positive experiences and the majority of lucid dreamers did not ascribe any negative consequences to lucid dreaming. Thus, at least from the present findings, the experience of lucid dreaming does not seem to exert evident detrimental effects, although a small proportion of lucid dreams (about 10%) were negatively toned. However, to establish causal relationships future longitudinal studies are needed.
... For example, while lucid dreaming, realising that one is dreaming doesn't necessarily make the phenomenology less realistic (Metzinger, 2003;Revonsuo, 1995). In fact, some describe lucid dreams as being more vivid and realistic than non-lucid dreams (LaBerge, 1985;2000), although this may be due to other cognitive attributes such as increased attention and memory (Filevich, Dresler, Brick & Kühn, 2015;Voss, Schermelleh-Engel, Windt, Frenzel & Hobson, 2013). That is not to say that lucidity cannot or never dispels the sense of presence, just that there isn't a necessary or tight connection between the two. ...
Article
The intuitive view that memories are characterized by a feeling of pastness, perceptions by a feeling of presence, while imagination lacks either faces challenges from two sides. Some researchers complain that the “feeling of pastness” is either unclear, irrelevant or isn’t a real feature. Others point out that there are cases of memory without the feeling of pastness, perception without presence, and other cross-cutting cases. Here we argue that the feeling of pastness is indeed a real, useful feature, and although this feeling does not define memory ontologically, it is a characteristic marker which helps us easily categorise a mental state first-personally. We outline several cognitive features that underlie this experience, including the feeling of past accessibility, ergonomic significance, immersion, objectivity and mental strength. Our account is distinctly phenomenal, rather than doxastic, although our web of beliefs may contribute to this experience.
... This includes dorsolateral prefrontal deactivation, an area associated with higher cognitive processes such as rationality and metacognition (Gottesmann, 2006). Impairments in metacognition and other cognitive features in dreaming that relate to psychosis are mostly associated with nonlucid dreaming -dreams in which we do not realise we are dreaming , with lucid dreams being far less likely to include these impairments (Voss et al., 2013). Dreams are often described as hallucinations and involve a subset of the same neural networks as waking hallucinations although dreams are more immersive and isolated from real stimuli (Waters et al., 2016). ...
Article
The conscious experiences we have during sleep have the potential to improve our empathetic response to those who experience delusions and psychosis by supplying a virtual reality simulation of mental illness. Empathy for those with mental illness is lacking and there has been little improvement in the last decades despite efforts made to increase awareness. Our lack of empathy, in this case, may be due to an inability to accurately mentally simulate what it’s like to have a particular cognitive disorder. Dreaming can help mitigate these deficits by placing the dreamer directly into a realistic virtual simulation and thus increase their capacity for empathy. Increasing empathy would go some way towards reducing the stigma and discrimination faced by people in this group. Recent work suggests that virtual reality can increase empathy towards a variety of marginalised groups, however, this technology is limited in its ability to simulate mental illnesses such as delusions. Dreams, however, are at times virtual reality delusion simulators. They can replicate, to a reasonable degree, delusions and psychosis, and through these experiences, we can learn ‘what it’s like’ to have these conditions. It is essential that we recognise these experiences for what they are, attempt to remember and reflect on them. Instead of disregarding dreams due to their unusualness and bizarreness, we can learn from these experiences and expand our understanding of the human condition and its many forms.
... Then comes the first REM episode, with its desynchronized EEG similar to W, and muscle atonia. Several studies (memory of dreams after waking up during REM or SWS; lucid dreaming during REM also suggest that it is during this state that dreaming activity takes place in a privileged way [46,100], although dreams can also take place during SWS [85]. Because of this complex phenomenology, this state usually deviates from the other natural states in the relation between wakefulness and awareness! ...
Thesis
Rapid eye movement (REM) sleep is a sleep state exhibiting low-amplitude, high-frequency cortical activity, similar to wakefulness. However, recent studies have shown that certain cortical areas exhibit slow activity close to that of slow-wave sleep. The objective of the thesis is to better characterize the temporal-spatial distribution of these slow and fast oscillations, and then to propose a computational model to make predictions on the mechanisms responsible for this complex distribution of cortical activity.We first analysed multisite recordings of local field potential and showed that, in somatomotor areas, slow REM activity exhibits several differences from that of slow-wave sleep. In contrast, this activity is not observed in the hippocampus and mPFC.Secondly, we propose a model of the entire mouse cortex in REM, by implementing a hypothesis of heterogeneous neuromodulation within the cortex. This model is composed of a network of mean fields, connected to each other following the connectome of the mouse using The Virtual mouse Brain simulator, and with different levels of adaptation, in accordance with our biological results.Under these conditions, the model reproduces the distribution of slow and fast oscillations in the somatomotor and other cortical areas. Thus, we propose that a dynamic distribution of cholinergic signalling may explain specific features of REM cortical activity with respect to slow-wave sleep and wakefulness.
... Even when restricting the investigation to (adult) humans, this question is not well addressed by the abolition of subjective experience (whether sudden or gradual) induced by DOC, anaesthesia or sleep; and although dreams may theoretically serve this function, they are inherently difficult to induce and study (although research is increasingly tackling this challenge 60,63,64,[122][123][124]. Fortunately, there is a powerful alternative to investigate interventions whereby consciousness is not abolished tout court, but rather radically and systematically perturbed in terms of its subjective aspects, engendering subjective experiences outside the usual range. ...
