Frequency of lucid dreaming in a representative German sample

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

Consciousness during dreams

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.     

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

In this article, we present results from an interdisciplinary research project aimed at assessing consciousness in dreams. For this purpose, we compared lucid dreams with normal non-lucid dreams from REM sleep. Both lucid and non-lucid dreams are an important contrast condition for theories of waking consciousness, giving valuable insights into the structure of conscious experience and its neural correlates during sleep. However, the precise differences between lucid and non-lucid dreams remain poorly understood. The construction of the Lucidity and Consciousness in Dreams scale (LuCiD) was based on theoretical considerations and empirical observations. Exploratory factor analysis of the data from the first survey identified eight factors that were validated in a second survey using confirmatory factor analysis: INSIGHT, CONTROL, THOUGHT, REALISM, MEMORY, DISSOCIATION, NEGATIVE EMOTION, and POSITIVE EMOTION. While all factors are involved in dream consciousness, realism and negative emotion do not differentiate between lucid and non-lucid dreams, suggesting that lucid insight is separable from both bizarreness in dreams and a change in the subjectively experienced realism of the dream.     

I did not expect to be dreaming: Explaining realization in lucid dreams with a Bayesian framework

The commonsense view is that a lucid dream starts when the dreamer realizes that they are currently dreaming. The notion of realization, however, has been accepted at face value, with little consideration of whether the dreamer realizes that they are dreaming in the sense of actual reasoning, or if it is a mere epiphenomenon of lucid dream initiation. This article offers a solution to this problem by, first, arguing that the transition to lucidity can occur as a result of successful reasoning, and second, building a model of this reasoning in terms of probabilistic reasoning. The established Bayesian model explains realization in lucid dreams taking under consideration two factors: the beliefs that the dreamer holds on what is generally probable and improbable, and the dreamer’s admissibility of being in a dream. Defended against important objections, the model offers an explanation of lucid dream initiation, relevant for future research on dreaming.     

Inducing lucid dreams by olfactory-cued reactivation of reality testing during early-morning sleep: A proof of concept

The reliable induction of lucid dreams is a challenge in lucid dream research. In a previous study by our research group we were able to induce in about 50% of the participants a lucid dream in a single sleep laboratory night by combining a wake-up-back-to-bed sleep protocol and a mnemonic technique. In the present study, we extended our previous procedure by additional presentation of an odor during sleep to reactivate memory traces about reality testing. In total 16 male participants spent a single night in the sleep lab whereas the procedure induced in two participants a lucid dream (12.5%). The induction rate stays below the success rate of our previous study and therefore odor-cueing seems not a promising technique for inducing lucid dreams. Beside the odor presentation, several other methodological changes have been made, which will be discussed and hopefully help further dream engineering to improve induction techniques.     

Attempted induction of signalled lucid dreaming by transcranial alternating current stimulation

Neurophysiological correlates of self-awareness during sleep (‘lucid dreaming’) remain unclear despite their importance for clarifying the neural underpinnings of consciousness. Transcranial direct (tDC) and alternating (tAC) current stimulation during sleep have been shown to increase dream self-awareness, but these studies’ methodological weaknesses prompted us to undertake additional study. tAC stimulation was associated with signal-verified and self-rated lucid dreams—but so was the sham procedure. Situational factors may be crucial to inducing self-awareness during sleep.     

Partial memory reinstatement while (lucid) dreaming to change the dream environment

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.     

Properties of the organization of memory for people: Evidence from dream reports

Steyvers and Tenenbaum (2005) showed that semantic networks for words have three organizational properties: short average path lengths, high clustering, and power law degree distribution. If these are general properties of memory organization, they would apply to memory for other complex material, including people and relations between them. In addition, if during dreaming, characters are generated via knowledge in the dreamer’s memory, the three properties would be found in a relational network of characters in dreams. In dream reports from three individuals, two characters in the same dream were considered affiliated. Resulting social networks have the three properties, with the power law holding when low degrees are omitted. One network with a treelike outline is different from the other two. Results suggest associative memory has the three properties, and demonstrate that dream reports are a potentially valuable source for information about social networks.     

When Dreams Become Reality

In three experiments, we found that after a subtle suggestion, subjects falsely recognized words from their own dreams and thought they had been presented during the waking state. The procedure used in these studies involved three phases. Subjects studied a list of words on Day 1. On Day 2, they received a false suggestion that some words from their previously reported dreams had been presented on the list. On Day 3, they tried to recall only what had occurred on the initial list. Subjects falsely recognized their dream words at a very high rate—sometimes as often as they accurately recognized true words. They reported that they genuinely “remembered” the dream words, as opposed to simply “knowing” that they had been previously presented. These findings, which suggest that dreams can sometimes be mistaken for reality, have significant implications for the practice of psychotherapy.     

