Current biology : CB
April 12, 2021
Karen R Konkoly, Kristoffer Appel, Emma Chabani et al.
126 citations
People who are asleep and having a lucid dream—aware that they are dreaming—can perceive questions from an experimenter and answer them in real time using eye movements and facial muscle contractions. In a study of 36 individuals during REM sleep, including frequent lucid dreamers, a novice, and a patient with narcolepsy, participants performed perceptual analysis of new information, held information in working memory, computed simple answers, and gave volitional replies. Correct answers occurred on 29 occasions across 6 individuals, documented by four independent laboratories. This two-way communication channel allows real-time interrogation of dream cognition and characteristics.
Sleep
February 27, 2015
Pauline Dodet, Mario Chávez, Smaranda Leu-Semenescu et al.
115 citations
People with narcolepsy are far more likely to experience lucid dreaming—being aware that they are dreaming while still asleep—than healthy individuals. In a case-control study, 77.4% of 53 narcolepsy patients reported having lucid dreams, compared to 49.1% of 53 controls, averaging 7.6 lucid dreams per month versus 0.3. During monitored naps, 7 of 12 narcoleptic frequent lucid dreamers (but none of 5 controls) successfully signaled from a lucid REM sleep state. Brain wave analysis showed lower delta, theta, and alpha power and reduced frontal coherence during lucid versus non-lucid REM sleep, along with longer REM duration. The findings suggest narcolepsy provides a useful model for studying lucid dreaming.
Brain : a journal of neurology
July 1, 2019
Célia Lacaux, Charlotte Izabelle, Giulio Santantonio et al.
47 citations
People with narcolepsy, who enter REM sleep abnormally quickly and often experience lucid dreaming, show higher creativity than healthy controls. In a study of 185 narcolepsy patients and 126 controls, those with narcolepsy scored higher on the Test of Creative Profile (58.9 vs. 55.1) and the Creativity Achievement Questionnaire (10.4 vs. 6.4). Objective tests of creative performance in 30 patients and 30 controls also favored the narcolepsy group (4.3 vs. 3.7). Most narcolepsy symptoms—sleepiness, hypnagogic hallucinations, sleep paralysis, lucid dreaming, and REM sleep behavior disorder—were linked to higher creativity scores, suggesting that lifelong heightened REM sleep access may enhance creative potential.
Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine
April 1, 2021
Greta Mainieri, Jean-Baptiste Maranci, Pierre Champetier et al.
40 citations
Sleep paralysis and false awakenings are intermediate states between REM sleep and wakefulness. In a sleep-laboratory study of five participants, polysomnography recordings captured five sleep-paralysis episodes and two false awakenings. During sleep paralysis, 70.8% of 3-second mini-epochs showed theta brain waves (compared to 89.7% in normal REM sleep and 21.2% in wakefulness), 93.8% had chin-muscle atonia (vs 89.7% in REM and 33.3% in wakefulness), and 6.9% contained rapid eye movements (vs 11.9% in REM and 8.1% in wakefulness). The electroencephalography spectrum during sleep paralysis was intermediate between wakefulness and REM sleep for alpha, theta, and delta frequencies, while beta frequencies matched normal REM sleep.
May 16, 2023
William Wong, Kátia C. Andrade, Thomas Andrillon et al.
21 citations
preprint
A new open-access database, DREAM, combines sleep magneto/electroencephalography (M/EEG) recordings with standardized dream reports to enable large-scale neurocognitive research on dreaming. The initial release includes 20 datasets from 561 participants and 2649 awakenings, each with at least 20 seconds of high-frequency M/EEG data and a classification of the subject's experience. Analyses demonstrate that features extracted from EEG can predict whether a person reports having had a conscious experience during both REM and NREM sleep. The database aims to overcome the limitations of small sample sizes and methodological variability in dream research, allowing new questions to be addressed at a scale unattainable by individual labs.
Neuroscience & Biobehavioral Reviews
October 16, 2024
Anna Castelnovo, Francesca Siclari, Sara Spaggiari et al.
12 citations
Disorders of Arousal (DOA), traditionally considered unconscious states, may involve conscious experiences more often than previously thought. A narrative review of the literature finds that about 50-60% of adults recall conscious experiences immediately after a DOA episode, while children have a lower recall rate (under 30% when interviewed retrospectively). Patient reports range from brief scenic fragments to elaborate scenarios with plot development, often involving negative emotions and misfortunes, and there is considerable correspondence between subjective experiences and observed behaviors. In many cases, patients appear to enact their dreams, entering a hallucinatory state where internally generated images overlay external percepts. The review discusses implications for clinical management, research, and legal considerations regarding nocturnal violence.
Nature Communications
August 13, 2025
William Wong, Rubén Herzog, Kátia Cristine Andrade et al.