Thesis
Different perturbations of the brain’s delicate functioning, ranging from transient pharmacological interventions to severe trauma, can result in altered states of consciousness. To illuminate how the neurobiology and organization of the human brain support consciousness, we need to identify changes in brain function that accompany alterations in conscious state. However, the brain is a paradigmatic example of a complex system, raising the question: which aspects of its complex functioning and architecture should be the focus of our investigation? Traditionally, the quest for the “neural correlates of consciousness” has been framed in terms of spatial localisation: which brain regions are most relevant for consciousness? Complementing this extensive body of work, in my thesis I consider three alternative ways of conceptualising brain function (quantified from functional MRI), and how it may support consciousness. First, I adopt a time-resolved perspective, decomposing brain activity into predominantly integrated or segregated patterns of dynamic functional connectivity. Building on my previous work in anaesthesia and disorders of consciousness, I show how the dynamic interplay of functional integration and segregation is reshaped by the classic serotonergic psychedelic, LSD. Second, I consider a frequency-resolved perspective, decomposing functional brain activity into patterns of structure-function coupling across scales: the harmonic modes of the human connectome. This “connectome harmonic decomposition” of brain activity reveals a generalisable neural signature of loss of consciousness, whether due to anaesthesia or brain injury. A mirror-reverse of this harmonic signature characterises the altered state induced by LSD or ketamine. Connectome harmonics provide a robust indicator of consciousness across datasets, correlating with physiological and subjective variables. On the theoretical side, neuroscientific theories postulate that consciousness depends on the integration of information by a “global workspace” of brain regions. However, these accounts treat “information” as a primitive, whereas the recent framework of information decomposition has shown that Shannon information is actually a composite of several more fundamental kinds of information, including synergistic information, which is available only when a set of sources are considered jointly, and redundant information, which is available from multiple individual sources. Demonstrating the importance of disentangling these different kinds of information, I develop a framework for information-resolved analysis of brain activity, based on information decomposition. Combining functional and diffusion MRI, PET, and transcriptomics, I show that higher cognitive systems in the brain leverage the efficiency of synergistic information, whereas redundant interactions are predominantly associated with modular, structurally-coupled sensorimotor systems. Finally, by explicitly taking into account these fundamental kinds of information, I formalise the “global workspace” architecture in information-theoretic terms, revealing that both anaesthesia and disorders of consciousness induce a breakdown of synergistic integration in the brain’s Default Mode Network. Conceptually, these results contribute to reconciling two prominent theories of consciousness, the Global Neuronal Workspace Theory and Integrated Information Theory. Overall, viewing the brain as a time-, frequency-, and information-resolved complex system offers fruitful new ways to understand the brain’s functional architecture, laying the foundations to map the rich landscape of human consciousness.
... Claiming that humans are unaware of a specific type of mental content is a notoriously difficult endeavor. For instance, what was long held as wholly unconscious phenomena, such as dreams or subliminal perception, have been overturned by more sensitive measures which show that degrees of awareness can be detected (Fazekas et al., 2019;Green et al., 1994;Koch et al., 2016;Laberge, 1980;Overgaard et al., 2006;Ramsøy and Overgaard, 2004;Sandberg et al., 2010;Siclari et al., 2017;Voss et al., 2013). ...
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Double-blinding subjects to the experiment's purpose is an important standard in neurofeedback studies. However, it is difficult to provide evidence that humans are entirely unaware of certain information. This study used insights from consciousness studies and neurophenomenology to develop a contingency awareness questionnaire for neurofeedback. We assessed whether participants had an awareness of experimental purposes to manipulate their attention and multisensory perception. A subset of subjects (5 out of 20) gained a degree of awareness of experimental purposes as evidenced by their correct guess about the purposes of the experiment to affect their attention and multisensory perceptions specific to their double-blinded group assignment. The results warrant replication before they are applied to clinical neurofeedback studies, given the considerable time taken to perform the questionnaire (~25 min). We discuss the strengths and limitations of our contingency awareness questionnaire and the growing appeal of the double-blinded standard in clinical neurofeedback studies.
... Additionally, insight, along with 'control' as another component that may be present in lucid dreams and administers dream plots (Voss & Hobson, 2015), can be associated with positive emotions (Stumbrys & Erlacher, 2016;LaBerge & Rheingold, 1990). Evidence suggests that the frequency and intensity of positive emotions in lucid dreams are higher than non-lucid dreams (Voss & Voss, 2014;Voss et al., 2013;Thomas et al., 2015;Gackenbach, 1988). ...
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In the waking state, in the absence of meta-awareness, mind wandering with specific contents can lead to negative mood. Such negative mood can be incorporated into dreaming according to the continuity hypothesis of dreaming. In this paper we argue that in the presence of what we call ‘sustained phenomenal meta-awareness’, negative mood would not follow mind wandering in waking. Sustained phenomenal meta-awareness has a non-sensory, non-affective phenomenal character. It is essentially intransitive, prereflectively self-aware, non-propositional, non-conceptual and devoid of subject-object structure. In other words, this unique kind of meta-awareness is non-representational. Evidence is then provided that such sustained phenomenal meta-awareness can be incorporated into the subsequent dream state as non-dual lucid dreaming in which, again, no negative mood would arise. Based on the latter observation, we have coined the term ‘mindful mind wandering’ and defined it as mind wandering in the presence of sustained phenomenal meta-awareness. We argue that not only does mindful mind wandering not lead to negative mood in waking, but also its incorporation into dreaming, as non-dual lucid dreaming, result in a state that is free of negative affection.
... Lucid Scale ( Voss et al., 2013) was used for the assessment of lucid dreams. The Lucid Scale consists of 27 items and 8 subscales; ...
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The current study was designed to examine the role of nightmares in psychosis proneness in relation to lucid dreaming. In this correlational study, the sample comprised of 220 young Pakistani adults from both genders (124 women and 96 men) age range from 18 to 26 years (M = 21.14, SD = 1.87). The participants were assessed on nightmares, psychosis proneness, and lucid dreaming through the Mannheim Dream Questionnaire, Inventory of Personality Organization, and The Lucidity and Consciousness in Dreams Scale respectively. Pearson correlation analysis demonstrated significant inter-correlation between dream lucidity, nightmare, and psychosis proneness. Path analysis illustrated dream lucidity as a significant mediator in the link between nightmare and psychosis proneness. The results concluded that dream lucidity plays the role of facilitating factor in the development of psychosis proneness. The findings also provide insight into the role of nightmares and lucid dreaming while examining psychosis proneness.