Dreaming

The aim is to discover a principle governing the formation of the dream. Now dreaming has an analogy with consciousness in that it is a seeming-consciousness. Meanwhile consciousness exhibits a tripartite structure consisting of (A) understanding oneself to be situated in a world endowed with given properties, (B) the mental processes responsible for the state, and (C) the concrete perceptual encounter of awareness with the world. The dream analogues of these three elements are investigated in the hope of discovering the source of the kinship between dream and consciousness. The dream world (A) proves to be a logically impossible world, limited by nothing more than sheer narratability. The internal world (B) of the dreamer is notable for the limitlessness of the scope allotted to the imagination (exactly taking over the offices of rational function), together with the presence of two important phenomena encountered in waking consciousness: a measure of interiority, and the positing of a world. Finally (C), the dream further replicates consciousness in so far as we seem in dreaming concretely to experience our physical surrounds in the form of perceptual imagining. These properties play their part in enabling the dream to be a seeming-consciousness. At the same time they are such as to necessitate its not being consciousness. It is proposed that in the light of these properties, and those composing the state of consciousness, the dream simply is the imagining of consciousness.     

汉字命名与句子阅读中的同音字密度效应

采用两个实验探讨同音字密度对于汉字识别的影响。实验一采用命名任务,结果发现高同音字密度的汉字的加工时间短于低同音字密度的汉字,说明在汉字识别中,同音字密度起促进作用;实验二运用眼动分析的方法,考察在句子阅读中的同音字密度效应。结果发现,读者对高、低同音字密度汉字的加工在各眼动指标上均没有显著差异,说明在正常句子阅读中,同音字密度的效应消失。     

Lights and lattices and where they are seen

The article discusses characteristics of internal visual images and is based on personal observations of lucid dream and hypnopompic phenomena. In the context of lucid dreaming there sometimes occur persisting bright lights that do not behave like ordinary dream images. These phenomena appear as areas of light, peripheral light, disks of light, sun-like concentrations of light, and fullness of light. These luminous phenomena remain in a fixed location in my view in spite of any dreamed body movement, may appear in different dreams in the same locations, are not truly representational, and appear to be unrelated to other dream images, visual or otherwise. These stable intense lights remain in a fixed location in relation to an area defined by keeping the head still and moving the eyes. This area is the space that is filled at times by scannable hypnopompic geometrical patterns or scannable hypnagogic complex images. Although space-filling patterns look like they extend like a dome over the eyes, a close examination shows that they have a two-dimensional flatness that reaches over the entire scannable area. The observation of these patterns as flat becomes understandable when we think of the internal image as having no distance or separation from the seeing of the image, that is, as being experienced face on at every point. The flatness of the hypnopompic pattern implies the flatness of all internal images. The experiences translates the flat image to external positions around the eyes. This translation is explained.     

Narrative Representation and Phenomenological Knowledge

The purpose of this paper is to demonstrate that narrative representations can provide knowledge in virtue of their narrativity, regardless of their truth value. I set out the question in section 1, distinguishing narrative cognitivism from aesthetic cognitivism and narrative representations from non-narrative representations. Sections 2 and 3 argue that exemplary narratives can provide lucid phenomenological knowledge, which appears to meet both the epistemic and narrativity criteria for the narrative cognitivist thesis. In section 4, I turn to non-narrative representation, focusing on lyric poetry as presenting a disjunctive objection: either lucid phenomenological knowledge can be reduced to identification and fails to meet the epistemic criterion, or lucid phenomenological knowledge is provided in virtue of aesthetic properties and fails to meet the narrativity criterion. I address both of these problems in sections 5 and 6, and I close with a tentative suggestion as to how my argument for narrative cognitivism could be employed as an argument for aesthetic cognitivism.     

The multiplicity of dreams: cognitive-affective correlates of lucid, archetypal, and nightmare dreaming

This preliminary research is the first to compare lucid, nightmare, and archetypal-mythological dreams on dimensions important in previous research on each. A first study of 100 subjects showed all three forms significantly correlated with each other and with estimates of dream recall. In a second study, 41 subjects were selected from the above on the basis of relative specialization in each dream form, with a control group equally high on dream recall. Here, the lucid and archetypal dreamers tended to separate themselves from nightmare sufferers on the basis of high imaginativeness, proclivity to waking mystical experience, spatial/analytic skills, and physical balance. It appears that the intensification of dreaming is expressed positively or negatively, depending on variations in these cognitive dimensions.     

