Episodic thought distinguishes spontaneous cognition in waking from REM and NREM sleep.
Benjamin Baird, Mariel Kalkach Aparicio, Tariq Alauddin, Brady A. Riedner, Melanie Boly, Giulio Tononi
Consciousness and Cognition 2022 DOI: 10.1016/j.concog.2021.103247 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational study Peer reviewed |
|---|---|
| Sample size | 138 |
| Population | Individuals who underwent experience-sampling during wakefulness and serial awakenings in sleep |
| Topics | Dreaming |
| Keywords | Autonoetic consciousness Episodic future thought Episodic memory Mental time travel Mind-wandering Spontaneous thought |
| Citations | 17 |
| Key findings | Episodic thoughts of the past and future rarely occur in N2 or REM sleep, while waking spontaneous thought shows a strong prospective bias and frequent autobiographical planning. |
Abstract
Evidence suggests continuity between cognition in waking and sleeping states. However, one type of cognition that may differ is episodic thoughts of the past and future. The current study investigated this across waking, NREM sleep and REM sleep. We analyzed thought reports obtained from a large sample of individuals (N = 138) who underwent experience-sampling during wakefulness as well as serial awakenings in sleep. Our data suggest that while episodic thoughts are common during waking spontaneous thought, episodic thoughts of both the past and the future rarely occur in either N2 or REM sleep. Moreover, replicating previous findings, episodic thoughts during wakefulness exhibit a strong prospective bias and frequently involve autobiographical planning. Together, these results suggest that the occurrence of spontaneous episodic thoughts differs substantially across waking and dreaming sleep states. We suggest that this points to a difference in the way that human consciousness is typically experienced across the sleep-wake cycle.
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
Cited by 10
- Topographic-dynamic reorganisation model of dreams (TRoD) - A spatiotemporal approach. Neuroscience & Biobehavioral Reviews May 1, 2023
- Self-caught reports of dreaming and mind wandering in a naturalistic environment: an online questionnaire study Phenomenology and the Cognitive Sciences June 11, 2025
- Cognitive control and semantic thought variability across sleep and wakefulness March 14, 2023
- Memory reactivations during sleep: a neural basis of dream experiences? March 6, 2023
- The kaleidoscope of bizarreness: The analysis of first-person-reports shows the relationship between dreaming and mind wandering to be complex. Consciousness and Cognition 2026
and 5 more in the library
Cites 20
- Experience sampling during fMRI reveals default network and executive system contributions to mind wandering. Proceedings of the National Academy of Sciences May 26, 2009
- Decoupling of the brain's default mode network during deep sleep Proceedings of the National Academy of Sciences June 19, 2009
- Dreaming as mind wandering: evidence from functional neuroimaging and first-person content reports. Frontiers in Human Neuroscience 2013
- The cognitive neuroscience of lucid dreaming Neuroscience & Biobehavioral Reviews March 14, 2019
- Assessing sleep consciousness within subjects using a serial awakening paradigm Frontiers in Psychology 2013
and 15 more in the library