... Lucid dreaming is characterized by insight and cognitive control which is supported by the activation of brain areas belonging to the FPCN (for a review, see Baird, Mota-Rolim, & Dresler, 2019). As a result, lucid dreams are also more positively valenced than non-lucid dreams (Stocks et al., 2020;Voss, Schermelleh-Engel, Windt, Frenzel, & Hobson, 2013). ...
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Affective experiences occur across the wake-sleep cycle-from active wakefulness to resting wakefulness (i.e., mind-wandering) to sleep (i.e., dreaming). Yet, we know little about the dynamics of affect across these states. We compared the affective ratings of waking, mind-wandering, and dream episodes. Results showed that mind-wandering was more positively valenced than dreaming, and that both mind-wandering and dreaming were more negatively valenced than active wakefulness. We also compared participants' self-ratings of affect with external ratings of affect (i.e., analysis of affect in verbal reports). With self-ratings all episodes were predominated by positive affect. However, the affective valence of reports changed from positively valenced waking reports to affectively balanced mind-wandering reports to negatively valenced dream reports. These findings show that (1) the positivity bias characteristic to waking experiences decreases across the wake-sleep continuum, and (2) conclusions regarding affective experiences depend on whether self-ratings or verbal reports describing these experiences are analysed.
... Both need to coexist in order for conscious experience to manifest. Exceptions include the state of lucid dreaming, during which a level of awareness exists in the absence of wakefulness [1], as well as several disorders of consciousness (DOC), in which various defects of awareness exist in the presence of wakefulness [2,3]. Furthermore, the concept of consciousness awareness exist in the presence of wakefulness [2,3]. ...
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Deep, dreamless sleep is considered the only “normal” state under which consciousness is lost. The main reason for the voluntary, external induction of an unconscious state, via general anesthesia, is to silence the brain circuitry of nociception. In this article, I describe the perception of pain as a neural and behavioral correlate of consciousness. I briefly mention the brain areas and parameters that are connected to the presence of consciousness, mainly by virtue of their absence under deep anesthesia, and parallel those to brain areas responsible for the perception of pain. Activity in certain parts of the cortex and thalamus, and the interaction between them, will be the main focus of discussion as they represent a common ground that connects our general conscious state and our ability to sense the environment around us, including the painful stimuli. A plethora of correlative and causal evidence has been described thus far to explain the brain’s involvement in consciousness and nociception. Despite the great advancement in our current knowledge, the manifestation and true nature of the perception of pain, or any conscious experience, are far from being fully understood.
... Despite this definition, dream lucidity is not a purely dichotomous state (i.e., either present or absent; Stumbrys et al., 2012). Dream lucidity involves multiple components, such as the degree of control over one's own actions and over the dream, awareness of the hallucinatory nature of the dream components (e.g., the dream characters, the dreamer's oneiric body), and access to episodic memories from waking life (for dream lucidity scales, see Stumbrys et al., 2013;Voss et al., 2013). ...
Article
This article presents the feeling priming theory (FPT) of dreaming. According to the FPT, dreaming favors the motivation to avoid aversive anticipated events and to approach gratifying anticipated events. It is suggested that one component of anticipated emotions—anticipated feelings—is reproduced in dreams. Upon awakening and during the day, these anticipated feelings would remain activated (primed) in memory. Consequently, anticipated emotions would exert a greater influence on avoidance and approach behaviors, mainly through an increase in the intensity of anticipatory feelings (i.e., feelings of fear or hope/desire). This article comprises five main sections. First, the need for a new theory of the function of dreaming is addressed. Second, key constructs of the theory are described, including the constructs of “emotion” and “feeling.” Third, a brief overview of the theory is presented. Fourth, seven hypotheses that constitute the core of the theory are discussed along with supporting evidence. Fifth, an explanation of nightmares based on the proposed theory is offered. The FPT represents an alternative to theories that attribute an emotion regulation function to dreaming. It offers a new perspective on the relationship between dreaming and waking emotions. In particular, the FPT does not label nightmares as dysfunctional. Instead, nightmares and other dysphoric dreams are hypothesized to result from the same processes as normal dreaming.
... Premièrement, les mouvements oculaires pourraient être plus nombreux en rêve lucide qu'en SP normal et contaminer le signal gamma observé en frontal (LABERGE et al., 1986 ;VOSS et al., 2009). Par ailleurs, dans sa 2ème étude (VOSS et al., 2014), la lucidité n'était pas évaluée objectivement par le signal LRLR mais par quelques sous-critères d'une échelle subjective au réveil (VOSS et al., 2013) dont la pertinence ne fait pas l'unanimité : le critère de 'dissociation' ('se voir de l'extérieur') n'est pas admis comme une caractéristique définissant le rêve lucide par d'autres groupes (DEGRACIA & LABERGE, 2000). De plus, (BAIRD et al., 2019) proposent que si les valeurs absolues de ces critères augmentaient avec la stimulation, elles restaient semblables à celles retrouvées dans des rêves non lucides (calculés lors de la validation de l'échelle) et dans des intervalles bien inférieurs à celles obtenues dans les vrais rêves lucides. ...
Thesis
Les expériences de notre nuit sont souvent décrites comme des îlots d'activité mentale, internement générées dans un océan d'inconscience. En sous-texte de cette vision se cachent deux pré-supposés que le sommeil lent est un modèle d'inconscience et que le traitement sensoriel du monde extérieur en sommeil paradoxal ne peut être qu'inconscient. Dans cette thèse, nous avons voulu tester ces pré-supposés avec une approche empruntant à trois littératures complémentaires : celle de la conscience, celle du sommeil sain et pathologique et celle de la philosophie de l'esprit. Dans une première étude nous avons mis en évidence l'existence de "blackout' de nuit : une absence total de rappel de contenu du couche au lever dans l'hypersomnie Idiopathique. Nous pensons que notre démonstration de l'existence du phénomène de blackout est intéressante car elle permet, par contraste, de mettre en évidence l'existence d'une expérience minimale de la nuit, comme les philosophes l'avaient suggéré. Dans deux autres études nous avons montré la capacité de patients narcoleptiques (lucides ou non) à traiter l'extérieur pendant des siestes en utilisant comme réponses les muscles de leurs visages. Cela suggère qu'un traitement conscient dans le sommeil peut avoir lieu en sommeil paradoxal chez ces patients. L'ensemble de ce travail de thèse invite à penser que l'idée selon laquelle on perd conscience pendant que l'on dort serait à réévaluer. En effet, une réelle perte de conscience dans le sommeil, si elle existe, pourrait être plutôt transitoire et négligeable face à la fabuleuse pluralité des processus qui se déroulent en son sein.