Processing and storage in working memory span

Two experiments are reported that address theoretical assumptions as to the nature of working memory involved in working memory span tasks (Daneman & Carpenter, 1980). Experiment 1 used a version of the sentence span task, and Experiment 2 combined arithmetic verification with recall of presented words. In each experiment, working memory processing span was assessed independently of temporary storage span prior to their combination. Combined task performance under high demand for each component resulted in substantial residual performance for both task elements, particularly in Experiment 2. The results do not challenge the utility of the sentence span task as a measure of on-line cognition, but they raise concerns as to how resource might be allocated to processing and storage elements of the task within a single flexible resource pool, or between different resources of a multiple component working memory system. Although both models lack predictive power regarding resource allocation in these tasks, the multiple resource model appears to offer the better account.     

Induction of lucid dreams: A systematic review of evidence

In lucid dreams the dreamer is aware of dreaming and often able to influence the ongoing dream content. Lucid dreaming is a learnable skill and a variety of techniques is suggested for lucid dreaming induction. This systematic review evaluated the evidence for the effectiveness of induction techniques. A comprehensive literature search was carried out in biomedical databases and specific resources. Thirty-five studies were included in the analysis (11 sleep laboratory and 24 field studies), of which 26 employed cognitive techniques, 11 external stimulation and one drug application. The methodological quality of the included studies was relatively low. None of the induction techniques were verified to induce lucid dreams reliably and consistently, although some of them look promising. On the basis of the reviewed studies, a taxonomy of lucid dream induction methods is presented. Several methodological issues are discussed and further directions for future studies are proposed.     

Short-term memory, working memory, and inhibitory control in children with difficulties in arithmetic problem solving

The relations between short-term memory, working memory, inhibitory control, and arithmetic word problem solution were studied in children who were poor in arithmetic problem solving (n = 23). The children were compared with a group of good problem solvers (n = 26), matched for vocabulary, age, and gender. The results corroborate the hypothesis of poor problem solvers' general deficit in inhibitory processes. They had lower scores and made more intrusion errors in a series of working memory tasks requiring inhibition of irrelevant information. The results showed that problem solving performance is related to the ability of reducing the accessibility of nontarget and irrelevant information in memory. Span tasks that imply passive storage of information showed that poor problem solvers were impaired when they have to retain numerical information, but they did not differ from children who did not have difficulty with mathematics when the material included words.     

Allocation of effort as a function of payoffs for individual tasks in a multitasking environment

SYNWORK1 software allows the examination of how payoffs affect the allocation of effort by people when they perform four different tasks (memory search, arithmetic, visual monitoring, and auditory monitoring). In a previous study (Wang, Proctor, & Pick, 2007), we showed that participants adopted multitasking strategies allocating relative effort appropriate to payoff differences between the arithmetic and memory tasks, but that they exhibited residual effects of prior payoffs when the payoffs were switched. In the present study, we varied the payoff in two different experiments for only one of these tasks, the memory task in Experiment 1 and the arithmetic task in Experiment 2. Doing this allowed consideration of performance for both the task for which payoff changed explicitly and the other cognitive task, for which the payoff difference was implicit (i.e., relative to the explicit payoff that was manipulated). Although participants adjusted performance on the task for which the payoff explicitly varied, the payoff manipulation had less effect than did the explicit payoff manipulations for both tasks used previously. Also, the change in effort on a task resulting from explicitly increasing its payoff was less than that from decreasing the payoff. SYNWORK1 is a good environment for studying multitasking, but has several limitations that need to be addressed to provide a synthetic work environment that allows investigation of a wider range of theoretically relevant issues.     

Emotion and cognition: feeling and character identification in dreaming

This study investigated the relationship between dream emotion and dream character identification. Thirty-five subjects provided 320 dream reports and answers to questions on characters that appeared in their dreams. We found that emotions are almost always evoked by our dream characters and that they are often used as a basis for identifying them. We found that affection and joy were commonly associated with known characters and were used to identify them even when these emotional attributes were inconsistent with those of the waking state. These findings are consistent with the finding that the dorsolateral prefrontal cortex, associated with short-term memory, is less active in the dreaming compared to the wake brain, while the paleocortical and subcortical limbic areas are more active. The findings are also consistent with the suggestion that these limbic areas have minimal input from the dorsolateral prefrontal cortex in the dreaming brain.     

Design as dream and self-representation: Philip Johnson and the Glass House of Atreus

Philip Johnson's masterpiece--the Glass House--is compared to a dream and conceptualized as containing encrypted and embedded representations of the self. Freud's masterpiece--The Interpretation of Dreams--is the theoretical and methodological model for this approach to design-as-dream. Drawing on Johnson's words and forms set in biographical, historical, and cultural context, interpretive paths are traced from manifest design elements of the Glass House to overdetermined latent meanings, yielding new and surprising insights into the Glass House, its elusive architect, and the process of its design. A mirror that reflects an image, a lens that focuses it, and a prism that reveals its components, the Glass House turns a lucid eye onto its maker.