Measuring a dreaming population: multilevel temporal organization in 75,000 dream reports
September 24, 2026 preprint DOI: 10.31234/osf.io/tg29q_v1 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational corpus analysis |
|---|---|
| Sample size | 5,524 |
| Population | Dream reports from Dreamseer users, DreamBank, Reddit r/Dreams, and the Sleep and Dream Database, plus matched waking accounts, fiction, and encyclopedic prose |
| Topics | Dreaming |
| Key findings | Emotional valence declined from beginning to end within dream reports, a sequence-dependent effect that survived controls and contributor-level inference. Dreamseer and DreamBank reports declined more steeply than matched waking narratives, fiction, and encyclopedic prose, with roughly two- to five-fold greater descent on the endpoint estimand. The hypothesized failure of emotional resolution at the ending was unsupported; the difference was concentrated earlier, with dreams beginning near neutral and then declining. |
Abstract
Dream reports exhibit reproducible organization at multiple scales. We analyzed >75,000 reports from four platforms: 30,241 reports by 5,524 Dreamseer users and ~45,000 from DreamBank, Reddit r/Dreams, and the Sleep and Dream Database. Within reports, emotional valence declined from beginning to end. Forward and reversed trajectories were distinguishable in all five corpus-language samples with a screening instrument (AUC 0.647–0.667) and four of five after sentence-level rescoring with the primary sentiment model.The effect survived contributor-level inference and seven controls for ending-related material. Shuffling sentence order eliminated the mean descent while preserving lexical content, localizing the effect to sequence. Matched first-person waking accounts, fiction, and encyclopedic prose also declined, showing that downward movement is not dream-specific. However, on the endpoint estimand, Dreamseer and DreamBank declined more strongly than waking narratives (all q < .001); after standardization by within-document sentence-valence dispersion, they also exceeded all three human comparators (9/9 contrasts, q ≤ .018), with approximately two- to five-fold greater descent. Separation was less consistent for whole-trajectory slope. The hypothesized failure of emotional resolution at the ending was unsupported: the difference was concentrated earlier, with dreams beginning near neutral and then declining.At population scale, Friday reports were lighter than Monday reports in English (β = +0.024, p = .008), but this did not replicate in Russian, was uncorrected, and partly reflected who reported. Nightmare-content variance increased before 12 downturns (Kendall’s τ = +0.236), surviving four of five surrogate tests but not a window-length block bootstrap; autocorrelation did not increase. We treat this as a prospective hypothesis, not evidence of critical slowing down. Low intrinsic dimension and a percolating semantic “continent” also appeared in matched non-dream prose, whereas non-narrative prose fell outside the connectivity range shared by all narrative corpora.Weekly affect and content showed no robust entrainment to market, media, search, attention, or cultural indicators, constraining detectable direct societal coupling at this temporal resolution. At COVID-19 onset, explicit pandemic vocabulary increased ninefold (+4.68 percentage points), exceeding all 44 placebo-in-time cutoffs (empirical p = .022), showing that the stream could register a major societal event.Together, these findings demonstrate collective structure without sustained interpersonal synchrony. Macroscopic organization emerged despite absent average-night convergence and a thin unexplained tail of unusually cohesive nights, while trajectory, calendar, variance, and event-related observables operated through partly independent channels.
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 |