... More broadly, a phenomenologically detailed investigation enabled by incorporating and potentially adapting (elements of) MPI could help empirically address several open research questions in lucid dream research that have been discussed in philosophy of dreaming. For instance, while some definitions assume a sharper distinction between lucid and non-lucid dreams, philosophical considerations (Windt & Metzinger, 2007;Noreika et al., 2010) as well as recent investigations of dream experience (Mallett et al., 2021) suggest that lucidity, rather than presenting an all-or-nothing phenomenon, might be better described on a continuum with non-lucid dreaming, and that it might make sense to distinguish between various degrees and subtypes of lucidity (Voss et al., 2013). ...
Preprint
In this chapter, we present the problem of dream reports in philosophy and empirical research, examine how the variability of methods and measures influences research results, and suggest that research on the phenomenological features of dreaming could benefit from insights from first-person methods in consciousness research. We consider two interview-based methods developed for acquiring detailed phenomenological reports on waking subjective experience - descriptive experience sampling (Hurlburt, 1990, 2011) and micro-phenomenology (Petitmengin, 2006) - discuss their applicability in dream research, and outline some promising research directions. [Manuscript for a chapter in Dreaming and Memory: Philosophical Issues; prior to peer-review.]
... Research findings in the field of cognitive neuroscience and studies on the relation between sleep disorders, dreams, and levels of consciousness in dreaming (Schredl, Bohusch, Kahl, Mader, & Somesan, 2000;Voss, Schermelleh-Engel, Windt, Frenzel, & Hobson, 2013) have contributed to the knowledge of the neuroanatomical substrate and formal aspects of dreaming and its contents, specific interest of clinical psychology. De Gennaro, Marzano, Cipolli, & Ferrara, (2012) provided data supporting the hypothesis that the encoding and recalling neurophysiological mechanisms of the episodic memory are largely shared along with different states of consciousness, shifting from sleep to waking. ...
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For a long time dreamwork in cognitive-behavioural therapy (CBT) was considered useless and as a technique specific to psychodynamic approaches, consequently overlooked in the treatment course. In the last twenty years, thanks to the contribution of neuroscience studies on sleep and dreams, dreams joined the attention and interest of authors belonging to the CBT field. The central feature of dreamwork in CBT is the abandonment of the exploration of latent meaning, which is instead considered in continuity with the waking life. Dreams reflect a patient’s view of self, world, and future, and are subject to the same cognitive biases as the waking state. Consequently, the dreamwork can be used to get information about the patient, overcome impasses in therapy, restructure self and interpersonal schemas, and stimulate reflective functioning. Therefore, guidelines have been defined and models of well-articulated intervention in terms of process and content, replicable and teachable through specific training structured. This paper aims to provide an overview of theories regarding the use of dreams in CBT, from a clinical perspective, from Beck to more recent proposals.
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Study Objectives 1) To replicate the finding that lucid dreams are associated with physiological activation, including heightened REM density, during REM sleep. 2) To critically test whether a previously reported increase in frontolateral 40 Hz power in lucid REM sleep, used to justify the claim that lucid dreaming is a “hybrid state” mixing sleep and wakefulness, is attributable to the saccadic spike potential (SP) artifact as a corollary of heightened REM density. 3) To conduct an exploratory analysis of changes in EEG features during lucid REM sleep. Methods We analyzed 14 signal-verified lucid dreams (SVLDs) and baseline REM sleep segments from the same REM periods from six participants derived from the Stanford SVLD database. Participants marked lucidity onset with standard left-right-left-right-center (LR2c) eye-movement signals in polysomnography recordings. Results Compared to baseline REM sleep, lucid REM sleep had higher REM density (p=0.002). Bayesian analysis supported the null hypothesis of no differences in frontolateral 40 Hz power after removal of the SP artifact (BH=0.18) and ICA correction (BH=0.01). Compared to the entire REM sleep period, lucid REM sleep showed small reductions in low-frequency and beta band spectral power as well as increased signal complexity (all p<0.05), which were within the normal variance of baseline REM sleep. Conclusions Lucid dreams are associated with higher-than-average levels of physiological activation during REM sleep, including measures of both subcortical and cortical activation. Increases in 40 Hz power in periorbital channels reflect saccadic and microsaccadic SPs as a result of higher REM density accompanying heightened activation.
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Luzides Träumen stellt ein besonderes Traumphänomen dar, das Aspekte des Bewusstseins und des Schlafes in ein Erlebnis integriert. Es zeichnet sich vor allem durch das Bewusstsein der träumenden Person aus, dass sie aktuell träumt. Im luziden Traum sind Träumende in der Lage, aktiv in das Traumgeschehen einzugreifen und es zu verändern. Dadurch werden Bereiche wie die wahrgenommene Selbstwirksamkeit und Selbstkontrolle gestärkt. Luzides Träumen hat als Forschungsgegenstand in den letzten Jahren an Aufmerksamkeit gewonnen, insbesondere in der Neuropsychologie. Wenig erforscht wurde bisher jedoch der Einsatz von luziden Träumen als Behandlungsansatz in der Psychotherapie. Luzidtraumtraining (LTT) stellt einen innovativen Behandlungsansatz dar, der viel Potenzial birgt. Insbesondere bei der Behandlung von Albträumen, auch beispielsweise im Rahmen einer Posttraumatischen Belastungsstörung, wurden bereits erste vielversprechende Ergebnisse bezüglich der Wirksamkeit verzeichnet. Trotz vermehrter Hinweise auf den positiven Effekt von luziden Träumen auf die Psyche, steht die Evaluierung von LTT als psychotherapeutische Technik noch am Anfang und weitere Studien sind notwendig, um den Effekt von LTT tiefergehend zu untersuchen.
