Dreams reflect nocturnal cognitive processes: Early-night dreams are more continuous with waking life, and late-night dreams are more emotional and hyperassociative.
Josie E Malinowski, Caroline L. Horton
Consciousness and Cognition February 1, 2021 DOI: 10.1016/j.concog.2020.103071 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational study Peer reviewed |
|---|---|
| Sample size | 68 |
| Population | Participants awoken from sleep in early and late night |
| Topics | Dreaming |
| Keywords | Hyperassociativity Metaphor The continuity hypothesis |
| Key findings | Early-night dreams are more clearly relatable to waking life, while late-night dreams are more emotional-important, time orientation varied, and hyperassociative. |
Abstract
Contributions of specific sleep stages to cognitive processes are increasingly understood. Non-REM sleep is particularly implicated in episodic memory consolidation, whilst REM sleep preferentially consolidates and regulates emotional information, and gives rise to creativity and insight. Dream content reflects these processes: non-REM dreams are more likely to picture episodic memories, whereas REM dreams are more emotional and bizarre. However, across-the-night differences in the memory sources of dream content, as opposed to sleep stage differences, are less well understood. In the present study, 68 participants were awoken from sleep in the early and late night and recorded their dreams and waking-life activities. Early-night dreams were more clearly relatable to (or continuous with) waking life than late-night dreams. Late-night dreams were more emotional-important, more time orientation varied, and more hyperassociative, than early-night dreams. These dream content differences may underlie the mental content that accompanies sleep processes like memory consolidation, emotion-processing, and creativity.
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 20
- Dreaming of the sleep lab PLoS One October 6, 2021
- Do animals dream? Consciousness and Cognition October 1, 2021
- Constructive episodic simulation in dreams PLoS One March 22, 2022
- Enhancing and advancing the understanding and study of dreaming and memory consolidation: Reflections, challenges, theoretical clarity, and methodological considerations Consciousness and Cognition June 27, 2024
- The dynamics of emotional behaviors in rapid eye movement sleep Sleep November 29, 2022
and 15 more in the library
Cites 16
- Metaphor and hyperassociativity: the imagination mechanisms behind emotion assimilation in sleep and dreaming Frontiers in Psychology August 18, 2015
- How You Measure Is What You Get: Differences in Self- and External Ratings of Emotional Experiences in Home Dreams The American Journal of Psychology August 21, 2017
- Waves of the Unconscious: The Neurophysiology ofDreamlikePhenomena and Its Implications for the Psychodynamic Model of the Mind Neuropsychoanalysis 2007
- Dreaming of a learning task is associated with enhanced memory consolidation: Replication in an overnight sleep study. Journal of Sleep Research February 1, 2019
- Daydreams and nap dreams: Content comparisons. Consciousness and Cognition July 9, 2015
and 11 more in the library