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Sleep Apr 2023
Topics: Dreams; Humans
PubMed: 36656722
DOI: 10.1093/sleep/zsad010 -
Philosophical Transactions of the Royal... Feb 2021Metacognitive 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,...
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 , 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'.
Topics: Dreams; Humans; Virtual Reality
PubMed: 33308070
DOI: 10.1098/rstb.2019.0697 -
Frontiers in Psychology 2020In addition to a large variety of somatic symptoms, fever also affects cognition, sleep, and mood. In an online survey with 164 participants, 100 fever dream reports...
In addition to a large variety of somatic symptoms, fever also affects cognition, sleep, and mood. In an online survey with 164 participants, 100 fever dream reports were submitted. Fever dreams were more bizarre and more negatively toned and included more references to health and temperature perception compared to "normal" most recent dreams - findings that are in line with the continuity hypothesis of dreaming. Future studies should follow up this line of research by conducting diary studies during naturally occurring febrile illnesses and sleep laboratory studies with experimentally induced fever. It would also be very interesting to study the effect of thermal stimulation applied during sleep on dream content. This research helps to understand subjective experiences while sleeping in an extreme condition (elevated body temperature).
PubMed: 32047464
DOI: 10.3389/fpsyg.2020.00053 -
Frontiers in Psychology 2015In this paper we propose an emotion assimilation function of sleep and dreaming. We offer explanations both for the mechanisms by which waking-life memories are... (Review)
Review
In this paper we propose an emotion assimilation function of sleep and dreaming. We offer explanations both for the mechanisms by which waking-life memories are initially selected for processing during sleep, and for the mechanisms by which those memories are subsequently transformed during sleep. We propose that emotions act as a marker for information to be selectively processed during sleep, including consolidation into long term memory structures and integration into pre-existing memory networks; that dreaming reflects these emotion assimilation processes; and that the associations between memory fragments activated during sleep give rise to measureable elements of dream metaphor and hyperassociativity. The latter are a direct reflection, and the phenomenological experience, of emotional memory assimilation processes occurring during sleep. While many theories previously have posited a role for emotion processing and/or emotional memory consolidation during sleep and dreaming, sleep theories often do not take enough account of important dream science data, yet dream research, when conducted systematically and under ideal conditions, can greatly enhance theorizing around the functions of sleep. Similarly, dream theories often fail to consider the implications of sleep-dependent memory research, which can augment our understanding of dream functioning. Here, we offer a synthesized view, taking detailed account of both sleep and dream data and theories. We draw on extensive literature from sleep and dream experiments and theories, including often-overlooked data from dream science which we believe reflects sleep phenomenology, to bring together important ideas and findings from both domains.
PubMed: 26347669
DOI: 10.3389/fpsyg.2015.01132 -
Sleep Mar 2015To evaluate the frequency, determinants and sleep characteristics of lucid dreaming in narcolepsy.
OBJECTIVE
To evaluate the frequency, determinants and sleep characteristics of lucid dreaming in narcolepsy.
SETTINGS
University hospital sleep disorder unit.
DESIGN
Case-control study.
PARTICIPANTS
Consecutive patients with narcolepsy and healthy controls.
METHODS
Participants were interviewed regarding the frequency and determinants of lucid dreaming. Twelve narcolepsy patients and 5 controls who self-identified as frequent lucid dreamers underwent nighttime and daytime sleep monitoring after being given instructions regarding how to give an eye signal when lucid.
RESULTS
Compared to 53 healthy controls, the 53 narcolepsy patients reported more frequent dream recall, nightmares and recurrent dreams. Lucid dreaming was achieved by 77.4% of narcoleptic patients and 49.1% of controls (P < 0.05), with an average of 7.6±11 vs. 0.3±0.8 lucid dreams/ month (P < 0.0001). The frequency of cataplexy, hallucinations, sleep paralysis, dyssomnia, HLA positivity, and the severity of sleepiness were similar in narcolepsy with and without lucid dreaming. Seven of 12 narcoleptic (and 0 non-narcoleptic) lucid dreamers achieved lucid REM sleep across a total of 33 naps, including 14 episodes with eye signal. The delta power in the electrode average, in delta, theta, and alpha powers in C4, and coherences between frontal electrodes were lower in lucid than non-lucid REM sleep in spectral EEG analysis. The duration of REM sleep was longer, the REM sleep onset latency tended to be shorter, and the percentage of atonia tended to be higher in lucid vs. non-lucid REM sleep; the arousal index and REM density and amplitude were unchanged.
CONCLUSION
Narcolepsy is a novel, easy model for studying lucid dreaming.
Topics: Adolescent; Adult; Arousal; Case-Control Studies; Cataplexy; Dreams; Dyssomnias; Female; Hallucinations; Humans; Interviews as Topic; Male; Mental Recall; Narcolepsy; Self Report; Sleep Paralysis; Sleep Stages; Sleep, REM; Young Adult
PubMed: 25348131
DOI: 10.5665/sleep.4516 -
Frontiers in Human Neuroscience 2023Dreams are still an enigma of human cognition, studied extensively in psychoanalysis and neuroscience. According to the Freudian dream theory and Solms' modifications of... (Review)
Review
Dreams are still an enigma of human cognition, studied extensively in psychoanalysis and neuroscience. According to the Freudian dream theory and Solms' modifications of the unconscious derived from it, the fundamental task of meeting our emotional needs is guided by the principle of homeostasis. Our innate value system generates conscious feelings of pleasure and unpleasure, resulting in the behavior of approaching or withdrawing from the world of objects. Based on these experiences, a hierarchical generative model of predictions () about the world is constantly created and modified, with the aim to optimize the meeting of our needs by reducing prediction error, as described in the model of cognition. Growing evidence from neuroimaging supports this theory. The same hierarchical functioning of the brain is in place during sleep and dreaming, with some important modifications like a lack of sensual and motor perception and action. Another characteristic of dreaming is the predominance of , an associative, non-rational cognitive style, which can be found in similar altered states of consciousness like the effect of psychedelics. Mental events that do not successfully fulfill an emotional need will cause a prediction error, leading to conscious attention and adaptation of the priors that incorrectly predicted the event. However, this is not the case for (RPs), which are defined by the inability to become reconsolidated or removed, despite ongoing error signal production. We hypothesize that Solms' RPs correspond with the , as described by Moser in his dream formation theory. Thus, in dreams and dream-like states, these unconscious RPs might become accessible in symbolic and non-declarative forms that the subject is able to and make sense of. Finally, we present the similarities between dreaming and the psychedelic state. Insights from psychedelic research could be used to inform dream research and related therapeutic interventions, and vice versa. We propose further empirical research questions and methods and finally present our ongoing trial "Biological Functions of Dreaming" to test the hypothesis that dreaming predicts intact sleep architecture and memory consolidation, a lesion model with stroke patients who lost the ability to dream.