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Lucid dreams often coincide with having control over dream events in real-time, although the limitations of dream control are not completely understood. The current study probed the ability of lucid dreamers to reinstate waking scene memories while dreaming. After brief exposure to an experimental scene, participants were asked to reinstate the scene while lucid dreaming (i.e., change dream scenery to match real-world scene). Qualitative analysis revealed that successful dream scene reinstatements were overwhelmingly inaccurate with respect to the original experimental scene. Importantly, reinstatement inaccuracies held even when the dreamer was aware of them during the dream, suggesting a dissociation between memory access while dreaming and dream imagery. The ability to change the environment of a dream speaks to the high amount of lucid dream control, yet the inaccuracies speak to a lack of detailed control. Reinstating context during lucid sleep offers an experimental method to investigate sleep, dreams, and memory.
Chapter
Dream research has demonstrated that dream content and memory sources appear similar between REM and NREM sleep, suggesting similar underlying neurocognitive networks. In the late 1970s, dreaming was proposed to be primarily physiologically stimulated and without psychological basis. This view suggested that dreams resulted from complex neurologic stimulations that negated any possible psychological underpinning or prophetic meanings. Moreover, this physiologic model separated the relationship of dream experiences from emotions, implying that dreams are not clinically important, but simply reflect neurochemical processes. However, in recent years, brain imaging has revealed areas of the brain that are activated during different phases of the sleep–wake cycle, providing a model for how structures in the brain are modulated during sleep. During dreaming, the chemical brain activation is similar to that occurring while awake, but this activation is produced without external stimuli and results in the individual having awareness and perception of the content in the dream scenario, suggesting that primary consciousness is activated. Similar processes have been demonstrated in individuals with psychiatric disease. Understanding the neuroanatomical structures and neurobiological processes involved in dreaming may help us to characterize the physiologic role of dreaming in human health and how aberrant dream processes affect mental illness. This article addresses the neurologic and behavioral components associated with dreaming and the significance associated with various psychiatric disorders.
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The human imagination manifests in countless different forms. We imagine the possible and the impossible. How do we do this so effortlessly? Why did the capacity for imagination evolve and manifest with undeniably manifold complexity uniquely in human beings? This handbook reflects on such questions by collecting perspectives on imagination from leading experts. It showcases a rich and detailed analysis on how the imagination is understood across several disciplines of study, including anthropology, archaeology, medicine, neuroscience, psychology, philosophy, and the arts. An integrated theoretical-empirical-applied picture of the field is presented, which stands to inform researchers, students, and practitioners about the issues of relevance across the board when considering the imagination. With each chapter, the nature of human imagination is examined – what it entails, how it evolved, and why it singularly defines us as a species.
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Although the sense of agency is often reduced if not absent in dreams, our agentive dream experiences can at times be similar to or enhanced compared to waking. The sense of agency displayed in dreams is perplexing as we are mostly shut off from real stimulus whilst asleep. Theories of waking sense of agency, in particular, comparator and holistic models, are analysed in order to argue that despite the isolation from the real environment, these models can help account for dream experience. The dreamer might feel an increased sense of control of their dream bodies and a sense that they can directly control elements of the dream world. Such experiences may at times be caused by superstitious or delusional thinking due to altered cognition and changes to the sleeping brain. Here it is argued that some such experiences are akin to specific waking delusions, such as delusions of grandeur, with similar cognitive features. However, other instances of increased sense of agency in dreaming appear to be sui generis and nothing like what we experience when awake. Lucid control dreams, in which the dreamer realises that they are dreaming and that they can control the dream environment, are examples of such an experience although further nuance is required to account for their specific cognitive attributes. Future empirical research should focus on controlled dream reporting conditions in order to clarify the types of experience that occur and determine the relevant cognitive mechanisms that relate to each type.
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To investigate the neural correlates of lucid dreaming. Parallel EEG/fMRI recordings of night sleep. Sleep laboratory and fMRI facilities. Four experienced lucid dreamers. N/A. Out of 4 participants, one subject had 2 episodes of verified lucid REM sleep of sufficient length to be analyzed by fMRI. During lucid dreaming the bilateral precuneus, cuneus, parietal lobules, and prefrontal and occipito-temporal cortices activated strongly as compared with non-lucid REM sleep. In line with recent EEG data, lucid dreaming was associated with a reactivation of areas which are normally deactivated during REM sleep. This pattern of activity can explain the recovery of reflective cognitive capabilities that are the hallmark of lucid dreaming.
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The purpose of this work was to study the relationship of metacognition, absorption, and depersonalization in hallucinating patients. A within-subjects correlational design was employed. We formed four groups from a clinical population (schizophrenic patients with hallucinations, schizophrenic patients with no hallucinations but with delusions, schizophrenic patients recovered from positive symptoms, and patients with a non-psychotic psychiatric disorder) and a non-clinical control group. All participants were given the Metacognitions Questionnaire (MCQ-30, Wells & Cartwright-Hatton, 2004), the Tellegen Absorption Scale (TAS, Tellegen & Atkinson, 1974) and the Cambridge Depersonalization Scale (CDS, Sierra & Berrios, 2000). Schizophrenic subjects with hallucinations scored significantly higher on the depersonalization scale than any other group, and significantly higher on the absorption scale than any group except for the clinical patient controls. Schizophrenic patients with hallucinations also had significantly more dysfunctional metacognitive beliefs than subjects with no psychiatric pathology. It was further found that the metacognition variable correlated positively with the absorption and depersonalization variables, and that these variables in turn correlated positively with each other. Finally, it should be stressed that the variables that best predict hallucination severity are depersonalization and the MCQ-30 subscale `Need to control thoughts'. We discuss the role of metacognitive and dissociative variables in understanding hallucinations and suggest some approaches to their treatment.
