Dream-like mental states can occur during wakefulness.
Nicolas Decat, Arthur Le Coz, Jade Sénéchal, Ilona Scellier-Dekens, Hannah De Verville, Rubén Herzog, François-xavier Lejeune, Isabelle Arnulf, Thomas Andrillon, Delphine Oudiette
Cell Reports April 7, 2026 DOI: 10.1016/j.celrep.2026.117237 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 92 |
| Population | Participants during daytime resting periods |
| Topics | Dreaming |
| Keywords | Cp EEG Clustering Mental experience Sleep-onset period Wake-sleep transition |
| Key findings | Four distinct phenomenological clusters of mental experience emerge across wakefulness, N1 sleep, and N2 sleep, and EEG features differentiate these mental states independently of wake/sleep stages. |
Abstract
A popular view holds that mental experiences uniquely differ between wakefulness and sleep, yet recent work suggests continuity across these stages. Here, we address this question by examining the wake-sleep transition, a window marked by rapid shifts in wake/sleep stages and mental experiences. We recorded electroencephalography (EEG) activity in 92 participants during two daytime resting periods. Participants reported their mental content and scored it along four subjective dimensions (bizarreness, fluidity, spontaneity, and wake perception). Clustering mental experiences (N = 375) based on these scores reveals four clusters with distinct phenomenological profiles. Strikingly, all these mental states emerge across wakefulness, N1 sleep, and N2 sleep. We identify EEG features of spectral power, complexity, and connectivity that differentiate mental states independently of wake/sleep stages. Our findings show that the waking and sleeping brain can produce the same mental state and demonstrate that fine-grained brain dynamics shape the content of mental experiences.
Comparable studies
Other observational and cohort studies on dreaming, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Lucid Dreaming: a State of Consciousness with Features of Both Waking and Non-Lucid Dreaming Student volunteers trained to become lucid and signal lucidity with horizontal eye... | 2009 | Observational study | n = 6 |
| Nightmare Prevalence, Nightmare Distress, and Self-Reported Psychological Disturbance Young adults with a mean age of 20 years | 2002 | Prospective observational study | n = 116 |
| Long-term effects of extreme situational stress on sleep and dreaming Survivors of traumatic events who complained of sleep disturbances, compared with... | 1987 | Case-control study | n = 11 |
| The relationship of nightmare frequency and nightmare distress to well‐being Adults who reported dreams | 2004 | Observational cohort | n = 147 |
| Dreaming in NREM Sleep: A High-Density EEG Study of Slow Waves and Spindles Healthy human subjects | 2018 | Observational cohort | n = 14 |
Citations in the library
Cites 41
- Are There Levels of Consciousness? Trends in Cognitive Sciences April 22, 2016
- Dreaming as mind wandering: evidence from functional neuroimaging and first-person content reports. Frontiers in Human Neuroscience 2013
- Assessing sleep consciousness within subjects using a serial awakening paradigm Frontiers in Psychology 2013
- Real-time dialogue between experimenters and dreamers during REM sleep. Current Biology April 12, 2021
- A new neurocognitive theory of dreams. Dreaming March 1, 2001
and 36 more in the library