10 citations
A new open database, the DREAM database, combines standardized sleep magneto/electroencephalography (M/EEG) recordings with dream reports from 505 participants across 20 datasets, totaling 2,643 awakenings. Each awakening includes at least 20 seconds of high-resolution sleep EEG (≥100 Hz, ≥2 electrodes) and a classification of the sleeper's reported experience. Analyses showed that reports of conscious experiences during sleep can be predicted from objective EEG features in both REM and NREM sleep. The database aims to overcome limitations of small sample sizes and methodological variability in dream research, enabling larger-scale investigations of the neurocognitive basis of dreaming.
Sleep
February 10, 2025
Yannis Idir, Régis Lopez, Amélie Barbier et al.
5 citations
Disorders of arousal (DoA) episodes, such as sleepwalking, are not a uniform state but involve varying levels of consciousness and responsiveness. In a retrospective questionnaire, 81% of 61 adult patients reported occasional conversations during episodes. Auditory stimulation during N3 sleep triggered episodes in only 7 of 157 trials, and only one patient indirectly responded to verbal prompts. Analysis of 364 home video-recorded episodes from 19 patients found 37 instances of discussion with a bed partner. Patients' ongoing mental content influenced their responses and perception of the outside world. These findings highlight limitations in current diagnostic criteria for DoA.
Journal of Cognitive Neuroscience
September 30, 2025
Karen R Konkoly, Saba Al-Youssef, Christopher Y Mazurek et al.
3 citations
Alpha oscillations, a hallmark of waking visual perception when eyes close, do not reliably increase during lucid dreams when dreamers signal that their dream-eyes are closed. In 150 signals from 11 lucid dreamers, dream-eye closure was associated with fading visual content only about half the time. In three participants where visual content presence versus absence could be compared, increased alpha power accompanied momentary lack of visual content. Real-time reporting via sniffing patterns enables dynamic investigation of dream perception.
bioRxiv (Cold Spring Harbor Laboratory)
September 1, 2025
Jean-Baptiste Maranci, Pierre Champetier, Delphine Oudiette et al.
preprint
Dreams during REM sleep are emotionally fluid and fast-changing, with positive and negative emotions alternating frequently. In a study of 24 lucid dreamers with narcolepsy who reported emotional valence in real-time using facial codes during daytime naps monitored with polysomnography, 62 of 126 naps contained at least one emotional code during REM sleep, yielding 191 codes total. Positive and negative codes were evenly balanced per nap, and over half of naps with at least two codes showed opposite valences. The average duration of a given emotional valence was about one minute, with positive emotions emerging earlier than negative ones. These findings suggest that the emotional dynamics of REM sleep dreams may contribute to understanding how dreams help regulate emotions.
Cell Reports
April 7, 2026
Nicolas Decat, Arthur Le Coz, Jade Sénéchal et al.
Mental experiences during wakefulness and sleep are not as distinct as commonly thought. Analyzing electroencephalography (EEG) from 92 participants during daytime rest, researchers collected 375 reports of mental content scored on bizarreness, fluidity, spontaneity, and wake perception. Clustering these reports revealed four distinct types of mental states. Crucially, all four types occurred across wakefulness, N1 sleep, and N2 sleep. EEG measures of spectral power, complexity, and connectivity differentiated these mental states independently of whether participants were awake or asleep. The findings indicate that the waking and sleeping brain can produce the same mental state, and that fine-grained brain dynamics shape the content of mental experiences.
PLoS Computational Biology
February 1, 2026
Tao Xia, Chuan-Peng Hu, Başak Türker et al.
Sleep is often seen as a state of mental disconnection, but new research shows that decision-making abilities can persist during certain sleep stages. Using facial muscle measurements and computational modeling, the study found that people could make lexical decisions (distinguishing real words from pseudowords) during N1 sleep and lucid REM sleep, though through different brain processes. During N1 sleep, both enhanced sensory-motor processing and increased evidence accumulation supported decisions about words, while pseudowords were selectively impaired, suggesting cognitive resources prioritize meaningful stimuli. In lucid REM sleep, decisions relied solely on evidence accumulation, and participants raised their decision thresholds, requiring more evidence before responding to maintain accuracy despite reduced efficiency. Sleep involves dynamic, state-specific reconfiguration of decision-making mechanisms rather than passive cognitive decline.
Journal of Sleep Research
October 1, 2025
Claudia Picard-Deland, Matteo Cesari, Ambra Stefani et al.