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Functional brain imaging has been used in humans to noninvasively investigate the neural mechanisms underlying the generation of sleep stages. On the one hand, REM sleep has been associated with the activation of the pons, thalamus, limbic areas, and temporo-occipital cortices, and the deactivation of prefrontal areas, in line with theories of REM sleep generation and dreaming properties. On the other hand, during non-REM (NREM) sleep, decreases in brain activity have been consistently found in the brainstem, thalamus, and in several cortical areas including the medial prefrontal cortex (MPFC), in agreement with a homeostatic need for brain energy recovery. Benefiting from a better temporal resolution, more recent studies have characterized the brain activations related to phasic events within specific sleep stages. In particular, they have demonstrated that NREM sleep oscillations (spindles and slow waves) are indeed associated with increases in brain activity in specific subcortical and cortical areas involved in the generation or modulation of these waves. These data highlight that, even during NREM sleep, brain activity is increased, yet regionally specific and transient. Besides refining the understanding of sleep mechanisms, functional brain imaging has also advanced the description of the functional properties of sleep. For instance, it has been shown that the sleeping brain is still able to process external information and even detect the pertinence of its content. The relationship between sleep and memory has also been refined using neuroimaging, demonstrating post-learning reactivation during sleep, as well as the reorganization of memory representation on the systems level, sometimes with long-lasting effects on subsequent memory performance. Further imaging studies should focus on clarifying the role of specific sleep patterns for the processing of external stimuli, as well as the consolidation of freshly encoded information during sleep.
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The goal of the study was to seek physiological correlates of lucid dreaming. Lucid dreaming is a dissociated state with aspects of waking and dreaming combined in a way so as to suggest a specific alteration in brain physiology for which we now present preliminary but intriguing evidence. We show that the unusual combination of hallucinatory dream activity and wake-like reflective awareness and agentive control experienced in lucid dreams is paralleled by significant changes in electrophysiology. 19-channel EEG was recorded on up to 5 nights for each participant. Lucid episodes occurred as a result of pre-sleep autosuggestion. Sleep laboratory of the Neurological Clinic, Frankfurt University. Six student volunteers who had been trained to become lucid and to signal lucidity through a pattern of horizontal eye movements. Results show lucid dreaming to have REM-like power in frequency bands delta and theta, and higher-than-REM activity in the gamma band, the between-states-difference peaking around 40 Hz. Power in the 40 Hz band is strongest in the frontal and frontolateral region. Overall coherence levels are similar in waking and lucid dreaming and significantly higher than in REM sleep, throughout the entire frequency spectrum analyzed. Regarding specific frequency bands, waking is characterized by high coherence in alpha, and lucid dreaming by increased delta and theta band coherence. In lucid dreaming, coherence is largest in frontolateral and frontal areas. Our data show that lucid dreaming constitutes a hybrid state of consciousness with definable and measurable differences from waking and from REM sleep, particularly in frontal areas.
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Sleep can be addressed across the entire hierarchy of biological organization. We discuss neuronal-network and regional forebrain activity during sleep, and its consequences for consciousness and cognition. Complex interactions in thalamocortical circuits maintain the electroencephalographic oscillations of non-rapid eye movement (NREM) sleep. Functional neuroimaging affords views of the human brain in both NREM and REM sleep, and has informed new concepts of the neural basis of dreaming during REM sleep -- a state that is characterized by illogic, hallucinosis and emotionality compared with waking. Replay of waking neuronal activity during sleep in the rodent hippocampus and in functional images of human brains indicates possible roles for sleep in neuroplasticity. Different forms and stages of learning and memory might benefit from different stages of sleep and be subserved by different forebrain regions.
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There is a long-standing controversy surrounding the existence of dream experiences during non-rapid eye movement (NREM) sleep. Previous studies have not answered the question whether this "NREM dream" originates from the NREM sleep mechanism because the subject might simply be recalling experiences from the preceding rapid eye movement (REM) sleep. We scheduled 11 healthy men to repeat 20-minute nap trials separated by 40-minute periods of enforced wakefulness across a period of 3 days. At the end of the nap trial, each participant answered questions regarding the formal aspects of his dream experiences during the nap trial, using the structured interviews. We obtained a total of 172 dream reports after naps containing REM sleep (REM naps) and 563 after naps consisting of only NREM sleep (NREM naps). Dream reports from NREM naps were less remarkable in quantity, vividness, and emotion than those from REM naps and were obtained more frequently during the morning hours when the occurrences of REM sleep were highest. These results suggest that the polysomnographic manifestations of REM sleep are not required for dream experiences but that the mechanisms driving REM sleep alter experiences during NREM sleep in the morning. A subcortical activation similar to REM sleep may occur in human NREM sleep during the morning when REM sleep is most likely to occur, resulting in dream experiences during NREM sleep.
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In a review of Stephen LaBerge’s (1985) Lucid Dreaming, David Foulkes (1985) asked a key question: How are lucid and nonlucid dreams different? He pointed out that such a consideration may be the most interesting implication for ordinary dreaming. The issue is, Foulkes notes, what else changes when you change ordinary dreaming by adding a self that intends and reflects. The focus of this chapter is to review research relevant to these concerns. That is, beyond the obvious difference of awareness of dreaming while dreaming, do the psychological contents of lucid and nonlucid dreams differ in other respects?