PubMed: 36875230
DOI: 10.3389/fnhum.2023.1080177 -
Frontiers in Psychology 2023Cultural differences in self-construal, human relationships, and values between Western and East Asian people have been suggested. The aim of this article is to...
Cultural differences in self-construal, human relationships, and values between Western and East Asian people have been suggested. The aim of this article is to investigate cultural difference in dreamers' self-construal based on their dreams. We examined the dreams sampled via online questionnaires from 300 non-clinical participants from America and Japan, respectively. The free response for the contents of "impressive dreams in childhood" "recent impressive dreams" was categorized into the five general dream structural patterns. Besides, the participants were asked to answer the scales to investigate participants' cultural self-construal. The current results revealed the prevalence of the independent view of self in American participants and the interdependent view of self in Japanese participants. In addition, we found significant cultural differences in the dream length and structural patterns. For American dreams, the dream-ego had a clear will and strong mobility, and there were obvious ends of dream events. Conversely, for Japanese dreams, the weak agency and vague conscious of the dream-ego were shown, and others could play a main role in one's dreams. These results suggested that each characteristic of the American and Japanese samples may be influenced by the differences in self-construal or in the process of self-formation between American and Japanese cultures.
PubMed: 36874798
DOI: 10.3389/fpsyg.2023.1069406 -
PloS One 2022Memories of the past help us adaptively respond to similar situations in the future. Originally described by Schacter & Addis in 2007, the "constructive episodic...
Memories of the past help us adaptively respond to similar situations in the future. Originally described by Schacter & Addis in 2007, the "constructive episodic simulation" hypothesis proposes that waking thought combines fragments of various past episodes into imagined simulations of events that may occur in the future. This same framework may be useful for understanding the function of dreaming. N = 48 college students were asked to identify waking life sources for a total of N = 469 dreams. Participants frequently traced dreams to at least one past or future episodic source (53.5% and 25.7% of dreams, respectively). Individual dreams were very often traced to multiple waking sources (43.9% of all dreams with content), with fragments of past memory incorporated into scenarios that anticipated future events. Waking-life dream sources are described in terms of their phenomenology and distribution across time and sleep stage, providing new evidence that dreams not only reflect the past, but also utilize memory in simulating potential futures.
Topics: Computer Simulation; Dreams; Humans; Sleep Stages
PubMed: 35316266
DOI: 10.1371/journal.pone.0264574 -
Consciousness and Cognition Aug 2020Information processing during sleep is active, ongoing and accessible to engineering. Protocols such as targeted memory reactivation use sensory stimuli during sleep to...
Information processing during sleep is active, ongoing and accessible to engineering. Protocols such as targeted memory reactivation use sensory stimuli during sleep to reactivate memories and demonstrate subsequent, specific enhancement of their consolidation. These protocols rely on physiological, as opposed to phenomenological, evidence of their reactivation. While dream content can predict post-sleep memory enhancement, dreaming itself remains a black box. Here, we present a novel protocol using a new wearable electronic device, Dormio, to automatically generate serial auditory dream incubations at sleep onset, wherein targeted information is repeatedly presented during the hypnagogic period, enabling direct incorporation of this information into dream content, a process we call targeted dream incubation (TDI). Along with validation data, we discuss how Dormio and TDI protocols can serve as tools for controlled experimentation on dream content, shedding light on the role of dreams in the overnight transformation of experiences into memories.
Topics: Adult; Creativity; Dreams; Equipment Design; Female; Humans; Male; Memory Consolidation; Sleep Stages; Wearable Electronic Devices; Young Adult
PubMed: 32480292
DOI: 10.1016/j.concog.2020.102938 -
Frontiers in Neurology 2020Oneiric Stupor (OS) in Agrypnia Excitata represents a peculiar condition characterized by the recurrence of stereotyped gestures such as mimicking daily-life activities... (Review)
Review
Oneiric Stupor (OS) in Agrypnia Excitata represents a peculiar condition characterized by the recurrence of stereotyped gestures such as mimicking daily-life activities associated with the reporting of a dream mentation consisting in a single oneiric scene. It arises in the context of a completely disorganized sleep structure lacking any physiological cyclic organization, thus, going beyond the concept of abnormal dream. However, a proper differential diagnosis of OS, in the complex world of the "disorders of dreaming" can become quite challenging. The aim of this review is to provide useful clinical and videopolygraphic data on OS to differentiate it from other dreaming disorders. Each entity will be clinically evaluated among the areas of dream mentation and abnormal sleep behaviors and its polygraphic features will be analyzed and distinguished from OS.
PubMed: 33281702
DOI: 10.3389/fneur.2020.565694