Parasomnias, including disorders of arousal and REM sleep behavior disorder, are increasingly diagnosed using home devices such as actigraphy, EEG headbands, and 2D infrared or 3D time-of-flight cameras with automatic analysis. Traditional video-polysomnographic criteria are becoming more accurate, and deep learning methods classify abnormal polysomnographic signals. Big data from clinical, cognitive, brain imaging, DNA, and polysomnography collections reveal factors associated with parasomnias and, for RBD, may predict individual risk of conversion to overt neurodegenerative disease. Dream engineering, targeted memory reactivation, image repetition therapy, and lucid dreaming help alleviate nightmares. RBD has united movement disorder and sleep neurologists; research into nightmares and sleep-wake dissociations has brought together sleep and consciousness scientists.
Consciousness and Cognition
May 1, 2020
Emma Chabani, Marie Charlotte Vionnet, Romy Beauté et al.
Patients with idiopathic hypersomnia more often report a night blackout—an absence of experiences or recall from sleep onset to offset—than patients with narcolepsy or healthy controls. In a questionnaire study of 133 idiopathic hypersomnia patients, 108 narcolepsy patients, and 128 controls, those with idiopathic hypersomnia and frequent night amnesia had lower dream recall, felt sleep as deeper and mind as blank, and showed a higher proportion of slow wave sleep on retrospectively collected recordings. The night blackout offers a model for studying loss of consciousness during sleep, experienced as contentless, selfless, and timeless upon awakening.
Scientific Reports
February 8, 2018
Delphine Oudiette, Pauline Dodet, Nahema Ledard et al.
Breathing is irregular during REM sleep but stable during non-REM sleep; the reason has been unknown. This study tested whether irregular breathing during REM sleep originates in the cortex and reflects dream content. Twenty-one patients with narcolepsy, who can lucid dream and signal awareness with eye movements, were monitored during naps. Participants were instructed to modify their dream to involve vocalizations or apnea. Most (86%) signaled lucidity in at least one nap. In 50% of lucid naps, dream reports (e.g., diving underwater) matched observed respiratory behavior (e.g., central apnea), sometimes with a preparatory breath. The findings suggest that cortical-subcortical networks controlling voluntary breathing remain active during REM sleep and that breathing irregularities reflect dream content.
Sleep Medicine Reviews
August 1, 2016
Elena Antelmi, Raffaele Ferri, Alex Iranzo et al.
State dissociation disorders occur when features of one state of being—wakefulness, REM sleep, or NREM sleep—intrude into another. Examples include cataplexy, sleep paralysis, REM sleep behavior disorder, and disorders of arousal. The most extreme form, status dissociatus, involves a breakdown of all recognizable states; it can occur intermittently in conditions like narcolepsy type 1 or continuously in agrypnia excitata. This review classifies the full range of diseases and disorders associated with state dissociation and status dissociatus.
Journal of Sleep Research
December 1, 2015
Bastien Herlin, Smaranda Leu-Semenescu, Charlotte Chaumereuil et al.
People who report never dreaming actually do produce dreams but fail to recall them. Among 289 patients with rapid eye movement sleep behaviour disorder (RBD), a condition where people act out their dreams, eight (2.8%) reported no dream recall for at least 10 years, including four who had never recalled a dream in their lifetime. Despite this, all eight non-recallers exhibited daily or near-nightly complex, scenic, dreamlike behaviours and speeches during REM sleep, such as arguing, fighting, and speaking, both by report and on video-polysomnography. They did not recall dreams even after sudden awakenings from REM sleep. These non-recallers did not differ cognitively, clinically, or in sleep measures from matched dream-recallers with RBD. The findings provide strong evidence that non-recallers produce dreams but do not recall them.
Consciousness and Cognition
September 1, 2012
Delphine Oudiette, Marie-José Dealberto, Ginevra Uguccioni et al.
Suppressing REM sleep with the antidepressant clomipramine (50 mg) in 11 healthy young men did not substantially affect dream recall, including report length, complexity, bizarreness, pleasantness, or self-perception of dream or thought-like mentation. REM sleep was suppressed by a marked 81% (range 39-98%). The persistence of long, complex, and bizarre dreams even after partial or total REM suppression suggests that the generation of mental activity during sleep is independent of sleep stage.
Brain : a journal of neurology
June 1, 2010
Laurène Leclair-Visonneau, Delphine Oudiette, Bertrand Gaymard et al.
During REM sleep, rapid eye movements often align with the direction of dream-enacting behaviors in patients with REM sleep behavior disorder, supporting the idea that eyes scan dream scenes. In 56 patients and 17 controls, behaviors occurred 2.1 times more frequently during REM sleep with rapid eye movements than without. When goal-oriented actions like grabbing or climbing occurred, 82% of accompanying rapid eye movements were directed toward the action, rising to 90% for determinant movements. However, 38-42% of behaviors lacked rapid eye movements. The similarity of eye movements between patients and controls suggests this scanning also occurs in normal REM sleep.