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Qualitative alterations of the sense of Self (self awareness, self experience) are ubiquitarious in the different psychotic conditions: in early phases of schizophrenic and schizophreniform disorders-which have been called "I am illnesses"- we may observe feelings of extraneity of psychic acts and functions, basic dissociation in an observing and and observed ego with the perception of qualitative new inner experiences (basic symptoms), loss of personal identity, increasing introversion and compensatory hyperreflexivity (psychotic depersonalization states); in acute or chronic full blown psychotic conditions the impairment of reflexivity and insight supports delusional misidentifications of Self or the loss of a true I, which becomes a mere grammatical figure (depersonation states). These disturbances of Self-consciousness have to be differentiated by psychogenic ones, which may be sustained merely by psychogenic dissociative mechanisms (situational and interpersonal use of splitting) but sometimes interlace with process activity supported phenomena. Viewing these clinical disorders from a subjective perspective allows to elicit relevant issues about the construction of the sense of identity (of having an I) which ought to be taken into account in the up to date debate on the philosophy of mind.
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The aim of this study was to compare the representation of self in REM and SWS dreams. Ninety volunteers slept two non-consecutive nights in the sleep laboratory under electropolygraphic control. They were awakened for one report per night. Awakenings were made, in counterbalanced order, from Slow Wave Sleep and Rapid Eye Movements sleep. Dream reports (90 SWS and 90 REM) were scored by independent judges as regards: a) length (according to temporal units); b) representation of self (according to a nominal eight-point scale). Results showed that: a) REM dream reports were significantly longer than SWS dream reports; b) the representation of Self in REM dream reports is quite similar to the waking experience of Self; c) the representation of Self in SWS dream reports presented a wide variety of characteristics (from a thinking agent or passive observer, to a waking-like Self experience); d) the differences between REM and SWS dream reports in representation of Self persisted independently of report length. Results are discussed referring to a cognitive model of dream production.
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[⇓][1] ![Figure][2] This is not a book for the generalist. It is a specialist text on ‘ existential feelings’, written in the tradition of Husserl, Biswanger and Merleau-Ponty. The author’s aim is to ‘offer a phenomenological analysis of existential feeling and show how this can
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This report describes which emotions are judged to be contextualized or pictured by the imagery of a dream, based on a total of 1,401 dreams. The authors have developed and standardized contextualizing images (CI score). They have shown that the CI score is especially high in people who have experienced trauma. This article examines which emotions are judged on a blind basis to be pictured by the dreams. Data was obtained from 730 Ss. The authors find that the first 2 emotions, fear/terror and helplessness/vulnerability, are the most frequent. The authors also report that the CIs characterized by highest intensity scores tend to be those in which the emotion is judged to be fear/terror and helplessness/vulnerability. Positive emotions are fewer and appear to produce less intense images. The authors report that emotions judged to be pictured were relatively weaker and tended towards more positive emotions in a laboratory-style study, compared to home-reported dreams. In addition, the emotions pictured were more positive in a group of artists and professionals compared to groups of students. Overall, it appears that groups of interest are differentiated more clearly by the CI score than by the type of emotion judged to be pictured. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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This article examines the adequacy of the “rules of thumb” conventional cutoff criteria and several new alternatives for various fit indexes used to evaluate model fit in practice. Using a 2‐index presentation strategy, which includes using the maximum likelihood (ML)‐based standardized root mean squared residual (SRMR) and supplementing it with either Tucker‐Lewis Index (TLI), Bollen's (1989) Fit Index (BL89), Relative Noncentrality Index (RNI), Comparative Fit Index (CFI), Gamma Hat, McDonald's Centrality Index (Mc), or root mean squared error of approximation (RMSEA), various combinations of cutoff values from selected ranges of cutoff criteria for the ML‐based SRMR and a given supplemental fit index were used to calculate rejection rates for various types of true‐population and misspecified models; that is, models with misspecified factor covariance(s) and models with misspecified factor loading(s). The results suggest that, for the ML method, a cutoff value close to .95 for TLI, BL89, CFI, RNI, and Gamma Hat; a cutoff value close to .90 for Mc; a cutoff value close to .08 for SRMR; and a cutoff value close to .06 for RMSEA are needed before we can conclude that there is a relatively good fit between the hypothesized model and the observed data. Furthermore, the 2‐index presentation strategy is required to reject reasonable proportions of various types of true‐population and misspecified models. Finally, using the proposed cutoff criteria, the ML‐based TLI, Mc, and RMSEA tend to overreject true‐population models at small sample size and thus are less preferable when sample size is small.
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The current study focused on the distribution of lucid dreams in school children and young adults. The survey was conducted on a large sample of students aged 6-19 years. Questions distinguished between past and current experience with lucid dreams. Results suggest that lucid dreaming is quite pronounced in young children, its incidence rate drops at about age 16 years. Increased lucidity was found in those attending higher level compared with lower level schools. Taking methodological issues into account, we feel confident to propose a link between the natural occurrence of lucid dreaming and brain maturation.
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In this paper, we address the different ways in which dream research can contribute to interdisciplinary consciousness research. As a second global state of consciousness aside from wakefulness, dreaming is an important contrast condition for theories of waking consciousness. However, programmatic suggestions for integrating dreaming into broader theories of consciousness, for instance by regarding dreams as a model system of standard or pathological wake states, have not yielded straightforward results. We review existing proposals for using dreaming as a model system, taking into account concerns about the concept of modeling and the adequacy and practical feasibility of dreaming as a model system. We conclude that existing modeling approaches are premature and rely on controversial background assumptions. Instead, we suggest that contrastive analysis of dreaming and wakefulness presents a more promising strategy for integrating dreaming into a broader research context and solving many of the problems involved in the modeling approach.
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Two aspects of consciousness are first considered: consciousness as awareness (phenomenological meaning) and consciousness as strategic control (functional meaning). As to awareness, three types can be distinguished: first, awareness as the phenomenal experiences of objects and events; second, awareness as meta-awareness, i.e., the awareness of mental life itself; third, awareness as self-awareness, i.e., the awareness of being oneself. While phenomenal experience and self-awareness are usually present during dreaming (even if many modifications are possible), meta-awareness is usually absent (apart from some particular experiences of self-reflectiveness) with the major exception of lucid dreaming. Consciousness as strategic control may also be present in dreams. The functioning of consciousness is then analyzed, following a cognitive model of dream production. In such a model, the dream is supposed to be the product of the interaction of three components: (a) the bottom-up activation of mnemonic elements coming from LTM systems, (b) interpretative and elaborative top-down processes, and (c) monitoring of phenomenal experience. A feedback circulation is activated among the components, where the top-down interpretative organization and the conscious monitoring of the oneiric scene elicitates other mnemonic contents, according to the requirements of the dream plot. This dream productive activity is submitted to unconscious and conscious processes.
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It is now widely accepted that remembering the past and imagining the future rely on a number of shared processes and recruit a similar set of brain regions. However, memory and future thinking place different demands on a range of processes. For instance, although remembering should lead to early associative retrieval of event details, event construction may be slower for future events, for which details from different memories are combined. In order to shed light on the question of how the brain distinguishes between memories and future thoughts, we investigated the differences in the electrophysiological correlates of the vivid elaboration of future and past events. In the slow cortical potentials of 24 healthy human participants, differences during early elaboration were observed at temporo-parietal and parieto-occipital electrode sites, presumably reflecting differential recruitment of sensory and semantic detail retrieval. Additional differences emerged over the right pre-frontal cortex during later elaboration, which could be linked to differential retrieval demands. In conclusion, the time course differences, which presumably reflect the varying recruitment of sub-processes engaged during mental time travel, will help to understand the mechanisms with which the brain separates memories from future thoughts.
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Models of dream analysis either assume a continuum of waking and dreaming or the existence of two dissociated realities. Both approaches rely on different methodology. Whereas continuity models are based on content analysis, discontinuity models use a structural approach. In our study, we applied both methods to test specific hypotheses about continuity or discontinuity. We contrasted dream reports of congenitally deaf-mute and congenitally paraplegic individuals with those of non-handicapped controls. Continuity theory would predict that either the deficit itself or compensatory experiences would surface in the dream narrative. We found that dream form and content of sensorially limited persons was indifferent from those of non-handicapped controls. Surprisingly, perceptual representations, even of modalities not experienced during waking, were quite common in the dream reports of our handicapped subjects. Results are discussed with respect to feedforward mechanisms and protoconsciousness theory of dreaming.
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Dreaming and waking are two brain-mind states, which are characterized by shared and differentiated properties at the levels of brain and consciousness. As part of our effort to capitalize on a comparison of these two states we have applied Edelman's distinction between primary and secondary consciousness, which we link to dreaming and waking respectively. In this paper we examine the implications of this contrastive analysis for theories of mental illness. We conclude that while dreaming is an almost perfect model of organic psychosis, it is less so for schizophrenia and major affective disorder where it must serve a primarily heuristic role helping us to model hallucinations and delusions but not the diseases themselves.
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We review the literature on the neurobiology of rapid eye movement (REM) and non-rapid eye movement (NREM) sleep states and associated dreams. REM is associated with enhanced activation of limbic and amygdalar networks and decreased activation in dorsal prefrontal regions while stage II NREM is associated with greater cortical activation than REM. Not surprisingly, these disparate brain activation patterns tend to be associated with dramatically different dream phenomenologies and dream content. We present two recent studies which content-analyzed hundreds of dream reports from REM and NREM sleep states. These studies demonstrated that dreamer-initiated aggressive social interactions were more characteristic of REM than NREM, and dreamer-initiated friendliness was more characteristic of NREM than REM reports. Both REM and NREM dreams therefore may function to simulate opposing types of social interactions, with the REM state specializing in simulation of aggressive interactions and the NREM state specializing in simulation of friendly interactions. We close our review with a summary of evidence that dream content variables significantly predict daytime mood and social interactions.
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Dreams are descirbed as "single-minded," meaning that they tend to be unaccompanied by other, simultaneous streams of thought and imagery. Four manifestations of single-mindedness are discussed: (1) the absence of a reflective awareness that one is dreaming while the dream is in progress; (2) the absence of alternative images and thoughts while attending to the primary dream content; (3) the tendency for dream content to stay on a single thematic track; (4) the absence of a set to remember the dream while it is in progress. This isolation of dream content, from other thought systems is then considered as but one manifestation of a more generalized relative isolation of dream content, which includes isolation from presleep stimuli, contemporaneous stimuli, organismic state, and autonomic and motor activity. Some of the implications of dream isolation for dream psychophysiology and theories of dreaming are outlined.
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Consciousness has a number of apparently disparate properties, some of which seem to be highly complex and even inaccessible to outside observation. To place these properties within a biological framework requires a theory based on a set of evolutionary and developmental principles. This paper describes such a theory, which aims to provide a unifying account of conscious phenomena.
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Most early studies of consciousness have focused on human subjects. This is understandable, given that humans are capable of reporting accurately the events they experience through language or by way of other kinds of voluntary response. As researchers turn their attention to other animals, "accurate report" methodologies become increasingly difficult to apply. Alternative strategies for amassing evidence for consciousness in non-human species include searching for evolutionary homologies in anatomical substrates and measurement of physiological correlates of conscious states. In addition, creative means must be developed for eliciting behaviors consistent with consciousness. In this paper, we explore whether necessary conditions for consciousness can be established for species as disparate as birds and cephalopods. We conclude that a strong case can be made for avian species and that the case for cephalopods remains open. Nonetheless, a consistent effort should yield new means for interpreting animal behavior.
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This article reviews studies of the neural correlates of dissociative experiences, as assessed by positron emission tomography and functional magnetic resonance imaging, with reference to van der Kolk and colleagues' definitions of primary, secondary, and tertiary dissociation. Key cortical structures involved in these processes include the medial prefrontal, anterior cingulate, somatosensory and insular cortex, and the thalamus. Distinctive neural correlates of primary and secondary dissociative experiences in individuals who have posttraumatic stress disorder are regarded as supporting state-phase models of animal defensive reaction to external threat. Disconnection of neural pathways normally linking self-awareness with body-state perception, occurring as a result of childhood trauma, may occasion the development of tertiary dissociative identities. Suggestions for future research are discussed.